Diffraction limit and D2x

I don't understand this. What does sensor size have to do with DOF?
At a given aperture, DOF is a function of distance from the subject. The closer the subject, the less DOF; the farther away from the subject, the greater the DOF. The crop factor of the APS sensor requires greater distance from the subject for the same FOV as a larger sensor, and therefore you end up with more DOF at the same aperture than a larger sensor due to that increased distance from the subject.

-Mark
 
it simply isn't needed by anyone that knows what they are doing (there I said it) or who isn't shooting very very special niche applications.

Now that Nikon has shown that in one bold leap into CMOS sensors they could deliver class leading performance (at least at low ISO values) in a high density APS - C framed body, it's time to improve the quality of the pixels at highier ISO. Though the performance at low ISO's is as good as the best, that performance falls quickly with increased ISO levels. As well detail rendition (effective resolution) degrades as the heavy noise compression kicks in making it not even close to being the best high ISO shooter. Nikon needs IMO, to focus on making the same density chip more sensitive at highier ISO values, shrink the component size per photosite in the next generation, increase the photoreceptive area, refine the image processing pipeline, remove the need for noise reduction so that a standard ISO range of 100 - 1600 is the norm. The 12mp of the D2x is enough to provide 300dpi prints at 10 x 14, more than enough to keep the majority of pro shooters happy (again, if they know what they are doing)...it's time as consumers that we demand quality instead of quantity.

We already see in the comparisons between the D2x and the Canon 1dsII that the additional 4mp contributes little to extra detail rendition above the D2x (especially after accounting for differences in focal length and fov due to the multiplier on the D2x) or the previous 1Ds.

Here's to a Nikon CMOS gen 2 chip being the same 12mp but with significantly improved performance at highier ISO values.

Of course I realize this is pretty much a pipe dream, as marketing will ensure that mp continues to drive development choices but it's sad that even at the pro level the ignorant quest for more mp mindless of the drawbacks will lead to eventually to the same slow drop in quality at highier ISO values over time as occured with prosumers as they went from 5mp to 8mp.

Regards,
Wayne
Yes, it would appear that Nikon is nearing the limit of the APS
sized sensor with the D2X. Since the smaller sensor has greater
depth of field, one doesn't have to stop down as much but noise is
still a problem.
Not really. I'm not at all sure there is any fundamental agreement
on what a reasonable limite would be. If a person is OK with
taking a most of their images at relatively larger apertures, there
is plenty of room for more pixel density. Especially if the images
are generally taken in good light which means that they can use a
lower ISO and avoid the noise with tends to appear with smaller
sensor sites. And if you choose to stop down for increased DOF you
simply lose some resolution that you wouldn't otherwise have anyway
with a lower resolution sensor.

--
Jay Turberville
http://www.jayandwanda.com
--

 
to cater to that elitist group?
What makes a person wanting higher resolution elitist?
The same group that USED Ektar25,
Kodachrome25, Agfapan25 and Technical PAN in film cameras. Get my
drift?
Yeah. That was me. I used technical pan and rolled my own developer. I also shot a lot of Kodachrome. High ISO and large grain never appealed to me.
APS is close to the end as far as resolution is concerned.
Define close. My take is that we will see APS DSLRs reach around 24Mp. That is still a larger pixel pitch than a CP995 or CP5000. These cameras may not be the most common and they will probably be specialty cameras - or perhaps elitist cameras if I take your apparent point of view.

A great setup would be an X3 type sensor where the camera could gang pixels in groups of four to halve the resolution for shots where larger sensor cells and lower resolution would be preferred. This would actually be a 15Mp sensor count camera but it would have the resolution of a 25Mp bayer mask camera. In either case, the lens would have to resolve around 125 lp/mm. I'm not sure how hard that will be to accomplish.

--
Jay Turberville
http://www.jayandwanda.com
 
Jay,

I have to agree with Wayne here. There is no general consensus regarding resolution and ISO performance since any reasonable photographer chooses a camera to fit his/her shooting needs.

