Newbie - pt II - tables/computers
Alan Browne
The Swiss couple I met (and usually had a drink or three with almost
daily) insisted on the merits of their computers. The lady, one day,
took a full day out of diving (they were there for diving only over a
3.5 week period) as her computer told her to take a 31 hour surface
interval.
She had been making daily deep dives (first dive) to 100 - 130 feet
almost daily followed invariably by a shallower dive 30 - 60.
As I learned to use the tables and 'chain' successive dives together, I
could see no trend indicating that one would accumulate a large required
surface interval. At least not on the basis of two dives per day, the
first being to 130'.
So the question goes, are the computers too conservative? (Tables too
loose?). I know the computers also "give" as they integrate finely and
give "credit" for the fact that a 45 minute dive to 130 feet is not all
spent that deep, but it seems in integrating overall tissue N2 they are
too conservative.
The second question goes, the Swiss told me there are places in the
world that will not take you out diving unless you have a computer. Is
this so?
Thx.
--
gmail originated posts are filtered due to spam.
Greg Mossman
wrote:
> So the question goes, are the computers too conservative? (Tables too
> loose?). I know the computers also "give" as they integrate finely and
> give "credit" for the fact that a 45 minute dive to 130 feet is not all
> spent that deep, but it seems in integrating overall tissue N2 they are
> too conservative.
I've never heard of a computer that recommends any sort of interval;
rather, the computers limit NDL time or impose deco stops
appropriately based on the length of the surface interval (and all
have manuals that recommend one-hour minimum intervals just as the
agencies do). The only interval that my computers have ever
recommended is the pre-flight interval.
> The second question goes, the Swiss told me there are places in the
> world that will not take you out diving unless you have a computer. Is
> this so?
Possibly, but then those places are likely to rent computers for those
who don't have them.
Ecnerwal
Alan Browne <alan....@FreelunchVideotron.ca> wrote:
> So the question goes, are the computers too conservative? (Tables too
> loose?). I know the computers also "give" as they integrate finely and
> give "credit" for the fact that a 45 minute dive to 130 feet is not all
> spent that deep, but it seems in integrating overall tissue N2 they are
> too conservative.
There are conservative computers, and there are aggressive computers.
Buy one to suit your personal style. One reason to use a conservative
model is that people do get bent diving within the bounds of tables and
computers - this should have been mentioned in class.
But if you are an aggressive diver and buy a conservative computer, you
will probably just ignore it and go diving when it's locked you out for
a deco violation - I've certainly see people do that. As such, an
aggressive diver should choose an aggressive computer, so it's at least
of some use to them. But an aggressive diver is inherently more likely
to get bent, period.
The recreational tables are not really formulated with an eye to diving
every day for nearly a month. Many people choose to take a day off (or
limit it to a half-day of diving) in the middle of a mere week of diving.
Computers can also penalize you for the things you *actually* do, as
opposed to the nice clean plan you didn't actually follow - for
instance, if you ascend faster than you should on tables, the table
doesn't know that. If you ascend faster than you should with a computer,
it can slap a fudge factor on your surface interval to allow for that.
My conservative (Suunto) computer will penalize for ascent rate, lack of
safety stop, insufficient surface interval and several other things as
well as actual missed decompression stops. The latter would be per the
manual, as I've never run it into decompression - it and I are well
matched.
Screwing up threading to save a post:
>> I like the Apollo bio-fins (with the slit),
>> and they seem to have some decent actual test data supporting better
>> efficiency.
>I could probably generate better test data for a pair of strap on
>bricks. That's a cynical remark regarding manufacturer influenced test
>data.
That's "independent tests by other people" - the aforementioned Rodale's
for one. The methodology seemed pretty decent. They were specifically
trying to get past the vague claims of of manufacturers.
They've done it for several years: here's 2005
http://www.scubadiving.com/gear/2007/03/2005-fin-test
http://www.scubadiving.com/gear/2006/11/2005-fin-test-protocols
I don't actually own a pair, though my wife does. I have used hers when
I was surface snorkeling and she was sitting on the boat, and my
impression is that they are better than the paddle fins I use. Since I
can outswim her with the ones I use, and we almost invariably are each
other's buddies, there's no point in me getting any, at least until
these ones break.
--
Cats, coffee, chocolate...vices to live by
Greg Mossman
<MyNameForw...@ReplaceWithMyVices.Com.invalid> wrote:
> Computers can also penalize you for the things you *actually* do, as
> opposed to the nice clean plan you didn't actually follow - for
> instance, if you ascend faster than you should on tables, the table
> doesn't know that. If you ascend faster than you should with a computer,
> it can slap a fudge factor on your surface interval to allow for that.
> My conservative (Suunto) computer will penalize for ascent rate, lack of
> safety stop, insufficient surface interval and several other things as
> well as actual missed decompression stops. The latter would be per the
> manual, as I've never run it into decompression - it and I are well
> matched.
If you've never run a Suunto into deco, you must dive conservative!
But deco or not, I never argue with my Suunto. Perhaps that's what
Alan's Swiss lady friend did; maybe her 31-hour imposed surface
interval was because she screwed up. I hadn't considered that. I
even try to obey the optional deep-stop recommendations on my D9, and
would rather profane God than disobey a mandatory imposed deco stop.
Normally it's NDL all the way to the surface, but I've had it
occasionally impose a 1-minute mandatory "safety" stop on dives when
I'm ascending directly rather than taking my time exploring shallower
realms on the way up. I usually dive nitrox, so it's only made it
into unplanned deco a few times, but when I dove the Spiegel Grove
using optimal nitrox mixes (29% for a bounce to 140 on the first dive,
followed by 35% for a max of around 90'), the bastard stuck me with a
minute at 20' and 8 minutes at 10', right when there were 6 man-eating
huge barracudi at 15' on the mooring line. I turned my back to the
sinister fishies and did my time.
Hoges in WA
"Greg Mossman" <mos...@qnet.com> wrote in message
news:305baa58-5779-4c91...@g8g2000pri.googlegroups.com...
On Jan 29, 3:03 pm, Ecnerwal
<MyNameForw...@ReplaceWithMyVices.Com.invalid> wrote:
>[snipped]
If you've never run a Suunto into deco, you must dive conservative!
But deco or not, I never argue with my Suunto. Perhaps that's what
Alan's Swiss lady friend did; maybe her 31-hour imposed surface
interval was because she screwed up. I hadn't considered that. I
even try to obey the optional deep-stop recommendations on my D9, and
would rather profane God than disobey a mandatory imposed deco stop.
Normally it's NDL all the way to the surface, but I've had it
occasionally impose a 1-minute mandatory "safety" stop on dives when
I'm ascending directly rather than taking my time exploring shallower
realms on the way up. I usually dive nitrox, so it's only made it
into unplanned deco a few times, but when I dove the Spiegel Grove
using optimal nitrox mixes (29% for a bounce to 140 on the first dive,
followed by 35% for a max of around 90'), the bastard stuck me with a
minute at 20' and 8 minutes at 10', right when there were 6 man-eating
huge barracudi at 15' on the mooring line. I turned my back to the
sinister fishies and did my time.
===========
Greg
On a scale of 1-10 with 10 being ecstatic, how happy are you with your D9?
And, on a lawyer-joke note, do you wear it into court to show the judge just
what depths you will go to?
(just curious)
Seriously, though, I've had D9 after D9 on my eBay watchlist for about 2yrs
and am on the verge of hitting "Buy Now".
Hoges in WA
Greg Mossman
> Greg
> On a scale of 1-10 with 10 being ecstatic, how happy are you with your D9?
>
> And, on a lawyer-joke note, do you wear it into court to show the judge just
> what depths you will go to?
> (just curious)
Ha.
Even though it's more watch-sized than other wrist computers, it's
still sort of thick and geeky looking for a suave lawyer like myself
to be showing off in court.
> Seriously, though, I've had D9 after D9 on my eBay watchlist for about 2yrs
> and am on the verge of hitting "Buy Now".
Maybe a 9. I really like it, except for one annoying feature that's
probably just a defect in my particular computer. It's sometimes come
"un-paired" from the pressure sensor in the first stage right before
making a dive. Usually I've been able to get it re-paired and
properly displaying tank pressure on the wrist before descending
(sometimes having to turn off my air and bleed the reg, then turn the
air back on while holding the computer near the first stage sensor),
but there was that one time...
Now, as soon as I've checked my air and made sure that the pressure is
transmitting to my wrist, I keep the pairing "alive" by randomly
pressing buttons every 30 seconds or so until it's time to dive.
Also, the compass mode really sucks.
Other than those complaints, I do love it. It does everything I could
possibly want it to do, even tell time!
Hoges in WA
Ha.
========================================
Damn. There goes any excuse not to get one.
Do you know what the "5 zones" calibration thing means? I've asked Suunto
for more info on it as we plan to be off around the world from next year on,
beginning in Florida in about March '11.
I want to know if it travels through zones well or whether it is useless
outside its "birthplace" Haven't heard back yet.
