raw files are HUGE
Sameer
I tried winzip and winrar but they cant compress them much. Is there
anything else which works?
Ken Lucke
Sameer <sameer...@gmail.com> wrote:
> I tried winzip and winrar but they cant compress them much. Is there
> anything else which works?
>
Raw files come out of the camera pretty close to as efficient as they
are going to get. You're not going to be very sucessful in attempting
to compress them further, regardless of the program or compression
scheme that you try.
You think a raw file is huge? Try converting it to .tif and see where
it goes. My 8-9 megabyte raws go to 57.8 MB when converted to 16 bit
.tif files.
Besides, what's the problem? Storage has never been cheaper - I just
picked up [yet another] Maxtor 300 GB Firewire/USB drive from Costco
for $149, including cables... that's 50 cents a gig. That makes 3
250GB, 1 400GB, and 2 300 GB drives attached to my system.
<memory lane trip>
I remember the first commercially available hard drive [1981, the Apple
ProFile, available for the Apple /// computer, subsequently (1983) with
a controller card that allowed its use on the Apple //[e|c]], it
contained a single Seagate ST-506 HD with a whoppin' 5 MEGAbytes of
storage space (and no one at the time thought you could *ever* fill it
up) and close to $5000 new (IIRC) - almost $1000 per MEGAbyte. These
things were almost as big as a tower case is now, and weighed about as
much as a tank. Later, the massive 10 megabyte model was released.
</memory lane>
--
You need only reflect that one of the best ways to get yourself a
reputation as a dangerous citizen these days is to go about repeating
the very phrases which our founding fathers used in the struggle for
independence.
-- Charles A. Beard
timeOday
> Besides, what's the problem? Storage has never been cheaper - I just
> picked up [yet another] Maxtor 300 GB Firewire/USB drive from Costco
> for $149, including cables... that's 50 cents a gig. That makes 3
> 250GB, 1 400GB, and 2 300 GB drives attached to my system.
>
I have surely appreciated the crazy explosion in flash memory capacity,
but hard drives are not keeping pace. I was just looking for a drive
today and was disappointed that hard drive prices haven't fallen more
since I bought my last drive a few years ago.
For instance:
<http://www.pcworld.com/article/id,77543-page,1/article.html>
"Less than a year ago, a $300, 80GB desktop drive was considered huge;
today you can find a 160GB drive for the same price."
That was in January of 02'! According to this, between January of '01
and January of '02 capacity doubled to 160 GB while the price remained
constant. If that trend had continued, you could now buy a 5 terabyte
drive for $300. Instead it's $300 for 750GB.
Consulting pricewatch from 4 years ago, I came up with the following
annual growth rates:
Flash: 138%
Hard drive: 32%
RAM: 19%
For comparison, Moore stated his "Law" at 100% per year in 1965,
and at 41% (doubling every other year) in 1975. It is often quoted at
doubling every 18 months, which would be 59% per year.
Yeah, I'm spoiled. But compared to last century, this one isn't doing
so hot. (Except for Flash).
For the interested, here's the data I used:
Look at pricewatch on the internet archive from 4 years ago:
<http://web.archive.org/web/20030128022327/http://www.pricewatch.com/>
A 120GB drive was $117, and the maximum available size was 250GB.
Now, 4 years later, that same $120 will buy you a 400 GB drive and the
max available size is 750GB.
<http://www.pricewatch.com/hard_drives/>
So in 4 years, price is basically constant while capacity has gone up by
a little more than a factor of 3.
Meanwhile, using the same sources, 4 years ago a 256 MB usb flash drive
was $75. Today for $79 you get an 8 GB flash. That's a factor of 32!
In 2002, 1GB of PC133 RAM would set you back $144.
In 2007, for the same price you can get 1 GB ddr2-1066 1gb or 2GB
DDR2-400. The cheapest 1GB module now is PC100 for $60.
So in 4 years, RAM has only doubled in capacity for the same price.
ray
>
> I tried winzip and winrar but they cant compress them much. Is there
> anything else which works?
That is because, like executable files, there is much entropy there. The
data is inherently not very compressible. I note on my 5mp camera that
jpegs run 1-2mb; raws are around 8-9mb; and tiffs are 15mb - I guess it's
all relative - I can still pack a lot of pictures on a $25 2gb memory card.
The Grape Smasher Ltd.
doesn't compress the DNG raw files, but does compress the PEF raw files. I
shoot DNG, when I get home I use the Adobe DNG converter to compress the DNG
files in to DNG files. This takes their size from about 16MB to about half
that at around 8MB. Try using Adobe DNG converter, it is free and can
downloaded off the Adobe site and it may give you smaller files.
