Got <140 bit DR Image?
BradGuth
welding arc?
There’s truthworthy radar imaging of 4 to 36 looks per composite
pixel, then always good old conventional Kodak film with its nonlinear
spectrum and limited DR(dynamic range), and then there’s some rather
nifty CCD/CMOS imaging alternatives that requires by far the most
deductive observationology, especially if there are extreme DR and
various colour/hue saturations that need to be taken into account,
along with those unavoidable shadows and sometimes surface glare/
mirror like reflective considerations.
The finite number of pixels per given FOV isn’t the only truth worthy
holy grail of quality imaging, especially if there are issues of
dynamic range and color/hue saturation to consider. (usually there
are)
Instead of the Kodak/Fuji 10~11 db worth of DR, or the traditional <14
bit of high end cameras, whereas we now have <140 db/bit of extended DR
(dynamic range) via CMOS imaging that’s affordably off the shelf (so
to speak), plus absolutely terrific optical options in bandpass
filters, that'll look directly into a vibrant star (such as Sirius)
without losing the crisp detailed surface, horizon and of whatever is
in nearby orbit. Actually, nearly that kind of ccd/cmos pixel dynamic
range has existed and been in our public funded DARPA and NASA use for
quite some time, just not allowed to see the public light of day.
http://www.ims.fraunhofer.de/uploads/media/cmos_image_sensor_arrays_en_07.pdf
Camera A/D imaging converters are sort of where the technology buck
stops (so to speak), although more powerful and parallel CPUs tend to
make a 128 DB image doable, though a single scan 64 DB format might be
a practical upper limit/scan that only supercomputers could manage,
and perhaps 32 DB for stuff that’s taken on the fly (so to speak).
However, even by using a 16 DB A/D with such an extended dynamic range
capable CMOS imager is going to knock some eye-candy socks off, and if
need be via taking multiple scans, one of each 16 DB portion of the
available dynamic range should be more than good enough (4 scans could
extract 64 DB worth of dynamic range), although you’d likely need a
Blue Ray DVD for storing each image, especially if taken in full color
format, and worse yet if that spectrum happens to include some UV and
IR.
Keeping this little Fraunhofer CMOS imager within its thermal specs
(that’s wider than most as is), would be the only application
requirement in need of R&D for its custom packaging.
~ BG
WARNING!
I've never ever advocated kill filing anyone, ever. But if you give this
kook anything, he'll never stop. He is another version of Ed Conrad (the
retard who believes human bones hundreds of millions of years old turned up
in coal seams). Guth believes the Americans never went to the Moon and
that beings live on Venus. He's a nutcase.
This should be the ONLY response to this guy's posts.
Rome J.
wrote:
>What else can your camera see if its FOV is centered upon a TIG
>welding arc?
An inexpensive off-the-shelf Canon Powershot P&S camera (CCD sensor) with
CHDK installed can image a 30EV dynamic range with only 4 bracket shots.
These cameras can easily photograph the arc from a welder at 1/40,000
second shutter-speed, f/11, ISO50.
BradGuth
> On Tue, 27 Jan 2009 17:59:44 -0800 (PST), BradGuth <bradg...@gmail.com>
> wrote:
>
> >What else can your camera see if its FOV is centered upon a TIG
> >welding arc?
>
> An inexpensive off-the-shelf Canon Powershot P&S camera (CCD sensor) with
> CHDK installed can image a 30EV dynamic range with only 4 bracket shots.
> These cameras can easily photograph the arc from a welder at 1/40,000
> second shutter-speed, f/11, ISO50.
True, but at the 1/40,000th of a second scan and even with 4 bracket
shots there's practically nothing else to be seen in that image.
Take another look at the results of a true 140 bit CMOS imager.
http://www.ims.fraunhofer.de/uploads/media/cmos_image_sensor_arrays_en_07.pdf
~ BG
John McWilliams
Mr.T
"BradGuth" <brad...@gmail.com> wrote in message
news:91d2b411-84a4-44f3...@v5g2000pre.googlegroups.com...
On Jan 27, 6:55 pm, Rome J. <ro...@passingthrough.org> wrote:
>> >What else can your camera see if its FOV is centered upon a TIG
>> >welding arc?
>
>> An inexpensive off-the-shelf Canon Powershot P&S camera (CCD sensor) with
>> CHDK installed can image a 30EV dynamic range with only 4 bracket shots.
Better hope nothing moves during those 4 shots then. Not even the arc!
>> These cameras can easily photograph the arc from a welder at 1/40,000
>> second shutter-speed, f/11, ISO50.
>
>True, but at the 1/40,000th of a second scan and even with 4 bracket
>shots there's practically nothing else to be seen in that image.
Isn't that what the other 3 shots are for? Look up "HDR imaging".
MrT.
BradGuth
> "BradGuth" <bradg...@gmail.com> wrote in message
With the 140 db CMOS imager it's accomplished in one scan. In other
words, looking directly at Sirius ABC is no longer an issue of not
seing everything that's within the given FOV.
