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S/N figures etc for digital cameras

S/N figures etc for digital cameras

2004-02-28 by Steve Kale

Does anyone know where I can take a look at key performance stats for several digital 
cameras?  I am keen to compare the Canon 1Ds and 1D MK II against Leaf and PhaseOne 
digital backs.  I know these are completely different solutions but a I struggle with 
understanding the price gap.  If one extrapolates the 1D MK II pixel count up to a full 
frame 35mm hopefully-to-be-announced-in-the-not-so-distant-future 1Ds MK II then it 
could be around 16-17 megapixels which really becomes very interesting.  I understand 
the Canon is 12 bit vs 16 bit for the higher order digital backs (but then not so long ago 
we did almost everything in 8 bit.....).  So I assume the signal to noise ratio is where the 
battle is.  (I can process the RAW data of either a Canon or PhaseOne in CaptureOne and 
so that is an even platform.)  I just took a look at the portrait shots on Canon's website 
from the 1Ds and did not think these were particularly sharp vs shots from a 6mp 
PhaseOne back I have used.  What other key factors should I be looking at?  (please ignore 
portability, handling ease, fps etc  -  just image quality.)

Thanks

Steve

Re: [Digital BW] S/N figures etc for digital cameras

2004-02-29 by Tom Baker

Did you download and print those images from the Canon site?  They make pretty impressive prints, even in b&w.  I'm not a Canon owner, but I sure liked what I saw in the prints.  And, I printed 4x the native image size.
 
Tom Baker

Steve Kale <stevekale@...> wrote:
Does anyone know where I can take a look at key performance stats for several digital 
cameras?  I am keen to compare the Canon 1Ds and 1D MK II against Leaf and PhaseOne 
digital backs.  I know these are completely different solutions but a I struggle with 
understanding the price gap.  If one extrapolates the 1D MK II pixel count up to a full 
frame 35mm hopefully-to-be-announced-in-the-not-so-distant-future 1Ds MK II then it 
could be around 16-17 megapixels which really becomes very interesting.  I understand 
the Canon is 12 bit vs 16 bit for the higher order digital backs (but then not so long ago 
we did almost everything in 8 bit.....).  So I assume the signal to noise ratio is where the 
battle is.  (I can process the RAW data of either a Canon or PhaseOne in CaptureOne and 
so that is an even platform.)  I just took a look at the portrait shots on Canon's website 
from the 1Ds and did not think these were particularly sharp vs shots from a 6mp 
PhaseOne back I have used.  What other key factors should I be looking at?  (please ignore 
portability, handling ease, fps etc  -  just image quality.)

Thanks

Steve



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[Non-text portions of this message have been removed]

Re: [Digital BW] S/N figures etc for digital cameras

2004-02-29 by Steve Kale

Hi Tom

I must admit I did not print them but rather brought them into PS CS and
took a look at them there.  I have being doing quite a bit of work with a
friend's PhaseOne back and the Canon images at a quick review were not in
the same league.  Of course I would love to have my own Leaf or PhaseOne but
they are out of my price range for now.  Hence my salivating at the prospect
of a MK II 1Ds which with a push and a shove I might convince myself I need
it for Xmas  :-)  But a look at the 1D MK II images made me step back a
little.

Steve
Show quoted textHide quoted text
> From: Tom Baker <tbaker1328@...>
> Reply-To: DigitalBlackandWhiteThePrint@yahoogroups.com
> Date: Sat, 28 Feb 2004 18:59:56 -0800 (PST)
> To: DigitalBlackandWhiteThePrint@yahoogroups.com
> Subject: Re: [Digital BW] S/N figures etc for digital cameras
> 
> Did you download and print those images from the Canon site?  They make pretty
> impressive prints, even in b&w.  I'm not a Canon owner, but I sure liked what
> I saw in the prints.  And, I printed 4x the native image size.
> 
> Tom Baker

RE: [Digital BW] S/N figures etc for digital cameras

2004-02-29 by Julian Doncaster (FastMail)

Tom
> Of course I would love to have my own Leaf or
> PhaseOne but
> they are out of my price range for now.  Hence my salivating at
> the prospect
> of a MK II 1Ds which with a push and a shove I might convince
> myself I need
> it for Xmas  :-)  But a look at the 1D MK II images made me step back a
>
I thought that a Mk II Canon 1Ds had a less advanced sensor than the 1D, as
it is aimed a different market.