Probably get one for my wife for her birthday in Feb then get one myself
later, assuming it travels well.
Hoges in WA
Alan Browne
> On Jan 29, 1:14 pm, Alan Browne<alan.bro...@FreelunchVideotron.ca>
> wrote:
>
>> So the question goes, are the computers too conservative? (Tables too
>> loose?). I know the computers also "give" as they integrate finely and
>> give "credit" for the fact that a 45 minute dive to 130 feet is not all
>> spent that deep, but it seems in integrating overall tissue N2 they are
>> too conservative.
>
> I've never heard of a computer that recommends any sort of interval;
> rather, the computers limit NDL time or impose deco stops
> appropriately based on the length of the surface interval (and all
> have manuals that recommend one-hour minimum intervals just as the
> agencies do). The only interval that my computers have ever
> recommended is the pre-flight interval.
Per the lady in question, her computer recommended the surface interval.
>
>> The second question goes, the Swiss told me there are places in the
>> world that will not take you out diving unless you have a computer. Is
>> this so?
>
> Possibly, but then those places are likely to rent computers for those
> who don't have them.
Of course. Must engage brain.
Alan Browne
Was there air hanging there or you had enough in your tank?
In Cancun I swam up to a pretty large brown barracuda while snorkeling.
He hung around for 15 seconds and then buggered off. I only got one
photo (with a "disposable" so not too hot).
Alan Browne
Is it possible to use such paired computer/pressure sensors with rental
gear, or is it part of a personal regulator set?
Is a needle magnetic compass better? I look forward to doing underwater
nav. (I used to teach flying and navigation was a favourite subject;
also did a little orienteering).
Dan Bracuk
<alan....@FreelunchVideotron.ca> wrote:
>The second question goes, the Swiss told me there are places in the
>world that will not take you out diving unless you have a computer. Is
>this so?
Probably. Once you improve your consumption you'll appreciate using a
computer.
Greg Mossman
> Damn. There goes any excuse not to get one.
>
> Do you know what the "5 zones" calibration thing means? I've asked Suunto
> for more info on it as we plan to be off around the world from next year on,
> beginning in Florida in about March '11.
See, now you're being more helpful to me than I was to you.
Scratching my befuddled head, I decided to look at the manual
regarding compass calibration - it says to recalibrate it often, and
especially after battery changes. Oops. No wonder I've been having
compass issues. I'll have to try calibrating it on my next trip.
The only thing I can figure out about zones is the info Suunto gives
on its website for its liquid-filled compasses. But shouldn't
calibration of the D9's digital compass eliminate that sort of
problem?
In any case, I've rarely bothered with the compass since I tend to not
use a compass much if I have visual references. I mainly need it to
find a reciprocal if I've been traveling across sand without
discernable depth changes indicating shore and need to return in the
direction I came from without getting completely lost and it's worked
fine for that in the past. I'll definitely calibrate it before I use
it again.
> I want to know if it travels through zones well or whether it is useless
> outside its "birthplace" Haven't heard back yet.
Again, AFAIK, that would only apply to liquid-filled compasses that
can't be re-calibrated. But since I don't use the compass feature
much, I can't say for sure. All I can tell you is that the rest of
the features travel just fine.
> Probably get one for my wife for her birthday in Feb then get one myself
> later, assuming it travels well.
Sure, give the wife the bad compass. It's not like you were ever
gonna trust a woman's sense of direction anyway :)
When we get lost, I simply ask Janna which way she would go, then we
go in the opposite direction. Who needs a compass for that?
Greg Mossman
> Again, AFAIK, that would only apply to liquid-filled compasses that
> can't be re-calibrated. But since I don't use the compass feature
> much, I can't say for sure. All I can tell you is that the rest of
> the features travel just fine.
And by "calibration", I really meant "declination". From the D9
manual: "You can compensate for the difference between true north and
magnetic north by adjusting the compass declination. The declination
can be found, for example, from
sea charts or topographic maps of the local area." and "NOTE When
traveling overseas, it is recommended that you recalibrate the compass
at the new location before using it."
So yes, I do believe it is designed to work in other locales if you're
willing to find sea charts or topographic maps and figure out the
declination. Hopefully someone at Wakatobi will know that sort of
thing for my next trip, but I still doubt I'll be using the compass.
The reason why I wouldn't use the compass for "real" navigation is
that you lose access to other crucial information (tank pressure, for
one). If I ever got back into lousy viz local diving and really
needed a compass, I'd use a real compass. (Also, I've heard it's a
battery hog in compass mode and I'd rather not replace batteries more
often than necessary.)
Greg Mossman
wrote:
> Is it possible to use such paired computer/pressure sensors with rental
> gear, or is it part of a personal regulator set?
You can use whatever you like with rental gear as long as the rental
shop doesn't see what you do to it as soon as it's outside their
shop. Simply remove the gauges and high-pressure hose, then screw in
the pressure sensor for a hoseless air-integrated computer. Voila.
But since the fancy hoseless air-integrated computer often costs more
than several regulators, you might want to buy your own regulator
first. Then you can mess with it all you want. I use a Seacure
mouthpiece, for instance, that I find far more comfortable on long
dives than the standard type. Other people have a long hose fetish
and try to outdo each other getting the longest hoses they can find
and wrapping them around themselves in creative and convoluted ways.
Whatever turns you on.
> Is a needle magnetic compass better? I look forward to doing underwater
> nav. (I used to teach flying and navigation was a favourite subject;
> also did a little orienteering).
Underwater navigation is probably closer to flying than orienteering
since currents don't affect one's ability to navigate on land. Also,
it's often hard to get a good sense of how far you've traveled on any
one "leg" of your navigation pattern since we perceive distance
differently, our finning speed can vary, and again, currents can mess
everything up. Pilots nowadays have onboard computers that can take
wind direction and wind speed and factor that into computing a heading
that can take you to your desired destination, but unfortunately even
the fancy D9 and its compass can't do anything like that. Any
compensation for currents is in your head, which makes underwater
navigation more of an art or skill than a mechanical process. When
you finally get it right and actually get right back to the mooring
line after an hour of exploring in different directions, you'll be
pleasantly amazed.
Greg Mossman
wrote:
> Was there air hanging there or you had enough in your tank?
Actually had plenty left in the tank since I had rented 120s (you can
rent whatever you want in Florida - not so easy to do in most other
parts of the world). Janna was on a 100 and our air consumption is
close enough normally that she becomes the limiting factor if she's
diving a smaller tank. I actually like the trim of the high-pressure
120 over the 100 since it's longer for my taller frame and that's what
I used to dive back when I dove locally, but when matched with a diver
who has less air, it becomes a handy safety factor. I don't believe
she had any issues lasting out the full 8 minutes but if she had been
running low, I would have had no problem sharing.
But since that extra bit of air isn't always available, it's
definitely not a good idea getting into unplanned deco until you know
your dive profiles and your dive computer well enough to sort of be
able to plan for the unplanned. When your air consumption improves,
you should have no problem lasting an extra 8 minutes at 10' as long
as you've been ascending in time to allow you back at the surface with
500psi remaining as all the dive ops stress.
> In Cancun I swam up to a pretty large brown barracuda while snorkeling.
> He hung around for 15 seconds and then buggered off. I only got one
> photo (with a "disposable" so not too hot).
Supposedly they don't bite unless you're wearing something flashy/
silvery. Still, as evil as they look lurking around with their big
sharp teeth, I don't trust them. It's only a matter of time until one
bites Janna (she's my guinea pig for any dive-related maladies that
might other strike me).
Actually, the only barracudi "bite" I've ever seen on a dive trip was
on a guy who went out fishing on his pre-flight post-dive day. He
caught a barracuda and when he lifted it up for a photo, he cut his
finger on the teeth. Only a truly evil fish could still be so
dangerous after it's dead. Me, I like happy fish like Napoleon Wrasse
that smile all the time and even let you pet them.
Alan Browne
> On Jan 30, 8:26 am, Greg Mossman<moss...@qnet.com> wrote:
>
>> Again, AFAIK, that would only apply to liquid-filled compasses that
>> can't be re-calibrated. But since I don't use the compass feature
>> much, I can't say for sure. All I can tell you is that the rest of
>> the features travel just fine.
>
> And by "calibration", I really meant "declination". From the D9
Could there also be calibration to offset the effect of changes to the
casing over time? (On aircraft compasses this is required every 6
months (IFR) or 12 months (VFR) - you set up on a magnetic aligned
compass rose (on an airport taxiway) and calibrate every 30' of heading
to within a degree or so - there are little iron bars that move in and
out very slightly to effect the change). (Similar to ship "boxing the
compass"). Not declination.
> manual: "You can compensate for the difference between true north and
> magnetic north by adjusting the compass declination. The declination
> can be found, for example, from
> sea charts or topographic maps of the local area." and "NOTE When
> traveling overseas, it is recommended that you recalibrate the compass
> at the new location before using it."