If need be, there are even cameras that can average 2<256 scans per
composite image, so even that's covered.
~ BG.
Mr.T
>With the 140 db CMOS imager it's accomplished in one scan.
Of course, just let me know when a similarly equipped camera is available to
the public at a couple of thousand dollars though.
Otherwise what's your point? :-)
BTW the incorrect/ad-hoc transposition of "bits" and "DB" makes the OP both
wrong and unreadable in any case!
MrT.
J. Clarke
Then there's the "<". My old Coolpix 990 has considerably < 140 dB
and why one would want a camera with < 140 bits is a mystery to me.
>
> MrT.
--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)
BradGuth
> "BradGuth" <bradg...@gmail.com> wrote in message
>
> news:40c9d7d4-2678-41b2...@f40g2000pri.googlegroups.com...
>
> >With the 140 db CMOS imager it's accomplished in one scan.
>
> Of course, just let me know when a similarly equipped camera is available to
> the public at a couple of thousand dollars though.
> Otherwise what's your point? :-)
If you can't figure out the obvious point, then what's the point?
>
> BTW the incorrect/ad-hoc transposition of "bits" and "DB" makes the OP both
> wrong and unreadable in any case!
>
> MrT.
My dyslexic mind isn't what it used to be, so sue me. In spite of
myself, you know exactly what I'd intended to convey. The A/D bits of
digital imaging was similar enough to the range of DR in db. Most
scientific cameras are A/D limited as to creating 16 bit image data,
although the 140 db worth of CMOS imager DR itself is simply pretty
hard to ignore.
BTW, bet there's a wrong word used somewhere in the constitution, or
in the bible, so either of those are thereby "unreadable in any
case!"?
~ BG
BradGuth
ABC? (140 db DR instead of 140 bit, via Mr.T)
There’s always the most truthworthy 8 bit radar imaging of 4 to 36
looks per composite pixel, then always we have good old conventional
Kodak or Fuji film with its nonlinear spectrum and rather limited DR
(dynamic range), and then there’s some rather nifty CCD/CMOS imaging
alternatives that requires by far the utmost of our best deductive
observationology, especially if there are extreme DR and various
colour/hue saturations that need to be taken into account unless
excluding suits your fancy, along with those unavoidable shadows and
sometimes surface glare/mirror like reflective considerations.
The finite number of pixels as per any given FOV isn’t the only
truthworthy holy grail of quality and truthworthy imaging, especially
if there are complex issues of dynamic range and color/hue saturation
to consider(usually there are), meaning that it’s sometimes a whole
lot better having extended DR rather than any given raw number of
pixels.
Instead of the Kodak/Fuji 10~11 db worth of DR, or the traditional <14
bit of high end cameras, whereas we now have <140 db of extended DR
(dynamic range) via CMOS imaging that’s affordably off the shelf (so
to speak), plus absolutely terrific optical options in bandpass
filters, that'll look directly into a vibrant nearby star (such as
Sirius) without losing the crisp detailed surface, horizon and of
whatever is in nearby orbit, such as Sirius C along with whatever
moons. Actually, nearly that kind of ccd/cmos pixel dynamic range has
existed and been in our public funded DARPA and NASA use for quite
some time, just not ever allowed to see the public light of day.
http://www.ims.fraunhofer.de/uploads/media/cmos_image_sensor_arrays_en_07.pdf
Camera A/D imaging converters are sort of where the technology buck
stops (so to speak), although more powerful and parallel CPUs tend to
make a 128 bit image doable, though a single scan 64 bit format might
be a practical upper limit/scan that only supercomputers could manage,
and perhaps 32 bit for stuff that’s taken on the fly (so to speak).
However, even by using a 16 bit A/D with such an extended dynamic
range capable CMOS imager is going to knock some eye-candy socks off,
and if need be via taking multiple scans, such as one of each 16 DB
portion of the available dynamic range should be more than good
enough (4 scans could extract 64 DB worth of dynamic range), although
you’d likely need a Blue Ray DVD for storing each image, especially if
taken in full color format, and worse yet if that spectrum happens to
include some UV and IR.
Keeping this little Fraunhofer CMOS imager within its thermal specs
(that’s wider than most as is), would be the only application
requirement in need of R&D for its custom packaging for also blocking
as much other unwanted radiation as possible.
~ BG
Mr.T
"J. Clarke" <jclarke...@cox.net> wrote in message
news:glqm9...@news4.newsguy.com...
> Then there's the "<". My old Coolpix 990 has considerably < 140 dB
> and why one would want a camera with < 140 bits is a mystery to me.
Gee even the best SLR's only do ~14 bits per channel, or 42 bits per pixel
atm.
But there still seem to be a lot of people who do want (or will happily
accept) "<140 bits DR".
MrT.
Mr.T
>> BTW the incorrect/ad-hoc transposition of "bits" and "DB" makes the OP
both
>> wrong and unreadable in any case!