TGC Ltd.
"Sameer" <sameer...@gmail.com> wrote in message
news:1172974599....@i80g2000cwc.googlegroups.com...
Rod Speed
That isnt as true with the best after rebate prices.
CJT
> Ken Lucke wrote:
>
>> Besides, what's the problem? Storage has never been cheaper - I just
>> picked up [yet another] Maxtor 300 GB Firewire/USB drive from Costco
>> for $149, including cables... that's 50 cents a gig. That makes 3
>> 250GB, 1 400GB, and 2 300 GB drives attached to my system.
>>
>
> I have surely appreciated the crazy explosion in flash memory capacity,
> but hard drives are not keeping pace. I was just looking for a drive
> today and was disappointed that hard drive prices haven't fallen more
> since I bought my last drive a few years ago.
>
There has been a lot of consolidation in the hard drive industry,
resulting in an oligopoly. Without competitive pressures, prices
will not decline at the same pace.
--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form che...@prodigy.net.
Rod Speed
> timeOday wrote:
>
>> Ken Lucke wrote:
>>
>>> Besides, what's the problem? Storage has never been cheaper - I
>>> just picked up [yet another] Maxtor 300 GB Firewire/USB drive from
>>> Costco for $149, including cables... that's 50 cents a gig. That
>>> makes 3 250GB, 1 400GB, and 2 300 GB drives attached to my system.
>>>
>>
>> I have surely appreciated the crazy explosion in flash memory
>> capacity, but hard drives are not keeping pace. I was just looking
>> for a drive today and was disappointed that hard drive prices
>> haven't fallen more since I bought my last drive a few years ago.
>>
>
> There has been a lot of consolidation in the hard drive industry,
> resulting in an oligopoly. Without competitive pressures, prices
> will not decline at the same pace.
Have fun explaining how come you dont get the same
effect with flash ram which has the same problem.
Matt Ion
> timeOday wrote:
>
>> Ken Lucke wrote:
>>
>>> Besides, what's the problem? Storage has never been cheaper - I just
>>> picked up [yet another] Maxtor 300 GB Firewire/USB drive from Costco
>>> for $149, including cables... that's 50 cents a gig. That makes 3
>>> 250GB, 1 400GB, and 2 300 GB drives attached to my system.
>>>
>>
>> I have surely appreciated the crazy explosion in flash memory
>> capacity, but hard drives are not keeping pace. I was just looking
>> for a drive today and was disappointed that hard drive prices haven't
>> fallen more since I bought my last drive a few years ago.
>>
>
> There has been a lot of consolidation in the hard drive industry,
> resulting in an oligopoly. Without competitive pressures, prices
> will not decline at the same pace.
Kinda gotta consider where you shop as well.
Right now, a retail-boxed internal 300GB/16MB Maxtor SATA drive (exact model
unspecified) would cost me CDN$236(!!!) at Staples... meanwhile my regular
retailer sells a 500GB/16MB SATA-II packed only in an antistatic bag, for
CDN$169 (they don't even list a 300, but a 250 is $85-$95). That's a lotta
extra cash for a cardboard box and "installation instructions".
The Grape Smasher Ltd.
poor warranties with OEM (plastic bag only) items. If you buy a retail CPU
and a retail motherboard Intel gives you the warranty through them for 3
years on each. If you go OEM they don't warrant anything and leave it up to
the place you bought it. For example an OEM CPU from TigerDirect has a 1
year warranty and it is through them.
So make sure that the extra you pay isn't for warranty. Though honestly the
price difference still doesn't warrant that. If a drive or CPU or
Motherboard is going to fail it would surely do it within a year. Just make
sure that you do get a warranty and if it is handled by the place you buy
from that you can count on them being in business for at least the length of
warranty.
TGC Ltd.
"Matt Ion" <soun...@gmail.com> wrote in message
news:uNIGh.1221431$5R2.461484@pd7urf3no...
Sameer
My files must be compressed already or winzip would have got more than
2% (:
I don't like DNG, the convertor doesn't let me convert back to
original format. I read a little bit about it and it seems not many
people use it.
On Mar 5, 12:18 am, "The Grape Smasher Ltd." <nos...@nospam.com>
wrote:
> Some cameras don't compress their raw files. For example the Pentax K10D
> doesn't compress the DNG raw files, but does compress the PEF raw files. I
> shoot DNG, when I get home I use the Adobe DNG converter to compress the DNG
> files in to DNG files. This takes their size from about 16MB to about half
> that at around 8MB. Try using Adobe DNG converter, it is free and can
> downloaded off the Adobe site and it may give you smaller files.