>
> So yes, I do believe it is designed to work in other locales if you're
> willing to find sea charts or topographic maps and figure out the
> declination. Hopefully someone at Wakatobi will know that sort of
> thing for my next trip, but I still doubt I'll be using the compass.
>
> The reason why I wouldn't use the compass for "real" navigation is
> that you lose access to other crucial information (tank pressure, for
> one). If I ever got back into lousy viz local diving and really
> needed a compass, I'd use a real compass. (Also, I've heard it's a
> battery hog in compass mode and I'd rather not replace batteries more
> often than necessary.)
Thanks for that last bit. I'll get a 'real' compass.
Alan Browne
> On Jan 30, 7:01 am, Alan Browne<alan.bro...@FreelunchVideotron.ca>
> wrote:
>
>> Is it possible to use such paired computer/pressure sensors with rental
>> gear, or is it part of a personal regulator set?
>
> You can use whatever you like with rental gear as long as the rental
> shop doesn't see what you do to it as soon as it's outside their
> shop. Simply remove the gauges and high-pressure hose, then screw in
> the pressure sensor for a hoseless air-integrated computer. Voila.
>
> But since the fancy hoseless air-integrated computer often costs more
> than several regulators, you might want to buy your own regulator
> first. Then you can mess with it all you want. I use a Seacure
> mouthpiece, for instance, that I find far more comfortable on long
> dives than the standard type. Other people have a long hose fetish
> and try to outdo each other getting the longest hoses they can find
> and wrapping them around themselves in creative and convoluted ways.
> Whatever turns you on.
Less is more. I found the supplied hose a little too short, but by
maybe 3 or 4 inches. The instructor had an extra long octo hose (which
was useful when he was my "air tanker" - I didn't have to look like I
was mating with him when stealing his air.)
>
>> Is a needle magnetic compass better? I look forward to doing underwater
>> nav. (I used to teach flying and navigation was a favourite subject;
>> also did a little orienteering).
>
> Underwater navigation is probably closer to flying than orienteering
> since currents don't affect one's ability to navigate on land. Also,
> it's often hard to get a good sense of how far you've traveled on any
> one "leg" of your navigation pattern since we perceive distance
> differently, our finning speed can vary, and again, currents can mess
> everything up. Pilots nowadays have onboard computers that can take
> wind direction and wind speed and factor that into computing a heading
> that can take you to your desired destination, but unfortunately even
That requires a TAS input to the computer, which light aircraft
typically don't have (I used to be a flight instructor - once upon a
time). Just as easy to use an old wheel computer (EB-6 for example),
compute the TAS from the IAS, temperature and ALT, mark that on the
wheel along HDG; compute the GS from landmark observation; offset the
heading from the track and the vector on the wheel to center/GS is the
wind direction and heading. Hell, I haven't done that exercise in over
20 years but its clear in my head.
> the fancy D9 and its compass can't do anything like that. Any
> compensation for currents is in your head, which makes underwater
> navigation more of an art or skill than a mechanical process. When
> you finally get it right and actually get right back to the mooring
> line after an hour of exploring in different directions, you'll be
> pleasantly amazed.
Oh, I get that. During all of the dives there was only one where I was
really disoriented. I usually had a fair sense of where the boat was
relative to me (direction, at least, not distance so well). Still, the
notion of figuring position more accurately is interesting. But not a
priority for now.
Dan Bracuk
Wanna buy mine? I can put it on eBay.
Greg Mossman
OK, now do it without IAS or an old wheel computer and see how clear
it is in your head. That's underwater navigation.
> Oh, I get that. During all of the dives there was only one where I was
> really disoriented. I usually had a fair sense of where the boat was
> relative to me (direction, at least, not distance so well). Still, the
> notion of figuring position more accurately is interesting. But not a
> priority for now.
Nope, only becomes a priority when you start planning and executing
your own dives. For now, you're a newbie, and newbies are better off
following more experienced divers until they get the hang of it. That
really goes for all task loading, whether it be underwater
photography, lobster hunting, or showing off fancy navigation skills.
Master the basics first, then you can add to your repetoire. Would
you want to be talking on the cell phone or texting while you were
still learning how to drive a manual transmission in traffic as a
teenager? Well today's teenagers probably do. Maybe I need a better
analogy.
Alan Browne
Not yet. Need to prioritize.
Alan Browne
> On Jan 30, 10:40 am, Alan Browne<alan.bro...@FreelunchVideotron.ca>
> Master the basics first, then you can add to your repetoire. Would
> you want to be talking on the cell phone or texting while you were
> still learning how to drive a manual transmission in traffic as a
> teenager? Well today's teenagers probably do. Maybe I need a better
> analogy.
I get ya. When my son got around to getting his driver's license I not
only forbade him using a cell phone with the engine running, but he
could have no more that one other passenger on board... (yes, manual).
Hoges in WA
==============================
This discussion has proven quite useful. I was wrongly assuming that "set"
for 5 differing locales would give me problems similar to the ones you find
in "zoned" Playstations and DVD players etc, where you need some sort of
magic code to open them up to other zones.
Now I realise that the zoned bit refers only to the compass and, like you, I
know where I'm going anyway, so the compass is the least of my wants.
They are much cheaper to buy ex-USA and I have seen the warning from Oz
sellers that 9s purchased elsewhere are not calibrated for local
conditions - this would appear to be posturing to dissuade Oz buyers from
stepping outside their local purchase area.
We plan to be on the East Coast of the USA next year anyway so if I have
warranty issues or battery replacement ones, I can get them fixed then.
2 x D9s coming up.
Hoges in WA
Greg Mossman
> They are much cheaper to buy ex-USA and I have seen the warning from Oz
> sellers that 9s purchased elsewhere are not calibrated for local
> conditions - this would appear to be posturing to dissuade Oz buyers from
> stepping outside their local purchase area.
>
> We plan to be on the East Coast of the USA next year anyway so if I have
> warranty issues or battery replacement ones, I can get them fixed then.
>
> 2 x D9s coming up.
I bought mine "grey market" from Leisure Pro. At first Suunto would
still service those, but then they turned over their U.S. service to
U.S. Divers/Aqualung and they refused to service unauthorized
purchases. So I paid $40 for a place in Colorado to do my last
battery change/maintenance check, not a big deal and it's only every
two years. For the hundreds I saved, well worth it.
The only other complaints people have are
1) Small numbers: tank pressure is displayed at the bottom right
corner and I supposed could be hard to read for far-sighted people,
but I don't have that problem yet and have never had an issue reading
the numbers. Depth is displayed in the center in big numbers.
There's no way Suunto could package all those features into a tiny
package without compromising on number size.
2) Ultra-conservatism: yes, it is a very conservative computer with
RGBM and imposed deep-stops, but it's not really that bad. I do most
of my diving on nitrox and the only time I ever had to do more than a
"safety stop" worth of deco was on the Spiegel Grove when we spent too
much time at depth on the first dive and had an inadequate surface
interval before the second. Otherwise, it's held up just fine on
liveaboards and Bonaire trips where I'll make 4 dives a day. Even
when I took a tech class and we used V-Planner to plan the dives, I
programmed my gas switch into the Suunto and it only imposed a couple
more minutes of deco than V-Planner before cleared me to ascend.
Since I'm not exactly a teetotaler on my dive holidays, and not
exactly in top triathalon shape, I welcome the extra bit of
conservatism knowing that it's keeping me safer.
The best tribute I can give it is that if it were to crap out tomorrow
and I had to buy a new computer before my next trip, I'd buy another
D9.
Douglas W. "Popeye" Frederick
"Alan Browne" <alan....@FreelunchVideotron.ca> wrote in message
news:CM-dnZLkFehe0v7W...@giganews.com...
> So the question goes, are the computers too conservative? (Tables too
> loose?). I know the computers also "give" as they integrate finely and
> give "credit" for the fact that a 45 minute dive to 130 feet is not all
> spent that deep, but it seems in integrating overall tissue N2 they are
> too conservative.
Computers dive your dive with you.
Tables -guess- at what your dive is.
And they're computer generated anyway.
With the exception of some extended-range extreme dives with remarkably
square profiles, there's no comparison.
Computers are essential for multi-day, multi-level diving.
> The second question goes, the Swiss told me there are places in the world
> that will not take you out diving unless you have a computer. Is this so?
At the very least, there are many places that will require you to dive a
very restricted profile without a computer.
--
--
Popeye
"If one does as God does enough times, one
will become as God is." -Dr. Hannibal Lector.
www.finalprotectivefire.com
http://picasaweb.google.com/Popeye8762
Uwe Hercksen
Alan Browne schrieb:
> The Swiss couple I met (and usually had a drink or three with almost
> daily) insisted on the merits of their computers. The lady, one day,
> took a full day out of diving (they were there for diving only over a
> 3.5 week period) as her computer told her to take a 31 hour surface
> interval.
Hello,
may be she ascended to fast for the computer or she didn't wait until
the end of a deco stop, or she didn't stay precisely enough at the depth
of the deco stop, therefore the comnputer insisted on a 31 hout surface
interval.