Julian

Re: [Digital BW] S/N figures etc for digital cameras

2004-02-29 by Truman Prevatt

The noise is electrical noise. Every electrical circuit has noise - it 
is a results of random motion of electrons. The power of that noise is 
proportional to the temperature and something called "bandwidth." In 
fact there is a ever present electrical back ground noise on the earth 
of about 10^-15 watts. The only way to avoid electrical noise is to cool 
the circuit to absolute zero where it would be a little uncomfortable to 
take pictures and the shutter wouldn't work.

How this impact the image is when the sensors that count photons are 
characterized by the electronics (there is some photon noise but 
electrical noise is by far the limiting factor). The S/N (signal to 
noise ratio)  is the measure of the signal power -" number of photons" 
vs. electrical noise background in the circuit. The reason there is 
higher noise at higher ISO is the signals are amplified prior to the 
analogue to digital conversion to bring the voltage into the range of 
the A/D so another type of noise won't be a problem (quantization 
noise).  The amplification amplifies the noise along with the signal.

The 12 bit A/D will perform better than the 8 bit mostly because there 
is more margin in the dynamic range. It is unclear if 16 is needed but 
the more bits the better. I have seen RF sensor system where 24 bits 
were required.  One way to get better S/N is with "bigger" sensors (more 
are at each sensor location)  in the array that count more photons in a 
fixed shutter time vs. a small sensor. You don't eliminate the noise but 
provide a bigger signal to the A/D for a higher S/N. That's why the new 
Sony F585 is so noisy compared to the DSLR out there. However to get 
bigger sensor at each location you need a bigger array - the bigger the 
array the more expensive it is to produce ( cost will go up with area).

The noise in a Canon, Nikon, etc. is going to "look different" than in 
the Sigma because of the interpolation. The noise that exist in nature 
is what is called "white" that is there is no correlation between 
neighboring pixels. Because of the interpolation to get a full number of 
pixels in the mosaic sensors the noise is correlated in neighboring 
pixels. See  http://www.dpreview.com/reviews/sigmasd9/page15.asp where 
this is shown and is pretty clear what is going on.

Dpreview has pretty good reviews of digital cameras, http://www.dpreview.com

Truman
Show quoted textHide quoted text
>
>
>Steve Kale <stevekale@...> wrote:
>Does anyone know where I can take a look at key performance stats for several digital 
>cameras?  I am keen to compare the Canon 1Ds and 1D MK II against Leaf and PhaseOne 
>digital backs.  I know these are completely different solutions but a I struggle with 
>understanding the price gap.  If one extrapolates the 1D MK II pixel count up to a full 
>frame 35mm hopefully-to-be-announced-in-the-not-so-distant-future 1Ds MK II then it 
>could be around 16-17 megapixels which really becomes very interesting.  I understand 
>the Canon is 12 bit vs 16 bit for the higher order digital backs (but then not so long ago 
>we did almost everything in 8 bit.....).  So I assume the signal to noise ratio is where the 
>battle is.  (I can process the RAW data of either a Canon or PhaseOne in CaptureOne and 
>so that is an even platform.)  I just took a look at the portrait shots on Canon's website 
>from the 1Ds and did not think these were particularly sharp vs shots from a 6mp 
>PhaseOne back I have used.  What other key factors should I be looking at?  (please ignore 
>portability, handling ease, fps etc  -  just image quality.)
>
>Thanks
>
>Steve
>
>  
>