>
> TGC Ltd.
>
> "Sameer" <sameerxah...@gmail.com> wrote in message
The Grape Smasher Ltd.
the DNG at any time. You of course are back to large files.
As for Winzip and RAR neither one of them was designed for image or audio or
video data. There were designed for documents and programs. So the fact that
they give you next to nothing isn't a surprise and doesn't mean your images
can't be compressed a lot. You just have to use something designed for that
kind of data.
TGC Ltd.
"Sameer" <sameer...@gmail.com> wrote in message
news:1173120163.4...@30g2000cwc.googlegroups.com...
Bill Funk
<timeOda...@theknack.net> wrote:
>For comparison, Moore stated his "Law" at 100% per year in 1965,
>and at 41% (doubling every other year) in 1975. It is often quoted at
>doubling every 18 months, which would be 59% per year.
Moore didn't state a "law."
He made an observation.
And the observation was concerning chips, and had nothing to do with
hard drives.
Trying to compare the density of transistors on chips and aerial
density of hardd rives is comparing apples and potatos.
--
John Edwards was warned by Democrats
in Nevada Thursday that his support
for a bill to ban betting on college
sports will cost him the state. You
have to love Nevada. It's the only
place where a personal injury lawyer
has the moral high ground.
AZ Nomad
>On Sat, 03 Mar 2007 22:44:15 -0700, timeOday
><timeOda...@theknack.net> wrote:
>>For comparison, Moore stated his "Law" at 100% per year in 1965,
>>and at 41% (doubling every other year) in 1975. It is often quoted at
>>doubling every 18 months, which would be 59% per year.
>Moore didn't state a "law."
>He made an observation.
>And the observation was concerning chips, and had nothing to do with
>hard drives.
His observation has been valid for hard drives.
Arno Wagner
> On Sat, 03 Mar 2007 22:44:15 -0700, timeOday
> <timeOda...@theknack.net> wrote:
>>For comparison, Moore stated his "Law" at 100% per year in 1965,
>>and at 41% (doubling every other year) in 1975. It is often quoted at
>>doubling every 18 months, which would be 59% per year.
> Moore didn't state a "law."
> He made an observation.
> And the observation was concerning chips, and had nothing to do with
> hard drives.
Indeed. The ''law'' was made out of his observations by the press, I
beliveve.
> Trying to compare the density of transistors on chips and aerial
> density of hardd rives is comparing apples and potatos.
More like apples and fish, really.
Arno
Arno Wagner
To some degree for capacities. Not at all for interface speeds.
And they are not his observations for HDDs, since he did not
observe HDDs at all.
Arno
AZ Nomad
Know of many consumer hard drives that did 80MB/s in 1995? In 1997, a $500
10Krpm scsi-3 drive was only good for 3-4MB/s. In 1985, consumer PC hard
drivess were good for maybe 500KB/s. Right now I'm getting 80MB/s on a $140
500GB drive. Sure sounds like a geometric progression to me.
Pretty much, drive speeds have gone up in step with drive capacities.
You get greater capacity either with more platters or a higher data density.
Both translate to greater throughput given the same rotational speed.
Alexander Grigoriev
1994. This was on a IDE card connected to VESA bus.
"AZ Nomad" <azno...@PremoveOBthisOX.COM> wrote in message
news:slrneupa7o.r...@ip70-176-155-130.ph.ph.cox.net...
Bob Willard
> Pretty much, drive speeds have gone up in step with drive capacities.
> You get greater capacity either with more platters or a higher data density.
> Both translate to greater throughput given the same rotational speed.
Uh, adding platters does nothing for STR. More throughput, but all of
the data about speed in this thread has been about STR.
{Long long ago, in a galazy near near to us, more platters meant higher
STRs for a special class of expensive HDs that did parallel reads from
multiple heads. But everything made today reads (and writes) one head
at a time. If you want RAID0, the economics of HDs make it cheaper to
deploy multiple HDs than multiple heads on the same HD, at least for now.}
HD STR has never maintained a 60% CAGR over any period of a decade or so
for mainstream HDs AFAIK.
--
Cheers, Bob
Bill Funk
Lead balls dropped in air acellerate at a certain rate.
Do you, therefore, expect feathers dropped in air to acellerate at the
same rate?
But you *observed* the lead balls.
Moore's observation had/has nothing to do with hard drives.
--
Hillary Clinton went to a civil
rights ceremony in Selma Sunday
and spoke to a local black Baptist
Church congregation. She mentioned
her husband at the top of her
speech. Whenever you face a tough
crowd you have to open with your
best joke.