Bye
-hh
> Ecnerwal wrote:
> > Computers can also penalize you for the things you *actually* do, as
> > opposed to the nice clean plan you didn't actually follow - for
> > instance, if you ascend faster than you should on tables, the table
> > doesn't know that. If you ascend faster than you should with a computer,
> > it can slap a fudge factor on your surface interval to allow for that.
> > My conservative (Suunto) computer will penalize for ascent rate, lack of
> > safety stop, insufficient surface interval and several other things as
> > well as actual missed decompression stops. The latter would be per the
> > manual, as I've never run it into decompression - it and I are well
> > matched.
>
> If you've never run a Suunto into deco, you must dive conservative!
> But deco or not, I never argue with my Suunto. Perhaps that's what
> Alan's Swiss lady friend did; maybe her 31-hour imposed surface
> interval was because she screwed up. I hadn't considered that.
I've put my Suunto Vyper into Deco .. I've never had it insist on any
sort of huge surface intervals, which does make this sound like the
Swiss Lady likely had some sort of violation, so the computer locked
her topside.
Of course, a magnitude of 31 hours also kind of sounds like it could
have alternatively been a "Time to Fly" time requirement; if this was
the cause of her skipping her last day of holiday, this could be
another possibility.
> I even try to obey the optional deep-stop recommendations on my D9, and
> would rather profane God than disobey a mandatory imposed deco stop.
Given how conservative the Suunto is even at its most liberal
settings, I'd generally be more concerned about losing a day of diving
for it locking up, than the DCS risk from not fully completing its
deco schedule.
BTW, if you do put a Suunto into Deco, do be aware that it is
surprisingly fussy about your hang depth: you really need to get up
to the top of the glass ceiling in order to clear the stop in anything
even remotely close to the time that it says it will take. IIRC, my
first experience was something like an 8-10 minute obligation, which I
did at my usual 15-17fsw safety stop depth, but which after ~15
minutes, hadn't budged more than a few minutes...so I came up to
~11fsw and it took around another 10 minutes to clear the remaining 7
minutes or so. All told, I had nearly a half hour hang at <20fsw
before it was finally satisfied, and that was from a profile that
probably was within the ancient USN Table's no-stop limit of "25 min @
100fsw" square profile...so how much DCS risk was there, really?
> ... the bastard stuck me with a
> minute at 20' and 8 minutes at 10', right when there were 6 man-eating
> huge barracudi at 15' on the mooring line. I turned my back to the
> sinister fishies and did my time.
They were what...all of 3ft long? :-)
-hh
Alan Browne
I don't know the details (their English was difficult to understand).
However they were both DM's, they both insisted on following the "rules"
for safe diving (and were critical of the less than safety-first
attitude of the instructor/DM's in the Carib... She liked to dive deep,
often. So the likelihood that she saturated her system rapidly and the
likelihood that she made a mistake on deco was higher than normal...
they were there for 3.5 weeks - it's got to build up.
Alan Browne
No, it was mid stride. They programmed a 2 day out before flying to dry
out their wetsuits...
Greg Mossman
> > I even try to obey the optional deep-stop recommendations on my D9, and
> > would rather profane God than disobey a mandatory imposed deco stop.
>
> Given how conservative the Suunto is even at its most liberal
> settings, I'd generally be more concerned about losing a day of diving
> for it locking up, than the DCS risk from not fully completing its
> deco schedule.
Exactly. That's why we must obey God-Suunto, even if it tells us that
the only way to avoid deco is to sacrifice a child. It's a lot
cheaper to buy spare children for sacrifice in Indonesia then it is in
Florida, though that might be alleviated by all the recent child-
smuggling from Haiti.
> BTW, if you do put a Suunto into Deco, do be aware that it is
> surprisingly fussy about your hang depth: you really need to get up
> to the top of the glass ceiling in order to clear the stop in anything
> even remotely close to the time that it says it will take. IIRC, my
> first experience was something like an 8-10 minute obligation, which I
> did at my usual 15-17fsw safety stop depth, but which after ~15
> minutes, hadn't budged more than a few minutes...so I came up to
> ~11fsw and it took around another 10 minutes to clear the remaining 7
> minutes or so. All told, I had nearly a half hour hang at <20fsw
> before it was finally satisfied, and that was from a profile that
> probably was within the ancient USN Table's no-stop limit of "25 min @
> 100fsw" square profile...so how much DCS risk was there, really?
I don't recall having any similar experiences, which hopefully means
they fixed that before making my D9. On the other hand, it would be
nice to have a way to fix the last deco stop at 15' instead of 10'
which is a lot more realistic in rough ocean conditions (maybe there
is, I should RTFM).
> > ... the bastard stuck me with a
> > minute at 20' and 8 minutes at 10', right when there were 6 man-eating
> > huge barracudi at 15' on the mooring line. I turned my back to the
> > sinister fishies and did my time.
>
> They were what...all of 3ft long? :-)
Yeah, whatever. I was still coming out of my narc from going deeper,
and either way 3' looks like 4' underwater. If they were happy big
fish like groupers or remoras, fine, but this was obviously a
conglomeration of 4' evildoers meant on keeping me from my date with
the surface. Fortunately I had Janna with me and angled myself so she
was in the firing line, just in case.
Greg Mossman
wrote:
> > Of course, a magnitude of 31 hours also kind of sounds like it could
> > have alternatively been a "Time to Fly" time requirement; if this was
> > the cause of her skipping her last day of holiday, this could be
> > another possibility.
>
> No, it was mid stride. They programmed a 2 day out before flying to dry
> out their wetsuits...
See, that's just plain weird. However, Swiss are known to be
extremely conservative. Since most computers can be programmed for
extra-conservatism, even Suuntos, it's possible she had hers
programmed to ensure she had extremely low residual nitrogen.
Nitrophobic!
Hoges in WA
====================
The reason for her conservatism is obvious.
She's Swiss.
There are airliners that don't fly as high as her house.
hoges in WA
-hh
> > Alan Browne <alan.bro...@FreelunchVideotron.ca> wrote:
> > > -hh wrote:
> > >> Of course, a magnitude of 31 hours also kind of sounds like it could
> > >> have alternatively been a "Time to Fly" time requirement; if this was
> > >> the cause of her skipping her last day of holiday, this could be
> > >> another possibility.
>
> > > No, it was mid stride. They programmed a 2 day out before flying to dry
> > > out their wetsuits...
>
> > See, that's just plain weird.
It does sound a bit odd, but perhaps we are reading a bit too much
into language translation - for a Swiss, French, German & Italian are
their official languages, so English is probably in 3rd or 4th, with
the country's 4th language of Romanish being less common overall.
Being that it was a midweek break, I recall that there are "take a day
off" recommendations from DAN, etc, so I think that this could be that
they were simply electing to take a mid-trip break day, but what got
lost in translation was the explanation of "who" (man vs. computer)
was calling for it.
>> However, Swiss are known to be
>> extremely conservative. Since most computers can be programmed for
>> extra-conservatism, even Suuntos, it's possible she had hers
>> programmed to ensure she had extremely low residual nitrogen.
>> Nitrophobic!
>
> ====================
> The reason for her conservatism is obvious.
> She's Swiss.
> There are airliners that don't fly as high as her house.
> hoges in WA
The Swiss may come off as conservative & reserved in some things, but
there's some real surprises when you really start to look. For
example, if they were so paranoid about personal safety, they wouldn't
have had explosives in place wired to blow tunnel in the country up
through the 1990s (& later). Similarly, lets not forget that it was
the Swiss who did some of the earliest diver-test trials with trying
to figure out DCS ... and I believed that I mentioned here awhile back
that I had the pleasure of meeting one of those original military
divers a few years ago...one of the ones who got pretzeled, IIRC, due
to a post-dive increase in altitude.
-hh
Greg Mossman
> It does sound a bit odd, but perhaps we are reading a bit too much
> into language translation - for a Swiss, French, German & Italian are
> their official languages, so English is probably in 3rd or 4th, with
> the country's 4th language of Romanish being less common overall.
>
> Being that it was a midweek break, I recall that there are "take a day
> off" recommendations from DAN, etc, so I think that this could be that
> they were simply electing to take a mid-trip break day, but what got
> lost in translation was the explanation of "who" (man vs. computer)
> was calling for it.
Maybe, but that begs the question of whether or not this is a
desirable practice, i.e. does it make a difference in safety to take a
day break over 3.5 weeks of making two dives a day. My feeling is
that it probably is a good thing to break up an intensive dive
schedule of four or five dives a day like you might do on a typical
liveaboard or at a dive-intensive resort or locale like Cocoview
(Roatan) or Bonaire, but doing two recreational-depth dives a day in
the morning followed by 20 or so hours of offgassing before the next
dive day can probably be continued far longer than 3.5 weeks without
imposing any undue health risks. Thoughts?