Re: [Digital BW] S/N figures etc for digital cameras

2004-02-29 by Steve Kale

Truman

Thanks for the reply and the references.  But have you seen any reviews of
the high end digital SLRs vs digital backs?  It seems like these two markets
are kept well apart.  I suspect the 35mm guys simply don¹t yet want to rate
their product against the 1 shot per second backs¹ quality and are focused
on their own closer-to-home competition.  I fear the MF guys see no need to
make the comparison or display the stats because it could undermine the
significant premium they can extract from studio photographers that want to
stay looking studio-pro rather than sports-pro/prosumer.  If a PhaseOne H10
uses a 35mm-sized mosaic sensor like the 1 Ds (albeit one is CCD and the
other CMOS) how much noise cuts the price in half (even ignoring all the
other benefits of faster fps and portability)?  Ask a dealer of both why
there is such a difference in price and he will say that the PhaseOne/Leaf
delivers a much better image, lower noise etc.  But no one I have spoken too
is able to tell me the noise stats.  Canon brags about the high signal to
noise ratio of the new MK II.  Yet I can't find that stat on their website.
16 megapixels at a decent price (let alone the other features) becomes a
powerful proposition vs film if the image quality is close to that which I
have seen from an old 6 mp H10.  Like I said, how much noise cuts the price
in half?

Steve
Show quoted textHide quoted text
From: Truman Prevatt <tprevatt@...>
Reply-To: DigitalBlackandWhiteThePrint@yahoogroups.com
Date: Sun, 29 Feb 2004 09:03:42 -0500
To: DigitalBlackandWhiteThePrint@yahoogroups.com
Subject: Re: [Digital BW] S/N figures etc for digital cameras

The noise is electrical noise. Every electrical circuit has noise - it
is a results of random motion of electrons. The power of that noise is
proportional to the temperature and something called "bandwidth." In
fact there is a ever present electrical back ground noise on the earth
of about 10^-15 watts. The only way to avoid electrical noise is to cool
the circuit to absolute zero where it would be a little uncomfortable to
take pictures and the shutter wouldn't work.

How this impact the image is when the sensors that count photons are
characterized by the electronics (there is some photon noise but
electrical noise is by far the limiting factor). The S/N (signal to
noise ratio)  is the measure of the signal power -" number of photons"
vs. electrical noise background in the circuit. The reason there is
higher noise at higher ISO is the signals are amplified prior to the
analogue to digital conversion to bring the voltage into the range of
the A/D so another type of noise won't be a problem (quantization
noise).  The amplification amplifies the noise along with the signal.

The 12 bit A/D will perform better than the 8 bit mostly because there
is more margin in the dynamic range. It is unclear if 16 is needed but
the more bits the better. I have seen RF sensor system where 24 bits
were required.  One way to get better S/N is with "bigger" sensors (more
are at each sensor location)  in the array that count more photons in a
fixed shutter time vs. a small sensor. You don't eliminate the noise but
provide a bigger signal to the A/D for a higher S/N. That's why the new
Sony F585 is so noisy compared to the DSLR out there. However to get
bigger sensor at each location you need a bigger array - the bigger the
array the more expensive it is to produce ( cost will go up with area).

The noise in a Canon, Nikon, etc. is going to "look different" than in
the Sigma because of the interpolation. The noise that exist in nature
is what is called "white" that is there is no correlation between
neighboring pixels. Because of the interpolation to get a full number of
pixels in the mosaic sensors the noise is correlated in neighboring
pixels. See  http://www.dpreview.com/reviews/sigmasd9/page15.asp where
this is shown and is pretty clear what is going on.

Dpreview has pretty good reviews of digital cameras, http://www.dpreview.com

Truman




[Non-text portions of this message have been removed]

Re: [Digital BW] S/N figures etc for digital cameras

2004-02-29 by Steve Kale

The new 1D MK II has a smaller sensor than the 1 Ds (in size) but a higher
density of pixels.  Yes it is aimed at a different market ­ those who need
8.5 fps vs 3.   Presumably the next step for Canon will be to take the
higher density chip and enlarge it to full frame 35mm and release a MK II
1Ds (sounds simple doesn¹t it....).

<I thought that a Mk II Canon 1Ds had a less advanced sensor than the 1D, as
it is aimed a different market.

Julian>





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[Non-text portions of this message have been removed]

Re: [Digital BW] S/N figures etc for digital cameras

2004-02-29 by Truman Prevatt

Steve,

That is the 64 dollar question. The answer is it probably depends on who 
is looking at the image. I could take a CD cut add noise to it to 
simulate 8 bit quatization (a CD is 16 bits) and play the original and 
the one with noise back to back to my wife and she would not be able to 
tell the difference - but I sure can.