Arno Wagner
> On Mon, 05 Mar 2007 21:39:35 GMT, AZ Nomad
> <azno...@PremoveOBthisOX.COM> wrote:
>>On Mon, 05 Mar 2007 14:24:44 -0700, Bill Funk <Big...@there.com> wrote:
>>
>>
>>>On Sat, 03 Mar 2007 22:44:15 -0700, timeOday
>>><timeOda...@theknack.net> wrote:
>>
>>>>For comparison, Moore stated his "Law" at 100% per year in 1965,
>>>>and at 41% (doubling every other year) in 1975. It is often quoted at
>>>>doubling every 18 months, which would be 59% per year.
>>
>>>Moore didn't state a "law."
>>>He made an observation.
>>>And the observation was concerning chips, and had nothing to do with
>>>hard drives.
>>His observation has been valid for hard drives.
> Lead balls dropped in air acellerate at a certain rate.
> Do you, therefore, expect feathers dropped in air to acellerate at the
> same rate?
> But you *observed* the lead balls.
> Moore's observation had/has nothing to do with hard drives.
Good analogy.
Arno
AZ Nomad
>On Mon, 05 Mar 2007 21:39:35 GMT, AZ Nomad
><azno...@PremoveOBthisOX.COM> wrote:
>>On Mon, 05 Mar 2007 14:24:44 -0700, Bill Funk <Big...@there.com> wrote:
>>
>>
>>>On Sat, 03 Mar 2007 22:44:15 -0700, timeOday
>>><timeOda...@theknack.net> wrote:
>>
>>>>For comparison, Moore stated his "Law" at 100% per year in 1965,
>>>>and at 41% (doubling every other year) in 1975. It is often quoted at
>>>>doubling every 18 months, which would be 59% per year.
>>
>>>Moore didn't state a "law."
>>>He made an observation.
>>>And the observation was concerning chips, and had nothing to do with
>>>hard drives.
>>His observation has been valid for hard drives.
>Lead balls dropped in air acellerate at a certain rate.
>Do you, therefore, expect feathers dropped in air to acellerate at the
>same rate?
Huh?
>But you *observed* the lead balls.
>Moore's observation had/has nothing to do with hard drives.
non sequitur
Bill Funk
<azno...@PremoveOBthisOX.COM> wrote:
>On Tue, 06 Mar 2007 09:07:18 -0700, Bill Funk <Big...@there.com> wrote:
>
>
>>On Mon, 05 Mar 2007 21:39:35 GMT, AZ Nomad
>><azno...@PremoveOBthisOX.COM> wrote:
>
>>>On Mon, 05 Mar 2007 14:24:44 -0700, Bill Funk <Big...@there.com> wrote:
>>>
>>>
>>>>On Sat, 03 Mar 2007 22:44:15 -0700, timeOday
>>>><timeOda...@theknack.net> wrote:
>>>
>>>>>For comparison, Moore stated his "Law" at 100% per year in 1965,
>>>>>and at 41% (doubling every other year) in 1975. It is often quoted at
>>>>>doubling every 18 months, which would be 59% per year.
>>>
>>>>Moore didn't state a "law."
>>>>He made an observation.
>>>>And the observation was concerning chips, and had nothing to do with
>>>>hard drives.
>>>His observation has been valid for hard drives.
>
>>Lead balls dropped in air acellerate at a certain rate.
>>Do you, therefore, expect feathers dropped in air to acellerate at the
>>same rate?
>Huh?
>
>
>>But you *observed* the lead balls.
>>Moore's observation had/has nothing to do with hard drives.
>non sequitur
Not at all.
Moore's observation was about transistor counts on chips.
That's what he observed.
He made no observation about hard drives.
Chips=lead ball.
Hard drive=feathers.
Get it?
John Turco
>
> Ken Lucke wrote:
>
> > Besides, what's the problem? Storage has never been cheaper - I just
> > picked up [yet another] Maxtor 300 GB Firewire/USB drive from Costco
> > for $149, including cables... that's 50 cents a gig. That makes 3
> > 250GB, 1 400GB, and 2 300 GB drives attached to my system.
> >
>
> I have surely appreciated the crazy explosion in flash memory capacity,
> but hard drives are not keeping pace. I was just looking for a drive
> today and was disappointed that hard drive prices haven't fallen more
> since I bought my last drive a few years ago.
<edited, for brevity>
Hello, timeOday:
Hard disks have been around far longer, than flash memory. Hence, it's
unrealistic to expect the same kinds of rapid price/performance gains,
from such mature technology.