>My dyslexic mind isn't what it used to be, so sue me. In spite of
>myself, you know exactly what I'd intended to convey.
Not so, or we wouldn't be arguing where you are technically wrong and/or
technically obtuse.
> The A/D bits of
>digital imaging was similar enough to the range of DR in db.
Not as an equivalent figure they are not, 1 bit =~6dB and therefore dB is
not the same as the number of stops either.
>Most
>scientific cameras are A/D limited as to creating 16 bit image data,
>although the 140 db worth of CMOS imager DR itself is simply pretty
>hard to ignore.
There are sample shifting techniques that can use 16 bit A/D's to provide 32
bit data, more than enough for 140dB sensors.
MrT.
Floyd L. Davidson
>"J. Clarke" <jclarke...@cox.net> wrote in message
>news:glqm9...@news4.newsguy.com...
>> Then there's the "<". My old Coolpix 990 has considerably < 140 dB
>> and why one would want a camera with < 140 bits is a mystery to me.
>
>Gee even the best SLR's only do ~14 bits per channel, or 42 bits per pixel
>atm.
That is *not* 14 bits per "channel", as there are no
channels. It's simply 14 bits per "pixel". (It isn't
really a pixel either, it's 14 bits per sensor
location.)
To actually capture a 140 dB dynamic range requires a
minimum of 23 bits per sensor data sample.
>But there still seem to be a lot of people who do want (or will happily
>accept) "<140 bits DR".
:-)
We don't want to hold our breath waiting for a 24 bit ADC?
--
Floyd L. Davidson <http://www.apaflo.com/floyd_davidson>
Ukpeagvik (Barrow, Alaska) fl...@apaflo.com
nospam
<fl...@apaflo.com> wrote:
> >Gee even the best SLR's only do ~14 bits per channel, or 42 bits per pixel
> >atm.
>
> That is *not* 14 bits per "channel", as there are no
> channels. It's simply 14 bits per "pixel". (It isn't
> really a pixel either, it's 14 bits per sensor
> location.)
i've seen it called sensel, for sensor element.
> We don't want to hold our breath waiting for a 24 bit ADC?
is 22 bit enough? :)
<http://www.pentax.jp/english/imaging/digital/slr/k10d/feature.html>
however, phil is a bit skeptical (as are many others):
<http://www.dpreview.com/reviews/pentaxk10d/>
Mr.T
"Floyd L. Davidson" <fl...@apaflo.com> wrote in message
news:877i4eo...@apaflo.com...
> >Gee even the best SLR's only do ~14 bits per channel, or 42 bits per
pixel
> >atm.
>
> That is *not* 14 bits per "channel", as there are no
> channels. It's simply 14 bits per "pixel".
If it's just luminosity then it's often referred to as an "alpha channel",
and yes 14 bits per single channel pixel is..... 14 bits.
>(It isn't really a pixel either, it's 14 bits per sensor
> location.)
Can you explain this differentiation further, I'm not sure what you are
getting at, but have no experience with astronomical imaging. Doesn't a
sensor location map to a picture element location as with other cameras?
> >But there still seem to be a lot of people who do want (or will happily
> >accept) "<140 bits DR". :-)
>
> We don't want to hold our breath waiting for a 24 bit ADC?
Fortunately it's not necessary then.
MrT.
BradGuth
> "BradGuth" <bradg...@gmail.com> wrote in message
Thanks for that informative feedback, as I certainly didn't understand
what it would take in order to fully realize the maximum 140 db
imaging capability. This should mean our consumer video products
should soon incorporate at least this much or better DR, and thus
images of Sirius shouldn't be over saturated to the point of losing a
good look-see at Sirius C, especially if certain optical bandpass
elements are utilized.
~ BG
BradGuth
>
> Camera A/D imaging converters are sort of where the technology buck
> stops (so to speak), although more powerful and parallel CPUs tend to
> make a 128 bit image doable, though a single scan 64 bit format might
> be a practical upper limit/scan that only supercomputers could manage,
> and perhaps 32 bit for stuff that’s taken on the fly (so to speak).
> However, even by using a 16 bit A/D with such an extended dynamic
> range capable CMOS imager is going to knock some eye-candy socks off,
> and if need be via taking multiple scans, such as one of each 16 DB
> portion of the available dynamic range should be more than good
> enough (4 scans could extract 64 DB worth of dynamic range), although
> you’d likely need a Blue Ray DVD for storing each image, especially if
> taken in full color format, and worse yet if that spectrum happens to
> include some UV and IR.
>
> Keeping this little Fraunhofer CMOS imager within its thermal specs
> (that’s wider than most as is), would be the only application
> requirement in need of R&D for its custom packaging for also blocking
> as much other unwanted radiation as possible.