So there are two questions here - the one is technical the other is one 
of based ot the expectations of the individual. But you are right I've 
never seen a full up review of the digital backs like the ones you see 
on DPreview of DSLR's and prosumer digitals. On the other hand at 20 
grand a pop there is probably not a lot of demand either to justify the 
expense of the review.

Clearly at some point the nosie is so low that it is not noticable. 
Currently we may not know that threshold.  In reconnoissance systems 
there are "rules of thumb" but they are based on the ability of 
automatic target recognition systems to perform rather than to please 
the eye and the eye can detect a lot of noise in images that these 
target  recognizes work just fine.

I would be interesting to know these numbers. Otherwise the digital 
world is going to be based the hype of big pixel numbers and big S/N 
numbers.

Truman


Steve Kale wrote:

> Truman
>
> Thanks for the reply and the references.  But have you seen any reviews of
> the high end digital SLRs vs digital backs?  It seems like these two 
> markets
> are kept well apart.  I suspect the 35mm guys simply don¹t yet want to 
> rate
> their product against the 1 shot per second backs¹ quality and are focused
> on their own closer-to-home competition.  I fear the MF guys see no 
> need to
> make the comparison or display the stats because it could undermine the
> significant premium they can extract from studio photographers that 
> want to
> stay looking studio-pro rather than sports-pro/prosumer.  If a 
> PhaseOne H10
> uses a 35mm-sized mosaic sensor like the 1 Ds (albeit one is CCD and the
> other CMOS) how much noise cuts the price in half (even ignoring all the
> other benefits of faster fps and portability)?  Ask a dealer of both why
> there is such a difference in price and he will say that the PhaseOne/Leaf
> delivers a much better image, lower noise etc.  But no one I have 
> spoken too
> is able to tell me the noise stats.  Canon brags about the high signal to
> noise ratio of the new MK II.  Yet I can't find that stat on their 
> website.
> 16 megapixels at a decent price (let alone the other features) becomes a
> powerful proposition vs film if the image quality is close to that which I
> have seen from an old 6 mp H10.  Like I said, how much noise cuts the 
> price
> in half?
>
> Steve
>


[Non-text portions of this message have been removed]

RE: [Digital BW] S/N figures etc for digital cameras

2004-03-01 by Paul D. DeRocco

> From: Truman Prevatt [mailto:tprevatt@...]
>
> So there are two questions here - the one is technical the other is one
> of based ot the expectations of the individual. But you are right I've
> never seen a full up review of the digital backs like the ones you see
> on DPreview of DSLR's and prosumer digitals. On the other hand at 20
> grand a pop there is probably not a lot of demand either to justify the
> expense of the review.
>
> Clearly at some point the nosie is so low that it is not noticable.
> Currently we may not know that threshold.  In reconnoissance systems
> there are "rules of thumb" but they are based on the ability of
> automatic target recognition systems to perform rather than to please
> the eye and the eye can detect a lot of noise in images that these
> target  recognizes work just fine.
>
> I would be interesting to know these numbers. Otherwise the digital
> world is going to be based the hype of big pixel numbers and big S/N
> numbers.

I actually ran some rigorous tests on my Minolta DiMage 7. Since its raw
output is uncompressed, I was able to write a program that rounded it off to
fewer than the 12 bits that the camera produces. On a test shot of blue sky,
I found that I had to reduce to 8 bits in order to see any difference after
applying a drastic curve, and even then I couldn't see any actual banding.
My conclusion was that with that noisy CCD, the extra four bits of raw mode
data were complete rubbish.

My Canon 10D has nearly two bits better S/N, based on comparing results at
various ISO settings. This means that a 10-bit converter would be enough,
although 12 bits isn't a significant extra expense. I've never used a
scanning back, or seen any tested, but I see no reason why they couldn't
perform as well as a good CCD film scanner, which is probably around 12
bits.