Cordially,
John Turco <jt...@concentric.net>
Roger
>timeOday wrote:
>>
>> Ken Lucke wrote:
>>
>> > Besides, what's the problem? Storage has never been cheaper - I just
>> > picked up [yet another] Maxtor 300 GB Firewire/USB drive from Costco
>> > for $149, including cables... that's 50 cents a gig. That makes 3
However using USB or firewire greately limits the speed. Now you can
install an external SATA 3 that will run as fast as the internal
drives.
>> > 250GB, 1 400GB, and 2 300 GB drives attached to my system.
I paid $10 USD less than that each for 4 500 Gig SATA 3 drives.
$139 X 4 = $556 for 2 Terabytes.
>> >
>>
>> I have surely appreciated the crazy explosion in flash memory capacity,
Flash memory hasn't come close to being able to match hard drives for
capacity. Yes, I can purchase a 1 Gig CF for about $20 to $30
compared to the $70 at discount I paid for them when first available.
Stores were selling them for $129 at the time.
But at any rate, when you compare the changes in HDs from the many
thousands of dollars for a 10 Meg Winchester drive of the 80's to the
1 Terabyte USB external drives for $400 give or take about $50 those
HDs certainly have kept pace with drive capacity for a reasonable
price about trippeling in the last year.
>> but hard drives are not keeping pace. I was just looking for a drive
>> today and was disappointed that hard drive prices haven't fallen more
>> since I bought my last drive a few years ago.
You've been going to the wrong stores. A few years ago HDs were
expensive and running in the 120 Gig range. I have one left that is
that small. I have over 6 terabytes...make that 7 between 5
computers.
Those 5 500 Gig SATA 3 drives with 16 meg caches cost about 1.5 times
the price of the 120 Gig drive I mentioned. You can now purchase 80 to
120 Gig drives for around $50 pt $60 with a bit of shopping. Actually
Best Buy had 250s for $89 a while back.
I just looked at New Egg and they have a 250 Gig SATA 3 WD (8 meg
cache)for $70, a 320 Seagate SATA 3 for $90 and a 500 Gig SATA 3 WD
for $139. The last two have 16 Meg caches.
BTW they have a 1 Terabyte external with 32 Meg Cache set up for both
USB2 and Firewire and fan cooled for $379 after rebate. ($9 shipping)
>
><edited, for brevity>
>
>Hello, timeOday:
>
>Hard disks have been around far longer, than flash memory. Hence, it's
>unrealistic to expect the same kinds of rapid price/performance gains,
>from such mature technology.
What we are seeing is still a rapid increase in capacity and prices
*still* coming down. One Terabyte external (with fan) for about the
same price as a 400 Gig just 6 months ago.
>
>
>Cordially,
> John Turco <jt...@concentric.net>
Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com
chrisv
>Hard disks have been around far longer, than flash memory. Hence, it's
>unrealistic to expect the same kinds of rapid price/performance gains,
>from such mature technology.
Consider, also, that HD capacity increases are subject to big leaps
when a new technology is introduced, followed by a plateau until the
next leap. Flash-memory capacity, on the other hand, inexorably
increases according to Moore's Law.
Allen
that they have 500Gb Maxtor SATA drive for $130, which further confirms
Roger's price. I remember buying many 30 MEGAbyte drives back in the
1980s for more than that; I had unwillingly become my company's PC guru
and installed those same drives. I also remember the 7.5 Mb packs (six
discs, 10 usable surfaces) to use on mainframe drives in the late 1960s,
at around $650 each. Please, don't anyone tell me that drive prices
are static.
Allen
Dave Martindale
>Pretty much, drive speeds have gone up in step with drive capacities.
>You get greater capacity either with more platters or a higher data density.
>Both translate to greater throughput given the same rotational speed.
No, drive speeds go up with about the square root of drive capacity.
Capacity increases with higher track density on a platter, more
platters, and higher data density along the track. Only the latter
increases data rate given the same rotational speed. The other two
factors only increase the total number of tracks.
Dave
AZ Nomad
>AZ Nomad <azno...@PremoveOBthisOX.COM> writes:
>>Pretty much, drive speeds have gone up in step with drive capacities.
>>You get greater capacity either with more platters or a higher data density.
>>Both translate to greater throughput given the same rotational speed.
>No, drive speeds go up with about the square root of drive capacity.
>Capacity increases with higher track density on a platter, more
>platters, and higher data density along the track. Only the latter
The number of platters hasn't increased over the years. The top capacity
drives have more platters than entry level drives, but the number of
platters used hasn't increased over the last twenty years.
You're not going to find a drive with eighty platters. :-)
J. Clarke
The pace of progress in the disk industry seems to have slowed. It used
to be that new drives came in around $400 or so and dropped out around
$40 or so. But the 500s are approaching the $100 mark and the 750s are
under $200 with no next generation yet on the market--the terabyte
drives are supposed to be out this month I understand at around
$400--they may very well hit the sub $100 range before the next
generation ships.