The D2X would be fine for landscape and architectural work, but it would not be the tool of choice for available light sports photogtraphy, where the Canon EOS 1D Mark II would be preferable.

Ektar 25 was a great film, but you could always drop something faster into the camera when needed. Most of us can't afford to have 2 or more digital SRLs, so we want a reasonable tradeoff between resolution and ISO performance.

I think one of the things that killed the Kodak full frame digital was its poor high ISO performance.

--
Bill Janes
Wayne
Yes, it would appear that Nikon is nearing the limit of the APS
sized sensor with the D2X. Since the smaller sensor has greater
depth of field, one doesn't have to stop down as much but noise is
still a problem.
Not really. I'm not at all sure there is any fundamental agreement
on what a reasonable limite would be. If a person is OK with
taking a most of their images at relatively larger apertures, there
is plenty of room for more pixel density. Especially if the images
are generally taken in good light which means that they can use a
lower ISO and avoid the noise with tends to appear with smaller
sensor sites. And if you choose to stop down for increased DOF you
simply lose some resolution that you wouldn't otherwise have anyway
with a lower resolution sensor.

--
Jay Turberville
http://www.jayandwanda.com
 
APS is close to the end as far as resolution is concerned.
Define close. My take is that we will see APS DSLRs reach around
24Mp. That is still a larger pixel pitch than a CP995 or CP5000.
These cameras may not be the most common and they will probably be
specialty cameras - or perhaps elitist cameras if I take your
apparent point of view.
and be restricted to an ISO cap of 200 or lower just like those prosumer digitals. Will such a low range , hgh mp body be profitable for the manufacturers to devote R&D and marketing to??? It should be clear that the more generally useful body (read: larger ISO range at optimal pixel count) will sell the most and offer a better cost / profit ratio for the manufacturer than making a body with restricted applications that will sell at very low volume. I am sure if the market is out there the manufacturers will cater to it, but it sure isn't going to be cheap for them or for the prospective consumers.

Regards,

--

 
My point is that "we" aren't the mass market, and that's what's required to get corporate approval to spend the money to make the cameras that too few will buy. I had my first darkroom when I was 13. I've been through 35mm, 6x7, 4x5, and 5x7, if anyone here wants more resolution and less noise than me he's more than half crazy. But digital is close to saturation in the U.S.. How many more "generations" of cameras are you willing to spring for? In the near term (next 3 years) I've got 1 more in me, and I don't think the DX2 is it. I already own a 14nx (and a D70, D7, and several P&S) and the D2X doesn't bring enough to the table to get me to cough up 5G's. I'm waiting for the next gereration, lower noise FF sensor that can be born from this. If Nikon can change this into a 28MP FF sensor (that will have 1 or more crop factors for using all those DX lenses) in 12-18 months they'll have my money. They're going to do it, so I'm going to wait. But, at that point, with maybe a new 16MP APS and a 28MP FF I think that we're about at the end of the road as far as resolution. The consumers don't need it, and they fund the research. The Foveon technology might finally come into it's own in 3-5 years time, and maybe that'll be the next surge in improvement. BTW any decent lens can resolve more than 125 lp/mm. I tested my 5x7 lenses with aerial projection into a 50x microscope. They all (except for a triplet or two) resolved over 125 lp/mm at f/stops of f/11 or larger. The best was an APO Symmar at > 250 lp/mm @ f/5.6. Leitz claims 400+ lp/mm for their 280 APO. But Joe or Mary down the block, who bought 50 million cameras last year, and do not even own a tripod (and drink too much coffee, and smoke too many cigarettes) would be lucky to see the difference between a Holga and an M6 in their 4x6 prints. I just don't see the economic viability for much more of an improvement in resolution, not at the current costs.

Wayne
to cater to that elitist group?
What makes a person wanting higher resolution elitist?
The same group that USED Ektar25,
Kodachrome25, Agfapan25 and Technical PAN in film cameras. Get my
drift?
Yeah. That was me. I used technical pan and rolled my own
developer. I also shot a lot of Kodachrome. High ISO and large
grain never appealed to me.
APS is close to the end as far as resolution is concerned.
Define close. My take is that we will see APS DSLRs reach around
24Mp. That is still a larger pixel pitch than a CP995 or CP5000.
These cameras may not be the most common and they will probably be
specialty cameras - or perhaps elitist cameras if I take your
apparent point of view.