> The Swiss may come off as conservative & reserved in some things, but
> there's some real surprises when you really start to look. For
> example, if they were so paranoid about personal safety, they wouldn't
> have had explosives in place wired to blow tunnel in the country up
> through the 1990s (& later). Similarly, lets not forget that it was
> the Swiss who did some of the earliest diver-test trials with trying
> to figure out DCS ... and I believed that I mentioned here awhile back
> that I had the pleasure of meeting one of those original military
> divers a few years ago...one of the ones who got pretzeled, IIRC, due
> to a post-dive increase in altitude.
And don't forget that William Tell fellow who would shoot apples off
people's heads for fun.
Alan Browne
> "Hoges in WA"<tzhogan...@bigpond.net.au> wrote:
>> "Greg Mossman"<moss...@qnet.com> wrote in message
>>> Alan Browne<alan.bro...@FreelunchVideotron.ca> wrote:
>>>> -hh wrote:
>>>>> Of course, a magnitude of 31 hours also kind of sounds like it could
>>>>> have alternatively been a "Time to Fly" time requirement; if this was
>>>>> the cause of her skipping her last day of holiday, this could be
>>>>> another possibility.
>>
>>>> No, it was mid stride. They programmed a 2 day out before flying to dry
>>>> out their wetsuits...
>>
>>> See, that's just plain weird.
>
> It does sound a bit odd, but perhaps we are reading a bit too much
> their official languages, so English is probably in 3rd or 4th, with
> the country's 4th language of Romanish being less common overall.
>
> Being that it was a midweek break, I recall that there are "take a day
> off" recommendations from DAN, etc, so I think that this could be that
> they were simply electing to take a mid-trip break day, but what got
> lost in translation was the explanation of "who" (man vs. computer)
> was calling for it.
She clearly indicated it was the computer that set the 31 hour surface
interval.
This is what began my discussions with them on the validity of computers
- and led to his inane (to me) notion that because the computer
integrates depth-time so well, that its computation of nitrogen load in
the body is correct v. the slop in the system and the slop in tables and
the many unknow-ables...
-hh
> -hh <recscuba_goo...@huntzinger.com> wrote:
>
> > Being that it was a midweek break, I recall that there are "take a day
> > off" recommendations from DAN, etc, so I think that this could be that
> > they were simply electing to take a mid-trip break day, but what got
> > lost in translation was the explanation of "who" (man vs. computer)
> > was calling for it.
>
> Maybe, but that begs the question of whether or not this is a
> desirable practice, i.e. does it make a difference in safety to take a
> day break over 3.5 weeks of making two dives a day.
I'd be inclined to say that my Suunto seems to think so: even the
typical 2-tank AM diveboat schedule has gotten it to the point where
its saying that Day "N" is Dives #5 and #6, since it didn't reset back
to #1 and #2, since with the same start time each morning, there
wasn't a full 24 hours between the first dive of the day and the end
of the second dive on the prior day.
> My feeling is
> that it probably is a good thing to break up an intensive dive
> schedule of four or five dives a day like you might do on a typical
> liveaboard or at a dive-intensive resort or locale like Cocoview
> (Roatan) or Bonaire, but doing two recreational-depth dives a day in
> the morning followed by 20 or so hours of offgassing before the next
> dive day can probably be continued far longer than 3.5 weeks without
> imposing any undue health risks. Thoughts?
In general, I don't really believe that there should be all that much
risk from 2 dives/day ad infinitum, but particularly since I had a
friend get a career-ending DCS-II hit on just such a regimen (IIRC,
around 20-30 days in), so I do have to believe that it would seem to
contain some unknown factor that somehow comes into play on such long
regimens. This is despite how it should seem that spending 90% of the
time (20+ hours) out of the water each day should logically make this
a moot issue.
In short, I think this is a "we don't know enough" issue, in part
because the profiles ... weeks of repetition ... are generally
uncommon, which gives us less insight of the risk to work with. My
personal hunch is that its not really a "really long compartment" in
the classical sense, but that all dives do some sort of discrete
'damage', and while this isn't a factor for "short term" dive series,
it can become one on a loooooong series.
For example, hypothetically consider a situation where our body
couldn't make red blood cells in our bone marrow while we're under X
pressure/depth. To lose a few hours worth of production once in
awhile ...or even a few days in a row...isn't generally a problem for
us, but if we were to dive every day...even for only 2 dives (2
hours)...the accumulation of this shortage over several weeks could
potentially cause a body to become anemic.
-hh
Alan Browne
> For example, hypothetically consider a situation where our body
> couldn't make red blood cells in our bone marrow while we're under X
> pressure/depth. To lose a few hours worth of production once in
> awhile ...or even a few days in a row...isn't generally a problem for
> us, but if we were to dive every day...even for only 2 dives (2
> hours)...the accumulation of this shortage over several weeks could
> potentially cause a body to become anemic.
The plain fact here is that without physiological measurements of what
is happening in the body over representative dive cycles ( 2 weeks
worth, a month, more) what is occurring is as much guess work as
anything else.
Research demands measurement before, during and after of the "what"
before "why" and what to do can follow.
This means implanting various sensors in a number of human bodies at a
number of body sites, including non-diving controls, and recording that
data at a useful frequency and then analyzing the data to see what's
happening, what are the variances, what are the short, medium and long
term changes and so on.
Greg Mossman
wrote:
> She clearly indicated it was the computer that set the 31 hour surface
> interval.
>
> This is what began my discussions with them on the validity of computers
> - and led to his inane (to me) notion that because the computer
> integrates depth-time so well, that its computation of nitrogen load in
> the body is correct v. the slop in the system and the slop in tables and
> the many unknow-ables...
Statistically it is more correct. All of the "unknowables" have been
factored into the equations used in the computers to come up with
profiles that keep 99%+ of us safe yet allowing far more bottom time
than tables that take the deepest part of the dive as the depth for
the entire time. The sheer number of unbent divers on computers are
testimony to their efficacy. And they look cool.
Greg Mossman
> Greg Mossman <moss...@qnet.com> wrote:
> > -hh <recscuba_goo...@huntzinger.com> wrote:
>
> > > Being that it was a midweek break, I recall that there are "take a day
> > > off" recommendations from DAN, etc, so I think that this could be that
> > > they were simply electing to take a mid-trip break day, but what got
> > > lost in translation was the explanation of "who" (man vs. computer)
> > > was calling for it.
>
> > Maybe, but that begs the question of whether or not this is a
> > desirable practice, i.e. does it make a difference in safety to take a
> > day break over 3.5 weeks of making two dives a day.
>
> I'd be inclined to say that my Suunto seems to think so: even the
> typical 2-tank AM diveboat schedule has gotten it to the point where
> its saying that Day "N" is Dives #5 and #6, since it didn't reset back
> to #1 and #2, since with the same start time each morning, there
> wasn't a full 24 hours between the first dive of the day and the end
> of the second dive on the prior day.
Just semantics possibly. Even if the time to fully desaturate is
computed as less than 24 hrs, the computer will still sequentially
number the next day's dive in the same series because a different
algorithm tells it that the dives are part of the same dive trip.
I.e., just because the next dives are numbered 5 and 6 doesn't mean
the decompression algorithm hasn't necessarily reset itself. Yes, the
deco part of the computer is probably still tracking the dives after
24 hrs, but how much is it really penalizing the diver for
"repetitive" diving with such a long interval in between?
> > My feeling is
> > that it probably is a good thing to break up an intensive dive
> > schedule of four or five dives a day like you might do on a typical
> > liveaboard or at a dive-intensive resort or locale like Cocoview
> > (Roatan) or Bonaire, but doing two recreational-depth dives a day in
> > the morning followed by 20 or so hours of offgassing before the next
> > dive day can probably be continued far longer than 3.5 weeks without
> > imposing any undue health risks. Thoughts?
>
> In general, I don't really believe that there should be all that much
> risk from 2 dives/day ad infinitum, but particularly since I had a
> friend get a career-ending DCS-II hit on just such a regimen (IIRC,
> around 20-30 days in), so I do have to believe that it would seem to
> contain some unknown factor that somehow comes into play on such long
> regimens. This is despite how it should seem that spending 90% of the
> time (20+ hours) out of the water each day should logically make this
> a moot issue.
> In short, I think this is a "we don't know enough" issue, in part
> because the profiles ... weeks of repetition ... are generally
> uncommon, which gives us less insight of the risk to work with. My
> personal hunch is that its not really a "really long compartment" in
> the classical sense, but that all dives do some sort of discrete
> 'damage', and while this isn't a factor for "short term" dive series,
> it can become one on a loooooong series.
Or your anecdotal "friend" was an off-the-charts exception to the rule
that we all know happens occasionally. Sure, most vacations aren't
that long, but I can't believe there haven't been enough Navy studies,
DAN studies, etc. that longer-term effects couldn't be extrapolated
effectively into a computer model.
> For example, hypothetically consider a situation where our body
> couldn't make red blood cells in our bone marrow while we're under X
> pressure/depth. To lose a few hours worth of production once in
> awhile ...or even a few days in a row...isn't generally a problem for
> us, but if we were to dive every day...even for only 2 dives (2
> hours)...the accumulation of this shortage over several weeks could
> potentially cause a body to become anemic.