--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)
Folkert Rienstra
> On Wed, 7 Mar 2007 18:37:35 +0000 (UTC), Dave Martindale <da...@cs.ubc.ca> wrote:
> > AZ Nomad <azno...@PremoveOBthisOX.COM> writes:
>
> > > Pretty much, drive speeds have gone up in step with drive capacities.
> > > You get greater capacity either with more platters or a higher data density.
> > > Both translate to greater throughput given the same rotational speed.
>
> > No, drive speeds go up with about the square root of drive capacity.
> > Capacity increases with higher track density on a platter, more
> > platters, and higher data density along the track. Only the latter
> The number of platters hasn't increased over the years.
It fluctuates.
> The top capacity drives have more platters than entry level drives,
But they didn't use the maximum number of platters possible for a long time.
> but the number of platters used hasn't increased over the last twenty years.
Oh, yes it did.
> You're not going to find a drive with eighty platters. :-)
But you may find them with the maximum number that can fit within a standard
half height drive. But then, with perpendicular recording now, the need for that
may be over for quite a while again.
Folkert Rienstra
> AZ Nomad <azno...@PremoveOBthisOX.COM> writes:
>
> > Pretty much, drive speeds have gone up in step with drive capacities.
> > You get greater capacity either with more platters or a higher data density.
> > Both translate to greater throughput given the same rotational speed.
>
> No, drive speeds go up with about the square root of drive capacity.
Platter capacity.
AZ Nomad
>AZ Nomad <azno...@PremoveOBthisOX.COM> writes:
You're right about performance going up w/ the square root of capacity...
Think of tracks*data_density*platters as data in three dimensions.
The platters is pretty much fixed; track density and data density have both
improved. Only data density improves performance. You can only
read one track at a time.
ASAAR
> You're right about performance going up w/ the square root of capacity...
> Think of tracks*data_density*platters as data in three dimensions.
> The platters is pretty much fixed; track density and data density have both
> improved. Only data density improves performance. You can only
> read one track at a time.
One head can only read one track at a time, but I recall reading
about drives that had two or three read/write heads. This might
have been 15 or more years ago, so I don't recall whether the heads
were constrained to the same track, but I don't think so. IIRC,
there were independent actuators. I'm sure that these drives were
out of my price range, nor were they likely to be the MFM and RLL
drives that I used back then.
Bob Willard
Standard practice is multiple heads per cylinder (one head per surface),
but only one active R/W head at a time, so only one set of R/W channel
electronics is needed.
In the 80's, there was at least one rather expensive HD (ISIS) with parallel
R/W channels, but only one shared actuator. Great for STR, but no help
for seek time.
In the 60's, there was at least one HD (IBM 1301)which offered multiple
actuators, which potentially gave improved STR as well as improved seek time.
But IIRC, the max. seek time on that huge beast was still seven seconds:
the time to recirculate the oil in the hydraulic adder (sometimes needed
to remove oil bubbles).
In the 50's (the dawn of HD time), the IBM 350 had one actuator and two
(IIRC) heads for its 25-platter assembly. For a short seek, the actuator
moved in or out along the radius of the platter stack; for a long seek,
the actuator moved out beyond the platter stack, then up or down parallel
to the central shaft, then in to the desired platter and cylinder. Seek
times were rather long, but still beat the snot out of the competition,
which was mag. tape.
--
Cheers, Bob
ASAAR
>> One head can only read one track at a time, but I recall reading
>> about drives that had two or three read/write heads. This might
>> have been 15 or more years ago, so I don't recall whether the heads
>> were constrained to the same track, but I don't think so. IIRC,
>> there were independent actuators. I'm sure that these drives were
>> out of my price range, nor were they likely to be the MFM and RLL
>> drives that I used back then.
>
> Standard practice is multiple heads per cylinder (one head per surface),
> but only one active R/W head at a time, so only one set of R/W channel
> electronics is needed.
Well of course I've never heard of a drive that didn't have a head
per platter surface. Seek time between surfaces would really suffer
if a disk drive resembled a one head per cylinder carousel. <g>
The ones I heard of with multiple sets of heads probably had only a
single set of R/W channel electronics per stack of heads, but a set
for every stack of heads. Although they could have been completely
independent, I imagine that when the channels were active, they were
all servicing the same track on the same platter surface, buffering
the entire track and of course allowing the complete track to be
read in a fraction of the normal time.