>
> ~ BG
The matter of fact that anyone can systematically exclude as much DR
(dynamic range) as you like, so as to minimize whatever contrast or
color/hue saturation in order to exclude other information that’s
above or below a specified range, isn’t new. It seems our NASA has
for decades used this method whenever there were other secondary
planets and/or major stars within a given FOV(frame of view) of
whatever primary asteroid, planet or moon, such as their having
excluded Venus, Mars, Jupiter and Saturn whenever found above the
physically dark as coal Selene/moon horizon.
Of course there are a few exceptions where they’d forgotten to do this
prior to getting published, so as even that of the limited DR of film
easily shows other planets plus a few of the brightest stars besides
just depicting Earth outside of our physically dark moon. The fairly
old (1994) Clementine mission offers a perfectly good DR example of
that era CCD recording our moon, Venus and sun all in the same FOV
that got published. Of course the public hardly ever gets to see but
at most 0.1% of any given mission images, and even less of the other
science, so it’s hard to tell how many original or better examples
exist outside of their terrific mineralogy imaging that’s only now
getting outdone by ISRO.
Low and higher resolution versions of the moon, Venus and sun (notice
the Earthshine illuminated moon, and the more proper color/hue
saturation of Venus when viewed from outside our atmosphere):
http://goes.gsfc.nasa.gov/pub/goes/clementine.venus.sun.emoon.jpeg
http://www.nrl.navy.mil/NewsRoom/images/clem.jpg
http://www.nrl.navy.mil/NewsRoom/images/clem.tif
Now try to imagine a FOV of our moon plus Earth and Venus, as could
easily have been obtained via Apollo missions (via orbiting or EVAs)
A11, A14 and A16, as having easily excluded the sun and thereby having
a full color saturation and terrific contrast of just Earth and Venus
above the dark as coal lunar horizon. Oddly that never happened.
Future missions that’ll have the 140 db or better scope of DR and
faster scans should offer impressive results, especially of the
complex mineralogy of our moon. Too bad the new and improved Hubble
imagers are not this good, but other orbiting cameras should equal or
likely exceed this level of DR, and subsequently getting terrific
images of Sirius C along with whatever moons.
According to MrT, “There are sample shifting techniques that can use
16 bit A/D's to provide 32 bit data, more than enough for 140dB
sensors.”
~ Brad Guth Brad_Guth Brad.Guth BradGuth BG / “Guth Usenet”
BradGuth
> "J. Clarke" <jclarke.use...@cox.net> wrote in message
True, as you'll most likely never have to make use of the full DR,
although whenever the sun or that of a directed glare of the sun gets
in the FOV, it certainly would be nice not having the image entirely
saturated with solar photons, as well as peering into deep shadows at
the same time.
Your 6 bits per cmos imager DB even sounds terrific. I suppose what's
next will be the 256 db imager and 21 bit A/D processor, along with a
terabyte in media storage capacity, plus 100:1 zoom optics including
many nifty bandpass filter options, all for under a few grand.
~ BG
BradGuth
Perhaps no breath holding is necessary.
Using 2 or 4 quick scans per image could make the 16 bit ADC more
viable for the 140 db cmos imager. There's at least one commercial/
science camera that can selectively average up to 256 scans per output
image.
~ BG
BradGuth
> "Floyd L. Davidson" <fl...@apaflo.com> wrote in messagenews:877i4eo...@apaflo.com...
> > Floyd L. Davidson:
> > That is *not* 14 bits per "channel", as there are no channels.
> > It's simply 14 bits per "pixel". (It isn't really a pixel either, it's
> > 14 bits per sensor location.)
“To actually capture a 140 dB dynamic range requires a minimum of 23
bits per sensor data sample. We don't want to hold our breath waiting
for a 24 bit ADC?”
Perhaps no breath holding is going to be necessary.
Using 2 or 4 quick scans per image could make the existing 16 bit ADC
more viable for utilizing the 140 db cmos imager. There's at least
one commercial/science camera that can selectively average from 2 <
256 scans per output image, and that’s purely software.
~ BG
BradGuth
> > Floyd L. Davidson:
“To actually capture a 140 dB dynamic range requires a minimum of 23
bits per sensor data sample. We don't want to hold our breath waiting
for a 24 bit ADC?”
Perhaps no breath holding is going to be necessary.
Using 2 or 4 quick scans per image could make the existing 16 bit ADC
more viable for utilizing the 140 db cmos imager. There's at least
one commercial/science camera that can selectively average from 2 <
256 scans per output image, and I believe that’s purely software.
~ BG
Floyd L. Davidson
People are commonly using HDL with modern DSLR's to
achieve greater dynamic range. In theory a Nikon D3 can
get about 12 fstops, so two images would suffice. In
practice of course it takes 3.
BradGuth
At 6 db per bit, we may need a 23+ bit ADC, or perhaps not.
> Floyd L. Davidson:
“To actually capture a 140 dB dynamic range requires a minimum of 23
bits per sensor data sample. We don't want to hold our breath waiting
for a 24 bit ADC?”