Of course, the only reasons for needing more S/N is so that you can shoot in
very low light, or shoot very contrasty subjects and pull detail out of the
muck. I suspect scanning backs are intended to be used in the studio, where
one has control over the lighting, so don't even really need an enormous
dynamic range. Their primary design goal is just to get huge numbers of
pixels. The _really_ quiet sensors are used in astrophotography.

--

Ciao,               Paul D. DeRocco
Paul                mailto:pderocco@...

Re: [Digital BW] S/N figures etc for digital cameras

2004-03-01 by Truman Prevatt

One reason to have more bits in the A/D is to give yourself a margin for 
error in an image for under or over exposure or in RF systems for bad 
gain settings. So there are two issues, the S/N required and the dynamic 
range that insures that S/N is still captured even in the case of a 
screw up.

Truman

Paul D. DeRocco wrote:

> >
> I actually ran some rigorous tests on my Minolta DiMage 7. Since its raw
> output is uncompressed, I was able to write a program that rounded it 
> off to
> fewer than the 12 bits that the camera produces. On a test shot of 
> blue sky,
> I found that I had to reduce to 8 bits in order to see any difference 
> after
> applying a drastic curve, and even then I couldn't see any actual banding.
> My conclusion was that with that noisy CCD, the extra four bits of raw 
> mode
> data were complete rubbish.
>
> My Canon 10D has nearly two bits better S/N, based on comparing results at
> various ISO settings. This means that a 10-bit converter would be enough,
> although 12 bits isn't a significant extra expense. I've never used a
> scanning back, or seen any tested, but I see no reason why they couldn't
> perform as well as a good CCD film scanner, which is probably around 12
> bits.
>
> Of course, the only reasons for needing more S/N is so that you can 
> shoot in
> very low light, or shoot very contrasty subjects and pull detail out 
> of the
> muck. I suspect scanning backs are intended to be used in the studio, 
> where
> one has control over the lighting, so don't even really need an enormous
> dynamic range. Their primary design goal is just to get huge numbers of
> pixels. The _really_ quiet sensors are used in astrophotography.
>
> --
>
> Ciao,               Paul D. DeRocco
> Paul                mailto:pderocco@...
>
>


[Non-text portions of this message have been removed]

RE: [Digital BW] S/N figures etc for digital cameras

2004-03-01 by Paul D. DeRocco

> From: Truman Prevatt [mailto:tprevatt@...]
>
> One reason to have more bits in the A/D is to give yourself a margin for
> error in an image for under or over exposure or in RF systems for bad
> gain settings. So there are two issues, the S/N required and the dynamic
> range that insures that S/N is still captured even in the case of a
> screw up.

That's a good reason to want more S/N in the system, not just more bits in
the A/D. There's never any reason to have more bits in the A/D than the S/N
justifies, because any extra bits will be garbage.

--

Ciao,               Paul D. DeRocco
Paul                mailto:pderocco@...

Re: [Digital BW] S/N figures etc for digital cameras

2004-03-01 by Truman Prevatt

An A/D takes a fixed voltage range say 0 to 1 volt. The signal needs to 
be in that range in order for the A/D to provide the a digital 
conversion that maintains the SNR.  For example if you clip you will not 
only have artifacts you will lose some SNR. Same thing if the input 
voltage out of the sensor is to small.

If the A/D is designed with with the same SNR expected out of the sensor 
electronics then as long as everything is correct, i.e. the exposure is 
perfect. On the other hand if it is under or over exposed the resulting 
SNR out of the A/D will be less than the input SNR. An 8 bit A/D will 
produce a 36 dB SNR signal for an infinite input SNR signal 
(quantization noise). A 12 bit has 60 dB and a 10 bit 48 dB. If you have 
48 dB coming out of the camera electronics the output of the A/D is 
limited by the A/D quantization noise so 8 bits are not sufficient. If 
the exposure is perfectly set so the input voltage to the A/D is 0 to 1 
volt 10 bits will be sufficient. However, if it is one stop 
underexposed, the top bit won't be used hence the resulting output SNR 
of the A/D is 45 dB - hence there is a loss of SNR. If a 12 bit A/D is 
uesd the output signal will sitllb e 48 dB because of the extra bits (11 
bits would be used).