Rod Speed
"Bob Willard" <Bobw...@TrashThis.comcast.net> wrote in message
news:huSdnU9mNLskZXLY...@comcast.com...
And the DEC RS09 had fixed heads, one per track, literally.
Folkert Rienstra
> On Wed, 7 Mar 2007 18:37:35 +0000 (UTC), Dave Martindale <da...@cs.ubc.ca> wrote:
>
>
> > AZ Nomad <azno...@PremoveOBthisOX.COM> writes:
>
> > > Pretty much, drive speeds have gone up in step with drive capacities.
> > > You get greater capacity either with more platters or a higher data density.
> > > Both translate to greater throughput given the same rotational speed.
>
> > No, drive speeds go up with about the square root of drive capacity.
> > Capacity increases with higher track density on a platter, more
> > platters, and higher data density along the track. Only the latter
> > increases data rate given the same rotational speed. The other two
> > factors only increase the total number of tracks.
>
> You're right about performance going up w/ the square root of capacity...
Platter capacity.
> Think of tracks*data_density*platters as data in three dimensions.
> The platters is pretty much fixed;
> track density and data density have both improved.
> Only data density improves performance.
Right, so much for your:
"You're right about performance going up w/ the square root of capacity"
> You can only read one track at a time.
Roger
wrote:
>John Turco wrote:
>
>>Hard disks have been around far longer, than flash memory. Hence, it's
>>unrealistic to expect the same kinds of rapid price/performance gains,
>>from such mature technology.
>
>Consider, also, that HD capacity increases are subject to big leaps
>when a new technology is introduced, followed by a plateau until the
Such as the recent change to using vertical magnetic domains instead
of horizontal. I think all the new SATA drives are already using
this.
>next leap. Flash-memory capacity, on the other hand, inexorably
>increases according to Moore's Law.
C J Campbell
>
> I tried winzip and winrar but they cant compress them much. Is there
> anything else which works?
They can't be compressed much. Nikon offers a 'compressed' RAW format
in-camera. I can't tell the difference from the non-compressed one.
They are the same size. Besides, you really don't want to do anything
that might modify an original RAW file.
--
Waddling Eagle
World Famous Flight Instructor
Scubabix
"C J Campbell" <christoph...@hotmail.com> wrote in message
news:2007031007495627544-christophercampbell@hotmailcom...
uncompressed image. If you want it smaller, just convert it to a JPEG.
Rob
Dave Martindale
>> You're right about performance going up w/ the square root of capacity...
>Platter capacity.
That's the most correct answer, but you can't tell the platter capacity
from the outside of the drive, just the overall capacity.
On the other hand, as long as you compare drives of the same physical
size, which are the highest capacity in their "family", the number of
platters remains about the same, and so platter capacity is roughly
proportional to drive capacity.
On the other hand, if you compare today's 80 MB drive to an 80 MB drive
from 5 years ago, the latter probably has 3 or 4X as many surfaces as
the former.
Dave
CJT
I doubt you can find an example of "today's 80 MB drive" to compare with.
--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form che...@prodigy.net.
fy4...@gmail.com
> I tried winzip and winrar but they cant compress them much. Is there
> anything else which works?
Doug McDonald
> Why would you want to compress a RAW file anyway?
To save space.
> The idea is to have an
> uncompressed image. If you want it smaller, just convert it to a JPEG.
HUH? The idea is to have an image that is an exact representation of
what the camera saw. Compression is good if it is reversible. The Canon
CR2 format clearly is compressed quite a bit and works well. You would
EXPECT most camera's raw format to compress well, if for no other reason than
it is 12 bit, which leaves 4 unused bits in each word. Not to mention that
the vast majority of picture are going to have quite of bit of area
that is sky, or painted wall, or a closeup of somebody's (hopefully nice
clear complexion) face, and all of these should compress well if done
right.
Doug McDonald
Sameer
wrote:
> On 2007-03-03 18:16:40 -0800, "Sameer" <sameerxah...@gmail.com> said:
>
> > I tried winzip and winrar but they cant compress them much. Is there
> > anything else which works?
>
> They can't be compressed much. Nikon offers a 'compressed' RAW format
> in-camera. I can't tell the difference from the non-compressed one.
> They are the same size. Besides, you really don't want to do anything
> that might modify an original RAW file.
That is why I decided not to use DNG files just to save space.
Barry Pearson
wrote:
[snip]
> Besides, you really don't want to do anything
> that might modify an original RAW file.
Why not? (Please don't say something silly about "your digital
negative"!)
Lots of things modify original raw files, typically by changing
metadata within them.
What matters is preserving the raw image data - NOT the raw file.