Perhaps no breath holding is going to be necessary.
Using 2 or 4 quick scans of “sample shifting techniques” per composite
image that could make the existing 16 bit ADC more viable for
utilizing the 140 db cmos imager (a 24 bit composite needing as little
as only two 12 bit scans). There's at least one off-the-shelf
commercial/science camera that can selectively average from 2 < 256
scans or frames per composite output image. I believe that’s
accomplished either via BASLER proprietary firmware or purely
software, and I’m certain by now there are much higher resolution
cameras capable of the same.
http://www.baslerweb.com/beitraege/news_en_77572.html
A 16 bit ADC using the dual scanned and sample shifted composite image
as its output, as such could muster up enough collective processing in
order to utilize an imager that’s offering <192 db of DR.
~ BG
John O'Flaherty
The link you provided gives several hints about how they achieve wide
dynamic range-
Page 2: "...the CMOS imaging approach also provides the choice between
linear and logarithmic pixel readout characteristics, random pixel
access..."
Page 1, Fig 2, (5) "Locally adaptive - 128 * 128 pixels, logarithmic
readout, on-chip local brightness adaptation""
Page 2, Fig 3: "...CMOS camera with individual exposure time
selection"
If they can control both exposure time and sensitivity (ISO)
individually for small blocks of pixels, and read them
logarithmically, the wide irradiance range is less astonishing.
--
John
Mr.T
>Thanks for that informative feedback, as I certainly didn't understand
>what it would take in order to fully realize the maximum 140 db
>imaging capability. This should mean our consumer video products
>should soon incorporate at least this much or better DR
I wouldn't want to hold my breathe if I were you :-)
But I do expect we will get to true 16 bit capture before too long, at which
point most people will be more than happy.
MrT.
Mr.T
>Your 6 bits per cmos imager DB even sounds terrific.
Thats 6 dB per bit which is simple mathematics, nothing more.
> I suppose what's
>next will be the 256 db imager and 21 bit A/D processor,
Would need at least 2 in that case.
>along with a
>terabyte in media storage capacity, plus 100:1 zoom optics including
>many nifty bandpass filter options, all for under a few grand.
You are aware of the concept of market demand?
*IF* you think there is sufficient demand for the above, it may even happen.
But maybe not in our lifetime :-)
MrT.
Mr.T
>Perhaps no breath holding is necessary.
>Using 2 or 4 quick scans per image could make the 16 bit ADC more
>viable for the 140 db cmos imager. There's at least one commercial/
>science camera that can selectively average up to 256 scans per output
>image.
Multiple scans are only necessary for sensor limitations, not A/D
limitations. If the imager *can* provide 140dB DNR in one pass, then no
extra scans are necessary to capture more than 16bits of data.
MrT.
BradGuth
> "BradGuth" <bradg...@gmail.com> wrote in message
And as you've suggested, a pair of 16 bit captures could also take
full advantage of the 140 db worth of DR, or even up to 192 db should
a given cmos imager offer as much. In other words, at 192 db of
dynamic range (similar to the best human eye), black would likely
never be recorded as entirely black, and any direct look at the sun
would never white-out or much less bloom or bleed over any other
pixels.
~ BG
Mr.T
>And as you've suggested, a pair of 16 bit captures could also take
>full advantage of the 140 db worth of DR, or even up to 192 db should
>a given cmos imager offer as much.
No, I said extra scans are unnecessary *if* your sensor provides 140dB in
one scan. Simply use 2 or more A/D's.
> In other words, at 192 db of
>dynamic range (similar to the best human eye),
The best human eye cannot manage that range in one pass either. It can only
do so by adjusting the pupil diameter. But then the problem of the eyes
color accuracy at extreme sensitivities goes to hell in any case.
Just as it is now possible to record audio with more accuracy than human
hearing, it should be possible to record images with more accuracy than
human vision in the foreseeable future, IMO. The only thing missing at the
moment is suitable sensors AFAICT. Possibly not even that :-)
Of course you do realise such an image can never be printed with even the
slightest accuracy?
MrT.
BradGuth
> "BradGuth" <bradg...@gmail.com> wrote in message
>
> news:3e1fa2bf-f230-4a37...@s9g2000prg.googlegroups.com...
>
> >And as you've suggested, a pair of 16 bit captures could also take
> >full advantage of the 140 db worth of DR, or even up to 192 db should
> >a given cmos imager offer as much.
>
> No, I said extra scans are unnecessary *if* your sensor provides 140dB in
> one scan. Simply use 2 or more A/D's.
That's even better, because 12 bit ADCs are relatively dirt cheap, and
16 bit can't be all that much worse off. Fast terabyte media storage
could get a little spendy.
>
> > In other words, at 192 db of
> >dynamic range (similar to the best human eye),
>
> The best human eye cannot manage that range in one pass either. It can only
> do so by adjusting the pupil diameter. But then the problem of the eyes
> color accuracy at extreme sensitivities goes to hell in any case.