But there have been enough hyperbaric studies on humans and other
mammals that we would know if there are any major such bodily
processes that are affected by diving. No need for hypotheticals when
we have willing Navy "volunteers" :)
Now real world experiments would have us get the Navy sailors drunk
every night, maybe make them smoke cigarettes between each dive and
eat lots of fatty fried foods, and refrain from any sort of exercise
in between dives that might make them more approximate to certain dive
vacationers. When the Navy starts doing those sort of experiments,
I'll volunteer!
-hh
That's an unknown-to-us, because Suunto doesn't document/publish their
full algorithm in open literature. However, what I have observed is
that I can have a couple of days of 2-tank AM dives and then the next
day, instead of it being #1, #2 again, it starts with #3, #4, #5,
#6, ... until I take a full break day off.
Given this change in behavior of the machine, along with perceived
shorter no-stop times, my conclusion is that my bottom times are being
penalized within some aspect of their algorithm.
Could be that too, although this was a member of staff, and had been
doing the job for years...the resort was short on personnel, so they
weren't getting their usual break day(s), hence the very long
continuous cycle of daily diving.
> > For example, hypothetically consider a situation where our body
> > couldn't make red blood cells in our bone marrow while we're under X
> > pressure/depth. To lose a few hours worth of production once in
> > awhile ...or even a few days in a row...isn't generally a problem for
> > us, but if we were to dive every day...even for only 2 dives (2
> > hours)...the accumulation of this shortage over several weeks could
> > potentially cause a body to become anemic.
>
> But there have been enough hyperbaric studies on humans and other
> mammals that we would know if there are any major such bodily
> processes that are affected by diving. No need for hypotheticals when
> we have willing Navy "volunteers" :)
My point is merely that the human biological machine is a very complex
one that we still don't even fully know how all of its chemical
processes work on the surface, even before we muck them up with
hyperbaric exposure. It could very easily be some enzyme that we
don't even know exists yet, for the simple reason that we've not known
to look for it.
> Now real world experiments would have us get the Navy sailors drunk
> every night, maybe make them smoke cigarettes between each dive and
> eat lots of fatty fried foods, and refrain from any sort of exercise
> in between dives that might make them more approximate to certain dive
> vacationers. When the Navy starts doing those sort of experiments,
> I'll volunteer!
That's a young man's sport .. although in a similar vein, I can now
give you detailed directions to an establishment in Brussels that has
500 different kinds of Tequila available. Not that we tried it, but
their most expensive was EU 90 per shot.
-hh
Greg Mossman
> That's a young man's sport .. although in a similar vein, I can now
> give you detailed directions to an establishment in Brussels that has
> 500 different kinds of Tequila available. Not that we tried it, but
> their most expensive was EU 90 per shot.
It seems a bit perverse to me to travel all the way to Belgium for
expensive tequila when I can drive a few hours south and cross the
border to the country where all the stuff is made.
On the other hand, you can supposedly get real absinthe in Bangkok and
I just happen to be spending a night there in May on the way back from
Wakatobi. I'd welcome any advice on where to find the green elixir.
-hh
> -hh <recscuba_goo...@huntzinger.com> wrote:
>
> > That's a young man's sport .. although in a similar vein, I can now
> > give you detailed directions to an establishment in Brussels that has
> > 500 different kinds of Tequila available. Not that we tried it, but
> > their most expensive was EU 90 per shot.
>
> It seems a bit perverse to me to travel all the way to Belgium for
> expensive tequila when I can drive a few hours south and cross the
> border to the country where all the stuff is made.
And you've never been known to do _anything_ perverse? :-)
> On the other hand, you can supposedly get real absinthe in Bangkok and
> I just happen to be spending a night there in May on the way back from
> Wakatobi. I'd welcome any advice on where to find the green elixir.
From the above tequila bar, exit back to the street, turn left, go
~50ft (uphill) and turn right into the Absinthe bar; logo is a racier
looking green-haired version of "Tinkerbell". Not sure how many
different varieties of Absinthe they have, as their website is
currently messed up, but (reading Google caches) it looks like their
menu is ~5 pages at over 60 per page, so roughly 300 or so.
Put you down for a "Absinthe Tunel C A N N A B I S" (80°) ?
-hh
Alan Browne
> haired version of "Tinkerbell".
?
http://images.fanpop.com/images/image_uploads/Absinthe-Wallpaper-absinthe-446334_1024_768.jpg
-hh
wrote:
> On 10-02-03 20:24 , -hh wrote:
>
> > haired version of "Tinkerbell".
>
> ?
>
A nice image, but not the one from the establishment in question.
I'm going to give them the chance to reboot their website before the
reveal.
-hh
Alan Browne
A little research on the matter reveals that the French refer to
Absinthe as "La Fée Verte" (The Green Fairy), so there is a lot of
artwork incorporating such.
http://upload.wikimedia.org/wikipedia/commons/7/75/Albert_Maignan_-_La_muse_verte.jpg
http://upload.wikimedia.org/wikipedia/commons/b/bd/Oliva.jpg
http://firesoul.files.wordpress.com/2009/02/absinthe.jpg
Now I'm fascinated ...
Greg Mossman
> And you've never been known to do _anything_ perverse? :-)
>
> > On the other hand, you can supposedly get real absinthe in Bangkok and
> > I just happen to be spending a night there in May on the way back from
> > Wakatobi. I'd welcome any advice on where to find the green elixir.
>
> From the above tequila bar, exit back to the street, turn left, go
> ~50ft (uphill) and turn right into the Absinthe bar; logo is a racier
> looking green-haired version of "Tinkerbell". Not sure how many
> different varieties of Absinthe they have, as their website is
> currently messed up, but (reading Google caches) it looks like their
> menu is ~5 pages at over 60 per page, so roughly 300 or so.
>
> Put you down for a "Absinthe Tunel C A N N A B I S" (80°) ?
Apparently not perverse enough, or I'd keep up with this stuff. I
thought it was still illegal just about everywhere. But, according to
Wikipedia, not only "Belgium, as part of an effort to simplify its
laws, removed its absinthe law on 1 January 2005, citing (as did the
Dutch judge) European food regulations as sufficient to render the law
unnecessary (and indeed, in conflict with the spirit of the Single
European Market)" but also: "On March 5, 2007, the French Lucid brand
became the first genuine absinthe to receive a COLA (Certificate of
Label Approval) for legal importation into the United States since
1912,[39][40] following independent efforts by representatives from
Lucid and Kübler to topple the long-standing U.S. ban.[41] In December
2007, St. George Absinthe Verte, produced by St. George Spirits of
Alameda, California, became the first brand of American-made absinthe
to be legally produced in the United States since the enactment of the
ban.[42][43] Since that time, other micro-distilleries have started
making small batches of high-quality absinthe in the U.S."
I could swear that absinthe cocktails here were still made using
Pernod as a mediocre substitute. Obviously I must pay more attention
the next time I'm at an upscale bar.
-hh
>
> Now I'm fascinated ...
Well, their website is still broken, but here's their homepage:
<http://www.floris-bar.be/home/?lang=en>
-hh
Dillon Pyron
>On 10-01-29 17:48 , Greg Mossman wrote:
>> On Jan 29, 1:14 pm, Alan Browne<alan.bro...@FreelunchVideotron.ca>
>> wrote:
>>
>>> So the question goes, are the computers too conservative? (Tables too
>>> loose?). I know the computers also "give" as they integrate finely and
>>> give "credit" for the fact that a 45 minute dive to 130 feet is not all
>>> spent that deep, but it seems in integrating overall tissue N2 they are
>>> too conservative.
>>
>> I've never heard of a computer that recommends any sort of interval;
>> rather, the computers limit NDL time or impose deco stops
>> appropriately based on the length of the surface interval (and all
>> have manuals that recommend one-hour minimum intervals just as the
>> agencies do). The only interval that my computers have ever
>> recommended is the pre-flight interval.
>
>Per the lady in question, her computer recommended the surface interval.
I'm interested in the brand. How does it know what you're next
profile is going to be?
Now I have seen computer computer programs, but they let you simulate
dives. Which assumes a perfect replication of the anticipated dive
and perfect recall of the prior dive(s). They're fun to play with,
but I'd never put my life in their hands.
>
>>
>>> The second question goes, the Swiss told me there are places in the
>>> world that will not take you out diving unless you have a computer. Is
>>> this so?
>>
>> Possibly, but then those places are likely to rent computers for those
>> who don't have them.
>
>Of course. Must engage brain.
--
- dillon I am not invalid
I love my country, It's my government I fear.
Hey, turnabout's fair play.
Dillon Pyron
<Popey...@gmail.com>:
>
>"Alan Browne" <alan....@FreelunchVideotron.ca> wrote in message
>news:CM-dnZLkFehe0v7W...@giganews.com...