A great setup would be an X3 type sensor where the camera could
gang pixels in groups of four to halve the resolution for shots
where larger sensor cells and lower resolution would be preferred.
This would actually be a 15Mp sensor count camera but it would have
the resolution of a 25Mp bayer mask camera. In either case, the
lens would have to resolve around 125 lp/mm. I'm not sure how hard
that will be to accomplish.

--
Jay Turberville
http://www.jayandwanda.com
 
it simply isn't needed by anyone that knows what they are doing
(there I said it) or who isn't shooting very very special niche
applications.
I guess I'd say the opposite: Anybody who doesn't want more resolution probably doesn't know what he's doing. (There - I said it.) :-)

Of course, the problem is that more resolution comes at a price in terms of noise, bigger files and camera speed, as well as the gotcha that extra resolution is decreasingly useful because of lens and diffraction limits.

However, if it were technically possible to capture and efficiently manipulate more genuine resolution, then anybody in his right mind would want it. We'd never have to carry big, heavy lenses again. We could put on our favorite wide angle lens, never take it off, and compose in photoshop by cropping our 500MP images on ultrafast computers.

--
Ron Parr
FAQ: http://www.cs.duke.edu/~parr/photography/faq.html
Gallery: http://www.pbase.com/parr/
 
Wayne,

How about 35mm lenses? I thought 60lp/mm and higher is considered a good 35mm lens. Maybe you don't use 50% MTF as the reference?

I am in line with you that 12Mp APS-C and 28Mp FF may be it. Not that resolution won't improve above them, but just that above them one hit the wall of diminishing return.

But, are you willing to spend $5000 on 28Mp FF DSLR? I think this day will come. Maybe not next year, but 3 to 5 years from now. Seeing that it took Canon 2 years to go from 11.1Mp to 16.7Mp for a 50% resolution increase while the price remains the same ($8000). We probably should consider ourselves lucky to see $5000 28Mp FF in 5 years.

For a guy like myself who can't justify spending more than $2000 for a camera, I've given up my hope for a FF DSLR.

Photobug
Wayne
to cater to that elitist group?
What makes a person wanting higher resolution elitist?
The same group that USED Ektar25,
Kodachrome25, Agfapan25 and Technical PAN in film cameras. Get my
drift?
Yeah. That was me. I used technical pan and rolled my own
developer. I also shot a lot of Kodachrome. High ISO and large
grain never appealed to me.
APS is close to the end as far as resolution is concerned.
Define close. My take is that we will see APS DSLRs reach around
24Mp. That is still a larger pixel pitch than a CP995 or CP5000.
These cameras may not be the most common and they will probably be
specialty cameras - or perhaps elitist cameras if I take your
apparent point of view.

A great setup would be an X3 type sensor where the camera could
gang pixels in groups of four to halve the resolution for shots
where larger sensor cells and lower resolution would be preferred.
This would actually be a 15Mp sensor count camera but it would have
the resolution of a 25Mp bayer mask camera. In either case, the
lens would have to resolve around 125 lp/mm. I'm not sure how hard
that will be to accomplish.

--
Jay Turberville
http://www.jayandwanda.com
 
I also wonder if this has anything to do with Canon's decision to
make EF-S lens with shorter back focus distance? Can Nikon do the
same?
This has nothing to do with diffraction.
Hmmm... it does look like 12Mp will be as far as we can go with
APS-C due to diffraction limit. I don't think anyone would like to
shoot with just f/2.8 to f/8, had there been a 20+Mp APS-C, even if
noise maintains low.
Assuming away the other problems with smaller pixels, the only
negative in terms of diffraction is that you don't get the full
benefit of the extra sensor resolution at smaller apertures.