I agree, the 140 db of the cmos imager would always far outperform the
human eye, not to mention at < ten thousand fold faster response.
>
> Just as it is now possible to record audio with more accuracy than human
> hearing, it should be possible to record images with more accuracy than
> human vision in the foreseeable future, IMO. The only thing missing at the
> moment is suitable sensors AFAICT. Possibly not even that :-)
>
> Of course you do realise such an image can never be printed with even the
> slightest accuracy?
>
> MrT.
Image accuracy is always the eye candy that's in the eye of the
beholder. I've called it observationology, and it's entirely
subjective as well as in need of deductively interpreting no matter
how good or bad the image technology is. If you can't deductively
think and thus interpret for yourself, you're kind of screwed into
accepting whatever others (your peers) have to say. Unlike most, I
still like to think for myself, and I never saw one stinking image of
anything looking WMD worthy, but then I'm not as smart as our SEC and
Madoff either.
~ BG
Vance
Do you actually pictures?
Bhogi
<no.j...@spammers.virginiaquilter.allowed.com> wrote:
> On Thu, 29 Jan 2009 04:54:14 -0800 (PST), BradGuth
>
> I wonder how the engineers might go about that.
No need for floating point. I don't think there's a dslr that can
collect more than 65000 electrons per pixel. Smaller pixels can hold
even less. All you need is a 16bit A/D at unity sensitvity (1 electron
= 1 numerically).
BradGuth
I do not have such pictures. However, pictures of Sirius C should
have become a snap, that is unless there's nothing of any .06 solar
mass that's causing such a pronounced pattern of Sirius A/B
interactions.
Possibly it's a micro black hole, although I'd kind of doubt it. It's
more likely a brown or possibly red dwarf.
There are 200 DB cmos imagers, and with either dual 16 bit ADCs or
simply selectively double scanning via one such 16 bit ADC should more
than do the trick of extracting whatever Sirius C has to offer. Even
at 12 DB per ADC bit wouldn't be out of the question, although
multiple ADCs seems rather doable.
~ BG
BradGuth
> "BradGuth" <bradg...@gmail.com> wrote in message
That has been said about many things, although better imaging
capability is likely to far outperform our wildest expectations, and a
whole lot sooner than we might think. Such as a 200 DB cmos imager
using 2.5-µm pixels could happen within another year or so.
At any rate, even a 100 DB cmos imager using a 16 bit ADC and
sufficient bandpass filters should be capable of pulling Sirius C our
from all the Sirius A/B noise. Quite possibly Sirius C is either a
brown dwarf of < 0.06 solar mass, or it's some kind of massive planet.
~ BG
John Sheehy
news:d4a248b5-b719-46ac...@e1g2000pra.googlegroups.com:
> No need for floating point. I don't think there's a dslr that can
> collect more than 65000 electrons per pixel. Smaller pixels can hold
> even less. All you need is a 16bit A/D at unity sensitvity (1 electron
> = 1 numerically).
The Canon 5D and 1D2 have a maximum of about 80,000, at "ISO 50".
Pixel density has move higher, without well depth increasing with the newer
models, so new FWCs are much lower. A breakthrough in well depth will be
needed before FWCs start climbing again.
John O'Flaherty
wrote:
Do you actually English?
--
John
Alan Browne
> Do you actually English?
The usenet editor position was abolished a long time ago.
BradGuth
wrote:
> John O'Flaherty wrote:
> > Do you actually English?
>
> The usenet editor position was abolished a long time ago.
Why are you doing this kind of Usenet/newsgroup damage control?
Aren't these clowns of the brown-nosed status quo capable of defending
their own actions?
Is our John O'Flaherty simply not familiar with optics, image sensors
and the kinds of fully processed end results?
And, don't birds of a feather usually flock together?
~ BG
John O'Flaherty
About the time the censor was dismissed?
--
John
Mr.T
>That has been said about many things, although better imaging
>capability is likely to far outperform our wildest expectations, and a
>whole lot sooner than we might think.
No argument that imaging will rapidly improve, the problem is that I don't
think you realise what you are asking for if applied to general photography.
>Such as a 200 DB cmos imager
>using 2.5-痠 pixels could happen within another year or so.
But will average people readilly accept a liquid helium cooled camera? :-)
>At any rate, even a 100 DB cmos imager using a 16 bit ADC and
>sufficient bandpass filters should be capable of pulling Sirius C our
>from all the Sirius A/B noise. Quite possibly Sirius C is either a
>brown dwarf of < 0.06 solar mass, or it's some kind of massive planet.
OK, just don't get highly specialised scientific fields with mega budgets
mixed up with general photography. Sure there is some spin off, but there
are also absolute physical limitations to be considered.
MrT.
J. Clarke
> "BradGuth" <brad...@gmail.com> wrote in message
> news:ad604382-54f8-485b...@w1g2000prm.googlegroups.com...