>
>> So the question goes, are the computers too conservative? (Tables too
>> loose?). I know the computers also "give" as they integrate finely and
>> give "credit" for the fact that a 45 minute dive to 130 feet is not all
>> spent that deep, but it seems in integrating overall tissue N2 they are
>> too conservative.
>
> Computers dive your dive with you.
>
> Tables -guess- at what your dive is.
Tables are great for planing.
"No plan survives first encounter"
>
> And they're computer generated anyway.
>
> With the exception of some extended-range extreme dives with remarkably
>square profiles, there's no comparison.
>
> Computers are essential for multi-day, multi-level diving.
>
>> The second question goes, the Swiss told me there are places in the world
>> that will not take you out diving unless you have a computer. Is this so?
>
> At the very least, there are many places that will require you to dive a
>very restricted profile without a computer.
>
>--
--
- dillon I am not invalid
JRE
<snip>
> Now I have seen computer computer programs, but they let you simulate
> dives. Which assumes a perfect replication of the anticipated dive
> and perfect recall of the prior dive(s). They're fun to play with,
> but I'd never put my life in their hands.
It's not that big a deal.
I bring a laptop on the boat. My dive computers (I dive with two) both
upload to the laptop, which then displays the complete dive profile.
Then I can adjust the first dive data and the second dive plan if need
be to account for variations on the first dive. This can be important
since I don't own computers that understand either trimix or deco gas
changes (and at about $1K each I might never buy them, as mine function
fine in bottom timer mode which is all I really need and I have other
uses for $2K). But it's rarely necessary on deep dives as those
profiles are nearly square most of the time.
Also, the software can and does generate variations on the intended
plan. +/- depth or time, and lost deco gas plans, are trivially
generated and easy enough to bring along on the dive if I want to have
them with me. In practice I carry the lost gas plans and simply
remember the deeper/longer plan variations.
Last, when I'm on air or nitrox, I can just fall back to the computers
if the dive goes significantly off-plan. The computers won't know about
accelerated deco, so I'll have less tissue loading when I surface later
than planned, but things could be a lot worse.
--
John Eells
Greg Mossman
> Dillon Pyron wrote:
>
> <snip>
>
> > Now I have seen computer computer programs, but they let you simulate
> > dives. Which assumes a perfect replication of the anticipated dive
> > and perfect recall of the prior dive(s). They're fun to play with,
> > but I'd never put my life in their hands.
>
> It's not that big a deal.
>
> I bring a laptop on the boat. My dive computers (I dive with two) both
That's a big deal on plenty of dive boats I've been on. Anything big
with an interior cabin, like a liveaboard, sure, but taking a laptop
on a small dive boat would severely limit that laptop's life
expectancy (of course with smartphones nowadays, you could
theoretically download to something small enough to fit inside a
ziplock baggie for protection, assuming you can make the connection to
your dive computers.)
JRE
> That's a big deal on plenty of dive boats I've been on. Anything big
> with an interior cabin, like a liveaboard, sure, but taking a laptop
> on a small dive boat would severely limit that laptop's life
> expectancy (of course with smartphones nowadays, you could
> theoretically download to something small enough to fit inside a
> ziplock baggie for protection, assuming you can make the connection to
> your dive computers.)
I have been doing this for a while now and I haven't had one damaged in
the slightest; even on 6-packs and smaller boats there is always space
to stash a laptop in an out-of-the-way corner. And many or most of the
boats out of NY, NJ, and MA have considerably more space than a 6-pack.
The laptop lives inside a large ziploc bag placed inside a padded
backpack.
The dive gear on the deck is another story. Tanks are heavy and regs
are fragile.
The laptop is also nice to have when someone gets bent and either the
diver or I has the download cable for the computer, because we can see
what happened right there on the boat.
I have been looking for a PDA that will run the software I like to use
but unfortunately the smartphones seem to have killed the PDA market and
they seem quite scarce. I know other divers who use PDAs this way but
have yet to find one for sale that I can use.
The new netbooks coming out are getting cheaper and smaller every day,
though, and cost about what good PDAs used to. I might buy one of those
at some point. V-planner doesn't need a fast CPU or much memory, and
the netbooks come with USB ports and could probably fit in, say, a
hard-sided pistol case or in a Pelican case smaller than those I
routinely see used for underwater cameras.
--
John Eells
Joerg Hahn
Alan Browne wrote:
> 3.5 week period) as her computer told her to take a 31 hour surface
> interval.
>
Probably she mixed up saturation time and surface interval.
31h saturation time seems possible.
Computer brands common in Eu show SOS but then do not countdown time. AFAIR.
> She had been making daily deep dives (first dive) to 100 - 130 feet
> almost daily followed invariably by a shallower dive 30 - 60.
Which is not "deep" and as a result, 31h saturation time is supposable.
> As I learned to use the tables and 'chain' successive dives together, I
> could see no trend indicating that one would accumulate a large required
> surface interval. At least not on the basis of two dives per day, the
> first being to 130'.
Right. Recommendation here in EU is minimum 2h SI, better 3h.
Also, no DC is recommending Surface Intervals AFAIK.
Also the SOS-Mode basically means, you did something, the DC can`t
calculate, isn`t set for or it is simply malfunctioning.
You should always consider, what you did. Or did`t do.
> So the question goes, are the computers too conservative?
well, some are, some not. Modern DC seem to calculate everything
according marketing. But if you investigate, they have the same old
functioning algorithms with added time punishment for little mishaps.
Marketing calls it "New Algorithms" and "more conservative".
Same whine in new bottles.
(Tables too loose?).
you might say so. They are not made for "multi level". If you use them
there, you spent too much time making deko stops. But they are nice for
"fall back" in case the DC is failing and to get a general overview,
what`s going on. On the other hand DCs do not protect you 100% against
every accident. Even when you do, what they tell you.
I know the computers also "give" as they integrate finely and
> give "credit" for the fact that a 45 minute dive to 130 feet is
hoho, wait a minute. it might not be deep, but 130ft which is 40meter?
and that for 45mins Bottom Time is way past even my table.
A dive with a total length of 45min an a max depth 40m has usually a
bottom time of about max. 8-12 min, which is not such a big deal in warm
water, high viz.
> spent that deep, but it seems in integrating overall tissue N2 they are
> too conservative.
Remember, the time you spent in a specific depth is more relevant than
the depth on its own. In other words, its more the dive time which leads
to saturation, especially on multilevel dives.
Depth is overestimated.
> The second question goes, the Swiss told me there are places in the
> world that will not take you out diving unless you have a computer. Is
> this so?
Yes. Sometimes only because they want to rent the DC with a fee.
Sometimes the operators don`t want to mess with guests who invest so
little in their hobby.
Joerg
--
Die neuen Knips-Fotos aus dem Urlaub:
http://www.notabstieg.de/maledives-4-2009/index.html
http://www.grabmalkultur.de
Joerg Hahn
Greg Mossman wrote:
> Now, as soon as I've checked my air and made sure that the pressure is
> transmitting to my wrist, I keep the pairing "alive" by randomly
> pressing buttons every 30 seconds or so until it's time to dive.
(pairing procedure)
That`s what Suuntos do. This was my biggest issue by choosing an Uwatec.
They use fix matching. Which can be reprogrammed as much as you like it.
Makes much more sense on a 2,3, bottle environment.
And I need reading glasses for a watch like computer.
> Also, the compass mode really sucks.
They all do.
Alan Browne
> Hi Alan,
>
> Alan Browne wrote:
>> I know the computers also "give" as they integrate finely and
>> give "credit" for the fact that a 45 minute dive to 130 feet is
>
> hoho, wait a minute. it might not be deep, but 130ft which is 40meter?
> and that for 45mins Bottom Time is way past even my table.
>
> A dive with a total length of 45min an a max depth 40m has usually a
> bottom time of about max. 8-12 min, which is not such a big deal in warm
> water, high viz.
I meant total time with a bottom time of 5 - 10 minutes implied.
>
>> spent that deep, but it seems in integrating overall tissue N2 they
>> are too conservative.
>
> Remember, the time you spent in a specific depth is more relevant than
> the depth on its own. In other words, its more the dive time which leads
> to saturation, especially on multilevel dives.
> Depth is overestimated.
>
>> The second question goes, the Swiss told me there are places in the
>> world that will not take you out diving unless you have a computer. Is
>> this so?
>
> Yes. Sometimes only because they want to rent the DC with a fee.
> Sometimes the operators don`t want to mess with guests who invest so
> little in their hobby.
Seems like a poor business plan.
Greg Mossman
> I have been doing this for a while now and I haven't had one damaged in
> the slightest; even on 6-packs and smaller boats there is always space
> to stash a laptop in an out-of-the-way corner. And many or most of the
> boats out of NY, NJ, and MA have considerably more space than a 6-pack.
> The laptop lives inside a large ziploc bag placed inside a padded
> backpack.