So have enough bits for some margin is not a bad idea. If the most 
significant bits are not used - they can be thrown away. Most likely the 
image will be scaled to max range in processing and with the extra bits 
that will not be a problem. I suspect that in practice 12 bits is 
sufficient for digital photography - and it gives you a comfortable margin.

Truman



Paul D. DeRocco wrote:

> > From: Truman Prevatt [mailto:tprevatt@...]
> >
> > One reason to have more bits in the A/D is to give yourself a margin for
> > error in an image for under or over exposure or in RF systems for bad
> > gain settings. So there are two issues, the S/N required and the dynamic
> > range that insures that S/N is still captured even in the case of a
> > screw up.
>
> That's a good reason to want more S/N in the system, not just more bits in
> the A/D. There's never any reason to have more bits in the A/D than 
> the S/N
> justifies, because any extra bits will be garbage.
>
> --
>
> Ciao,               Paul D. DeRocco
> Paul                mailto:pderocco@...
>
>


[Non-text portions of this message have been removed]

Re: [Digital BW] S/N figures etc for digital cameras

2004-03-01 by Tom Baker

We don't really have to go by either noise or pixel count numbers.  Look at the prints side by side.  In the couple of instances I've been able to do that, there was no question which produced the better image.  At $20,000+ there should be a difference.  But, remember, those two systems are desigen for different purposes.  So, this is really an apples to oranges comparison.
 
Tom Baker

Truman Prevatt <tprevatt@...> wrote:
Steve,

That is the 64 dollar question. The answer is it probably depends on who 
is looking at the image. I could take a CD cut add noise to it to 
simulate 8 bit quatization (a CD is 16 bits) and play the original and 
the one with noise back to back to my wife and she would not be able to 
tell the difference - but I sure can.

So there are two questions here - the one is technical the other is one 
of based ot the expectations of the individual. But you are right I've 
never seen a full up review of the digital backs like the ones you see 
on DPreview of DSLR's and prosumer digitals. On the other hand at 20 
grand a pop there is probably not a lot of demand either to justify the 
expense of the review.

Clearly at some point the nosie is so low that it is not noticable. 
Currently we may not know that threshold.  In reconnoissance systems 
there are "rules of thumb" but they are based on the ability of 
automatic target recognition systems to perform rather than to please 
the eye and the eye can detect a lot of noise in images that these 
target  recognizes work just fine.

I would be interesting to know these numbers. Otherwise the digital 
world is going to be based the hype of big pixel numbers and big S/N 
numbers.

Truman


Steve Kale wrote:

> Truman
>
> Thanks for the reply and the references.  But have you seen any reviews of
> the high end digital SLRs vs digital backs?  It seems like these two 
> markets
> are kept well apart.  I suspect the 35mm guys simply don�t yet want to 
> rate
> their product against the 1 shot per second backs� quality and are focused
> on their own closer-to-home competition.  I fear the MF guys see no 
> need to
> make the comparison or display the stats because it could undermine the
> significant premium they can extract from studio photographers that 
> want to
> stay looking studio-pro rather than sports-pro/prosumer.  If a 
> PhaseOne H10
> uses a 35mm-sized mosaic sensor like the 1 Ds (albeit one is CCD and the
> other CMOS) how much noise cuts the price in half (even ignoring all the
> other benefits of faster fps and portability)?  Ask a dealer of both why
> there is such a difference in price and he will say that the PhaseOne/Leaf
> delivers a much better image, lower noise etc.  But no one I have 
> spoken too
> is able to tell me the noise stats.  Canon brags about the high signal to
> noise ratio of the new MK II.  Yet I can't find that stat on their 
> website.
> 16 megapixels at a decent price (let alone the other features) becomes a
> powerful proposition vs film if the image quality is close to that which I
> have seen from an old 6 mp H10.  Like I said, how much noise cuts the 
> price
> in half?
>
> Steve
>


[Non-text portions of this message have been removed]



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Re: [Digital BW] S/N figures etc for digital cameras