>> That has been said about many things, although better imaging
>> capability is likely to far outperform our wildest expectations,
>> and
>> a whole lot sooner than we might think.
>
> No argument that imaging will rapidly improve, the problem is that I
> don't think you realise what you are asking for if applied to
> general
> photography.
>
>> Such as a 200 DB cmos imager
>
> But will average people readilly accept a liquid helium cooled
> camera? :-)
>
>
>> At any rate, even a 100 DB cmos imager using a 16 bit ADC and
>> sufficient bandpass filters should be capable of pulling Sirius C
>> our
>> from all the Sirius A/B noise. Quite possibly Sirius C is either a
>> brown dwarf of < 0.06 solar mass, or it's some kind of massive
>> planet.
>
> OK, just don't get highly specialised scientific fields with mega
> budgets mixed up with general photography. Sure there is some spin
> off, but there are also absolute physical limitations to be
> considered.
The silly part of this is that with all the super-whizzbang
technology, there's still going to be a tree growing out of Aunt
Maudie's head as she's caught in mid sneeze.
--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)
BradGuth
> "BradGuth" <bradg...@gmail.com> wrote in message
>
> news:ad604382-54f8-485b...@w1g2000prm.googlegroups.com...
>
> >That has been said about many things, although better imaging
> >capability is likely to far outperform our wildest expectations, and a
> >whole lot sooner than we might think.
>
> No argument that imaging will rapidly improve, the problem is that I don't
> think you realise what you are asking for if applied to general photography.
>
> >Such as a 200 DB cmos imager
>
> But will average people readilly accept a liquid helium cooled camera? :-)
I would, as would anyone looking for brown dwarfs.
>
> >At any rate, even a 100 DB cmos imager using a 16 bit ADC and
> >sufficient bandpass filters should be capable of pulling Sirius C our
> >from all the Sirius A/B noise. Quite possibly Sirius C is either a
> >brown dwarf of < 0.06 solar mass, or it's some kind of massive planet.
>
> OK, just don't get highly specialised scientific fields with mega budgets
> mixed up with general photography. Sure there is some spin off, but there
> are also absolute physical limitations to be considered.
>
> MrT.
Trust me, sufficient DR of cmos imagers exist as is, and it isn't even
all that spendy.
~ BG
Mr.T
>> >Such as a 200 DB cmos imager
>> But will average people readilly accept a liquid helium cooled camera?
:-)
>I would, as would anyone looking for brown dwarfs.
Just as I said, highly specialised fields only. Lets not confuse it with
general photography however.
>Trust me, sufficient DR of cmos imagers exist as is, and it isn't even
>all that spendy.
I suggest you find out what is actually necessary to produce a 200dB range
of output from such a sensor!
I can't see it happening anytime soon. Multiple scan is the accepted
practical method of obtaining such a range.
But do let us know when you actually purchase an imager with a single pass
200dB range :-)
MrT.
Bhogi
I stand corrected, we need 17bit A/D converters :)
Hm, that's strange. I was always under the impression that FWC was
independent of ISO and ISO was just a window to the sensor data,
capturing the highest values at low ISOs and lowest at high ISOs...
apart from ISO being a convenience for the user to help set "correct"
exposure times at different lighting conditions.
BradGuth
> "BradGuth" <bradg...@gmail.com> wrote in message
>
> news:d1863fb6-9359-49e3...@35g2000pry.googlegroups.com...
>
> >> >Such as a 200 DB cmos imager
> >> But will average people readilly accept a liquid helium cooled camera?
> :-)
> >I would, as would anyone looking for brown dwarfs.
>
> Just as I said, highly specialised fields only. Lets not confuse it with
> general photography however.
>
> >Trust me, sufficient DR of cmos imagers exist as is, and it isn't even
> >all that spendy.
>
> I suggest you find out what is actually necessary to produce a 200dB range
> of output from such a sensor!
> I can't see it happening anytime soon. Multiple scan is the accepted
> practical method of obtaining such a range.
> But do let us know when you actually purchase an imager with a single pass
> 200dB range :-)
>
> MrT.
200 db image sensors are already off the shelf, and using a dual 16
bit ADC doesn't seem so terribly spendy or complex. Even liquid
helium or more likely stacked thermoelectric Peltier cooling isn't all
that insurmountable for extending the cmos or ccd peak sensitivity
into the near IR range.
Camera firmware and/or software already offers up to 256 scans per
image.
~ BG
Mr.T
>> I suggest you find out what is actually necessary to produce a 200dB
range
>> of output from such a sensor!
>> I can't see it happening anytime soon. Multiple scan is the accepted
>> practical method of obtaining such a range.
>> But do let us know when you actually purchase an imager with a single
pass
>> 200dB range :-)
>200 db image sensors are already off the shelf,
I said "single pass", as you have been saying all along.
If you don't really mean single pass, then you in fact agree "multiple scan
is the accepted practical method of obtaining such a range." and we can stop
all the arguing.