--
Barry Pearson
http://www.barrypearson.co.uk/photography/
Folkert Rienstra
> "Folkert Rienstra" <folkertxx...@wanadoo.nl> writes:
You are posting the Reply-to address instead of the From address.
>
> > > You're right about performance going up w/ the square root of capacity...
>
> > Platter capacity.
> That's the most correct answer,
On rethink, that should have read 'surface capacity'.
The smallest drive in the range may even use only one
surface or even only a partial surface.
> but you can't tell the platter capacity from the
> outside of the drive, just the overall capacity.
Which is no reason for making a wrong statement.
And I think that the square root means that a capacity increase is derived
from equal sector and track density increase. That may not be true either.
>
> On the other hand, as long as you compare drives of the same physical
> size, which are the highest capacity in their "family",
That sentence makes absolutely no sense. Presumably you mean
"same physical make-up", like same number of platters, heads, rpm etc.
> the number of platters remains about the same, and so platter capacity
> is roughly proportional to drive capacity.
Until you change to Perpendicular Recording and all bets are off again.
Roger
<see_re...@myweb.nl> wrote:
>"Dave Martindale" <da...@cs.ubc.ca> wrote in message news:esvmq7$oel$1...@swain.cs.ubc.ca
>> "Folkert Rienstra" <folkertxx...@wanadoo.nl> writes:
<snip>
>
>Until you change to Perpendicular Recording and all bets are off again.
Any of the new drives now on the market not perpendicular?
>
>>
>> On the other hand, if you compare today's 80 MB drive to an 80 MB drive
>> from 5 years ago, the latter probably has 3 or 4X as many surfaces as
>> the former.
>>
>> Dave
AZ Nomad
>On Mon, 12 Mar 2007 00:24:41 +0100, "Folkert Rienstra"
><see_re...@myweb.nl> wrote:
>>"Dave Martindale" <da...@cs.ubc.ca> wrote in message news:esvmq7$oel$1...@swain.cs.ubc.ca
>>> "Folkert Rienstra" <folkertxx...@wanadoo.nl> writes:
><snip>
>>
>>Until you change to Perpendicular Recording and all bets are off again.
>Any of the new drives now on the market not perpendicular?
Most of them.
There's only one that advertises perpendicular magnetic orientation and
that the seagate 750gb.
Roger
They hit the net around the first of this month or about two weeks
ago. They are showing up as external drives as the current belief is
they will start out as back up storage rather than live storage.
Prices are $400 give or take $20 or $30. Reviews are mixed. Sizes I've
seen so far go up to 1.28 Terabytes. So far I've only seen USB2 and
Firewire when this just begs e-SATA at 3 Gbs compared to USB2 and
Firewire speeds.
Cost per unit volume is *about* 40 to near 50 cents per Gig while a
pair of 500 Sata 3 drives will give about 28 cents per Gig. OTOH if
you include two 500 Gig drives and external enclosures it's 36 cents
per Gig.
I've not seen any of the "big name" brands in the Terabyte range yet.
I'm also seeing the marriage of flash memory with hard drives where
the flash memory is used as the cache. That lets us go from 8 to 16
meg cache to several gigs in the same space. How much is going to be
available is yet to be seen.
>$400--they may very well hit the sub $100 range before the next
>generation ships.
>--
J. Clarke
'Fraid not. The only terabyte drive that has been announced is a
terabyte, not 1.28 terabyte. Those external 1.28 TB "drives" for 400
bucks are arrays of two or three or four smaller drives with no
redundancy and range from kind of chancy to pure unadulterated crap. If
they called them what they are then I wouldn't have any problem with
them, but by calling them "drives" they imply that there's only a single
disk in there instead of an array that is several times more likely to
fail than a single disk.
I really wish the FTC would nail the bastards for false advertising.
> Cost per unit volume is *about* 40 to near 50 cents per Gig while a
> pair of 500 Sata 3 drives will give about 28 cents per Gig. OTOH if
> you include two 500 Gig drives and external enclosures it's 36 cents
> per Gig.
> I've not seen any of the "big name" brands in the Terabyte range yet.
And until you do, assume that any terabyte "drive" that is not a "big
name" is an array and that the manufacturer is lying to you about it
being a "drive".
> I'm also seeing the marriage of flash memory with hard drives where
> the flash memory is used as the cache. That lets us go from 8 to 16
> meg cache to several gigs in the same space. How much is going to be
> available is yet to be seen.
>> $400--they may very well hit the sub $100 range before the next
>> generation ships.
>> --
> Roger Halstead (K8RI & ARRL life member)
> (N833R, S# CD-2 Worlds oldest Debonair)
> www.rogerhalstead.com
--