2004-03-01 by Steve Kale

Hi Tom

A couple of quick comments.  Firstly price is not necessarily a good of
judge of quality and value.  Secondly, yes they are designed - at the moment
- for two different purposes but watch them converge.  In the last few years
we have seen 645 photography pick up more and more of the features of 35mm
(autofocus etc) as photographers wanted to gain a broader use of the larger
film size.  In many cases I suspect that the level of convergence has been
slowed by the key limiting factor of having to wind forward larger film -
issues that don't exist with digital.  I don't think we are too far away
from someone like Mamiya producing an digital-only 645 - watch the
collaboration and bundling with the digital back guys.  Note the ISO
expansion of the digital backs, for example.  Also, the digital backs (I am
not referring to the scan backs) are also having to go portable - the new P
series from PhaseOne is a good example.  In a digital world it is far easier
for these products to converge with regard to function.  Of course there
will always be compromises made to tailor to a particular activity and
Canon's breaking of its 1x line into the 1Ds and the 1D is a very good
example.  But I really do see the 1Ds targeted as an alternative to the
lower end, 35mm sized sensor, 645 backs and that these particular digital
backs will not be able to hold their pricing.   (Many pros are recommending
a newcomer to digital purchase a 1Ds rather than an 11mp digital back as a
much more versatile first digital camera.)  That's why my question was
specific to a comparison of the likes of a 1Ds or 1D MK II versus a 35mm
sized sensor digital back.  FPS and portability features are easy to
compare.  Image quality is not.  It seems this comparison is a very murky
one - even on a single variable such as S/N.

Now a full-framed 645 portable digital back with a pixel density like the 1D
MK II (I wonder what the pixel count would be if did the extrapolation?)
would be sweet but yes will likely be a very expensive proposition....but
the challenge is being laid down by the 35mm SLR kings and not the 645 guys.

:-)

<At $20,000+ there should be a difference.  But, remember, those two systems
are desigen for different purposes.  So, this is really an apples to oranges
comparison.
> 
> Tom Baker>

Re: [Digital BW] S/N figures etc for digital cameras

2004-03-01 by Tom Baker

Yep.  That's all in the future.
 
Tom Baker

Steve Kale <stevekale@btinternet.com> wrote:
Hi Tom

A couple of quick comments.  Firstly price is not necessarily a good of
judge of quality and value.  Secondly, yes they are designed - at the moment
- for two different purposes but watch them converge.  In the last few years
we have seen 645 photography pick up more and more of the features of 35mm
(autofocus etc) as photographers wanted to gain a broader use of the larger
film size.  In many cases I suspect that the level of convergence has been
slowed by the key limiting factor of having to wind forward larger film -
issues that don't exist with digital.  I don't think we are too far away
from someone like Mamiya producing an digital-only 645 - watch the
collaboration and bundling with the digital back guys.  Note the ISO
expansion of the digital backs, for example.  Also, the digital backs (I am
not referring to the scan backs) are also having to go portable - the new P
series from PhaseOne is a good example.  In a digital world it is far easier
for these products to converge with regard to function.  Of course there
will always be compromises made to tailor to a particular activity and
Canon's breaking of its 1x line into the 1Ds and the 1D is a very good
example.  But I really do see the 1Ds targeted as an alternative to the
lower end, 35mm sized sensor, 645 backs and that these particular digital
backs will not be able to hold their pricing.   (Many pros are recommending
a newcomer to digital purchase a 1Ds rather than an 11mp digital back as a
much more versatile first digital camera.)  That's why my question was
specific to a comparison of the likes of a 1Ds or 1D MK II versus a 35mm
sized sensor digital back.  FPS and portability features are easy to
compare.  Image quality is not.  It seems this comparison is a very murky
one - even on a single variable such as S/N.

Now a full-framed 645 portable digital back with a pixel density like the 1D
MK II (I wonder what the pixel count would be if did the extrapolation?)
would be sweet but yes will likely be a very expensive proposition....but
the challenge is being laid down by the 35mm SLR kings and not the 645 guys.

:-)

<At $20,000+ there should be a difference.  But, remember, those two systems
are desigen for different purposes.  So, this is really an apples to oranges
comparison.
> 
> Tom Baker>



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