>Even liquid helium or more likely stacked thermoelectric Peltier cooling
>isn't all that insurmountable
Do calculate the necessary voltages for a 200dB analog signal, even when
operating close to absolute zero and thus theoretical noise limits, let
alone what you can achieve with a simple Peltier cooler!
>Camera firmware and/or software already offers up to 256 scans per
>image.
Exactly, so stop confusing the issue with spurious claims. With 256 scans
the whole issue of ADC's you brought up is irrelevant. Each scan is less
than 16 bits anyway. Problem solved, just do it! :-)
MrT.
Mark F
>
> "BradGuth" <brad...@gmail.com> wrote in message
> news:64c02205-b5f0-4582...@f40g2000pri.googlegroups.com...
> >> I suggest you find out what is actually necessary to produce a 200dB
> range
> >> of output from such a sensor!
> >> I can't see it happening anytime soon. Multiple scan is the accepted
> >> practical method of obtaining such a range.
> >> But do let us know when you actually purchase an imager with a single
> pass
> >> 200dB range :-)
>
> >200 db image sensors are already off the shelf,
>
> I said "single pass", as you have been saying all along.
> If you don't really mean single pass, then you in fact agree "multiple scan
> is the accepted practical method of obtaining such a range." and we can stop
> all the arguing.
>
>
> >Even liquid helium or more likely stacked thermoelectric Peltier cooling
> >isn't all that insurmountable
Assume that all of the problems with dynamic range and sensor noise
have been handled:
1. What signal to noise ratio could be expected from the sensor?
2. What signal to noise ratio could be expected in the optical system?
My guess is that there would still need to be additional processing
done to get rid of the scattered light from the bright parts of the
system that falls on the sensors in the "dark" areas. Therefore more
processing still is needed even if there is an infinite dynamic range
and infinite signal to noise ratio from the sensor itself. Any
real sensor, even with 150 bits (450 db) dynamic range and 96 bits
(300 db) signal to noise ratio, limit what can be done to improve the
signal to noise ratio improvement that can be done to the data from
the optical system.
BradGuth
> On Wed, 4 Feb 2009 13:40:50 +1100, "Mr.T" <MrT@home> wrote:
>
A sufficiently narrow bandpass optical filter would exclude the vast
bulk of other stellar illumination, plus firmware and later software
processing should be capable of either identifying and/or excluding
all but Sirius C.
I didn't say it would be exactly cheap or easy. Just a good 10000x
optical lens or set of mirrors would be in of itself spendy.
~ BG
BradGuth
> "BradGuth" <bradg...@gmail.com> wrote in message
Good to hear that I'm not half as crazy as I've frequently been
informed.
~ BG
Mr.T
"Mark F" <mark...@gmail.com> wrote in message
news:j5rjo4pjucgusc8bk...@4ax.com...
> My guess
And that's all your claims are unfortunately.
> Any real sensor, even with 150 bits (450 db) dynamic range
> and 96 bits (300 db) signal to noise ratio,
Once again you have NO idea what you are saying, so why do you bother?
The practical limits of our universe don't seem to apply to yours, nor do
normally accepted definitions it seems.
MrT.
Mr.T
"Mr.T" <MrT@home> wrote in message
news:498a4440$0$7704$afc3...@news.optusnet.com.au...
> > and 96 bits (300 db) signal to noise ratio,
>
> Once again you have NO idea what you are saying, so why do you bother?
> The practical limits of our universe don't seem to apply to yours, nor do
> normally accepted definitions it seems.
Oops, my apologies for confusing you with BG. I do hope those *stupid*
figures weren't serious however.
MrT.
BradGuth
> "Mr.T" <MrT@home> wrote in message
>
> news:498a4440$0$7704$afc3...@news.optusnet.com.au...
>
> >news:j5rjo4pjucgusc8bk...@4ax.com...
> > > Any real sensor, even with 150 bits (450 db) dynamic range
> > > and 96 bits (300 db) signal to noise ratio,
>
> > Once again you have NO idea what you are saying, so why do you bother?
> > The practical limits of our universe don't seem to apply to yours, nor do
> > normally accepted definitions it seems.
>
> Oops, my apologies for confusing you with BG. I do hope those *stupid*
> figures weren't serious however.
>
> MrT.
What exactly do you have against utilizing terrific dynamic range and
bandpass optical filters?
~ BG
Mr.T
>> > > and 96 bits (300 db) signal to noise ratio,
>
>bandpass optical filters?
Nothing, I do like to keep discussions to what is physically possible in
this universe however.
And the maths could at least be correct.
MrT.
BradGuth
> "BradGuth" <bradg...@gmail.com> wrote in message
In that case a 200 DR imager and as much ADC plus quality optics that
you and I can afford is technically doable. After all, we're talking
about imaging a very nearby exoplanet with moons the size of Earth.
Even the 100 DR imager with a 16 bit ADC shouldn't be all that far
from the nearest Walmart.
~ BG