CA dive boats are the same, usually 60+ footers with bunks and galley,
plenty of space indoors to fiddle with a dry laptop. But I was
thinking more on the lines of the warm-water six-pacs that barely have
any cover, spray water everywhere when they're in motion, and often
get exposed to tropical showers. On those such boats, we keep
everything in a dry bag. Just trying to keep the little nitrox
analyzer from getting wet can be problematic enough, keeping a laptop
dry near impossible.
> The laptop is also nice to have when someone gets bent and either the
> diver or I has the download cable for the computer, because we can see
> what happened right there on the boat.
Which means dive computers should be more functional as stand-alones.
My tiny Suunto, for example, displays a beautiful graphical profile of
my entire dive on its itty-bitty face. No need to download anything.
> I have been looking for a PDA that will run the software I like to use
> but unfortunately the smartphones seem to have killed the PDA market and
> they seem quite scarce. I know other divers who use PDAs this way but
> have yet to find one for sale that I can use.
So make a dive computer that has all the functions you'd want on the
PDA, even including V-Planner. If technology can compress full PC
functionality into a little cell phone, surely it could squeeze V-
Planner and such into a dive computer, especially the larger models.
I'd buy one, as long as you can make it tell time too like my Suunto.
Greg Mossman
wrote:
> > Yes. Sometimes only because they want to rent the DC with a fee.
> > Sometimes the operators don`t want to mess with guests who invest so
> > little in their hobby.
>
> Seems like a poor business plan.
Not if it works. Some experienced divers find a computer requirement
an asset because it means that the dive op is used to more experienced
divers and allowing more independence from the DM's profile.
Alan Browne
Any business that forces the rental of equipment, to me, is using a poor
business plan. There are no legally mandated requirements for such
equipment.
The only equipment I see that has a mandated requirement are the bottles
(pressure ratings, date of manufacture, date of pressure test, etc.)
I would hazard a guess that in those countries where dive-ops are
"mandating" computers that the country does not have or does not
actually enforce bottle regulations.
I'm not fighting this (despite my tone) BTW. If this becomes a regular
enough activity that I start to equip, then the purchase of a computer
is likely. (But getting a needle compass comes first).
I'm just skeptical of ad hoc requirements v. "best practices" as defined
by the diver.
John Hanson
<recscub...@huntzinger.com> wrote in rec.scuba:
>
>I've put my Suunto Vyper into Deco .. I've never had it insist on any
>sort of huge surface intervals, which does make this sound like the
>Swiss Lady likely had some sort of violation, so the computer locked
>her topside.
>
I have an Aladdin Prime that I used for all of my tech training (I now
have a VR3 fully unlocked) that I used as a back up for my bottom
timer. The Prime doesn't have gauge mode but I did discover that if
you bend the hell out of it (like I did in Advanced Trimix), it
operates in gauge mode.
I left mine set at 21% (lowest it will go) even though I was using
15/50 and did a 220 FFW followed by a 210 FFW dive after a 3 1/2 hour
SI. It told me I had over 2 hours of deco at 10 FFW when I surfaced.
I was quite pleased when I noticed on the second dive that it told me
the depth and time. :)
Joerg Hahn
-hh wrote:
> From the above tequila bar, exit back to the street, turn left, go
> ~50ft (uphill) and turn right into the Absinthe bar; logo is a racier
> looking green-haired version of "Tinkerbell". Not sure how many
> different varieties of Absinthe they have, as their website is
> currently messed up, but (reading Google caches) it looks like their
> menu is ~5 pages at over 60 per page, so roughly 300 or so.
>
> Put you down for a "Absinthe Tunel C A N N A B I S" (80�) ?
The next morning you might miss an ear ;-)
I would stick to beer in Brussels. They are more famous for that than
foreign drinks.
joerg
-hh
> -hh wrote:
> > From the above tequila bar, exit back to the street, turn left, go
> > ~50ft (uphill) and turn right into the Absinthe bar; logo is a racier
> > looking green-haired version of "Tinkerbell". Not sure how many
> > different varieties of Absinthe they have, as their website is
> > currently messed up, but (reading Google caches) it looks like their
> > menu is ~5 pages at over 60 per page, so roughly 300 or so.
>
> > Put you down for a "Absinthe Tunel C A N N A B I S" (80°) ?
>
> The next morning you might miss an ear ;-)
Oh No Van Gogh!
> I would stick to beer in Brussels. They are more famous for that than
> foreign drinks.
>
> http://www.biertempel.be/
Agreed; I've walked past that place, but haven't stopped in, since
their beer is really for home consumption. Here's the path to the
street I was referring to...which in addition to the tequila and
absinthe also includes the establishment that started it all, with its
2000+ beer varieties (more than even Greg can manage in a week)...its
just a two minute walk (or for Greg, a six minute stumble? :-) away:
-hh
Joerg Hahn
> their beer is really for home consumption. Here's the path to the
> street I was referring to...which in addition to the tequila and
> absinthe also includes the establishment that started it all, with its
> 2000+ beer varieties (more than even Greg can manage in a week)...its
> just a two minute walk (or for Greg, a six minute stumble? :-) away:
From where I live 250 km away, so a good 2hour trip.
lg
Joerg
Greg Mossman
> -hh wrote:
> > their beer is really for home consumption. Here's the path to the
> > street I was referring to...which in addition to the tequila and
> > absinthe also includes the establishment that started it all, with its
> > 2000+ beer varieties (more than even Greg can manage in a week)...its
> > just a two minute walk (or for Greg, a six minute stumble? :-) away:
>
> From where I live 250 km away, so a good 2hour trip.
Braggart.
I can get to Catalina Island in 2 hours, with giant kelp, bat rays,
sea lions, giant sea bass, and lobsters galore. Unfortunately the
water is too damn cold, more like the temperature of something you
should drink rather than dive in. No wonder all you landlocked
Germans, Dutch, Belgians, etc. spend so much time making and drinking
cold beer instead of diving. It's a worthy substitute.
Dillon Pyron
>Greg Mossman wrote:
>
>> That's a big deal on plenty of dive boats I've been on. Anything big
>> with an interior cabin, like a liveaboard, sure, but taking a laptop
>> on a small dive boat would severely limit that laptop's life
>> expectancy (of course with smartphones nowadays, you could
>> theoretically download to something small enough to fit inside a
>> ziplock baggie for protection, assuming you can make the connection to
>> your dive computers.)
>
>I have been doing this for a while now and I haven't had one damaged in
>the slightest
Kiss of Death. As they say in the old gangster movies "you'll be
sleeping with the fish tonight"
>; even on 6-packs and smaller boats there is always space
>to stash a laptop in an out-of-the-way corner. And many or most of the
>boats out of NY, NJ, and MA have considerably more space than a 6-pack.
> The laptop lives inside a large ziploc bag placed inside a padded
>backpack.
Just as long as you don't need to plug it in. Even more so on the big
boats. The power is crap, at best. Many of them have square wave
output or sawtooth. Sine waves are for sissies. And spikes? All the
time.
>
>The dive gear on the deck is another story. Tanks are heavy and regs
>are fragile.
>
>The laptop is also nice to have when someone gets bent and either the
>diver or I has the download cable for the computer, because we can see
>what happened right there on the boat.
This also assumes a computer that you can get download data from. Or
that's compatible with the software you're running for your computer.
>
>I have been looking for a PDA that will run the software I like to use
>but unfortunately the smartphones seem to have killed the PDA market and
>they seem quite scarce. I know other divers who use PDAs this way but
>have yet to find one for sale that I can use.
>
>The new netbooks coming out are getting cheaper and smaller every day,
>though, and cost about what good PDAs used to. I might buy one of those
>at some point. V-planner doesn't need a fast CPU or much memory, and
>the netbooks come with USB ports and could probably fit in, say, a
>hard-sided pistol case or in a Pelican case smaller than those I
>routinely see used for underwater cameras.
Netbooks are still way over priced and underperforming. You do get
better battery life, but that only counts if you need the sucker to be
up for long periods of time. And as soon as you start talking about
stuffing one in a Pelican, you've tossed away weight savings. They
aren't getting any smaller. A ten inch screen is just about as small
as you can reasonably expect to go and still be useful. And the
keyboards are just about it. My iPhone's keyboard is monsterous
compared to a Blackberry, and it's still pretty small unless I put the
thing in landscape.
Dillon Pyron
>Hi Greg,
>
>Greg Mossman wrote:
>
>> Now, as soon as I've checked my air and made sure that the pressure is
>> transmitting to my wrist, I keep the pairing "alive" by randomly
>> pressing buttons every 30 seconds or so until it's time to dive.
>
>(pairing procedure)
>
>That`s what Suuntos do. This was my biggest issue by choosing an Uwatec.
>They use fix matching. Which can be reprogrammed as much as you like it.
>Makes much more sense on a 2,3, bottle environment.
>
>And I need reading glasses for a watch like computer.
My newest mask has bifocals. Suddenly, I can read my computer without
having to hod it out about a foot further than I can reach.
>
>> Also, the compass mode really sucks.
>
>They all do.
>
>Joerg
--
- dillon I am not invalid