Diffraction never gets worse with smaller pixels. Diffraction just
prevents you from enjoying the full benefits of higher resolution
with small apertures.
The first intelligent thing that I have read in this thread! Up to this point in the discussion everyone acts like a 12mp APS-C at f/11 is worse than a 6mp because of diffraction...er, um, er...come on people! All that this says is that at 12mp and f/11 the LENS is the limfac, while at 6mp and f/11 the sensor is the limfac. Big deal! At the point where any nikkor is limiting the resolution you are still able to produce mammoth prints of extrodinary quality. What more do you want?

Stop over thinking the specs and start over thinking the shooting. ciao!
 
it simply isn't needed by anyone that knows what they are doing
(there I said it) or who isn't shooting very very special niche
applications.
You are simply expressing a personal preference. Why shouldn't we want to record more detail. Why was there a market - and still is - for medium and large format cameras. Just because 35mm film resolution was a practical compromise "yesterday" doesn't mean we necessarily should settle for the same today.

The nice thing about resolution is that having too much generally presents a smaller problem than not having enough.
Nikon needs IMO, to focus on making the same density chip
more sensitive at highier ISO values, shrink the component size per
photosite in the next generation, increase the photoreceptive area,
refine the image processing pipeline, remove the need for noise
reduction so that a standard ISO range of 100 - 1600 is the norm.
Sure. Better high ISO performance would be nice. And for some people, it would be great. But personally, the images that I would shoot at high ISO (indoor sports) are served fine by a 6Mp camera. I have no particular pressing need for higher ISO and higher resolution.

Just like having the choice of film emulsions, we will probably find that we want particular sensors for particular types of shooting. There is no universal "better" approach. There are tradeoffs and different tradeoffs work better in different situations.
The 12mp of the D2x is enough to provide 300dpi prints at 10 x 14,
No, the D2X won't provide 300dpi of detail in a 10x14 print. Just because the sensor has 4228 sensor sites doesn't mean it can record that many "dots". The actual resolution of the typical DSLR sensor is about 80% of what is implied by the sensor site count. So you get about 11.5 inches at 300dpi on the long dimension of a print from a D2x. The Foveon X3 is the only color chip that I know of that will give you a "dot" per sensor site. But then, the 300dpi criteria is overused. Excellent digital prints can be made with much less than 300dpi of actual detail.
more than enough to keep the majority of pro shooters happy (again,
if they know what they are doing)...it's time as consumers that we
demand quality instead of quantity.
I've heard it said that quantity has a quality all its own. I think that applies here.
We already see in the comparisons between the D2x and the Canon
1dsII that the additional 4mp contributes little to extra detail
rendition above the D2x (especially after accounting for
differences in focal length and fov due to the multiplier on the
D2x) or the previous 1Ds.
Precisely. Which is why they should just jump directly to 24mp and be done with it. :)
Here's to a Nikon CMOS gen 2 chip being the same 12mp but with
significantly improved performance at highier ISO values.

Of course I realize this is pretty much a pipe dream, as marketing
will ensure that mp continues to drive development choices but it's
sad that even at the pro level the ignorant quest for more mp
mindless of the drawbacks will lead to eventually to the same slow
drop in quality at highier ISO values over time as occured with
prosumers as they went from 5mp to 8mp.
Its funny that you say this right after pointing out that Nikon has a second generation 12Mp chip that improves high ISO values. High ISO noise is obviously an important issue as well. High resolution and better noise performance are both worth having.

--
Jay Turberville
http://www.jayandwanda.com
 
My point is that "we" aren't the mass market, and that's what's
required to get corporate approval to spend the money to make the
cameras that too few will buy.
Given that the context of the discussion is the Nikon D2x, I really don't see how the mass market enters into the discussion.

But since you brough it up, I agree that Joe sixpack would seldom have a good use for more than 6mp. And even at 6Mp, he is probably "overequipped". But Olympus sells a consumer 8Mp and you can bet everyone else will too. And then it will be 10Mp and so on. If a pro camera has 24Mp, then you can bet that a consumer oriented camera will show up with a similar rating.

The funny thing is that the consumer DSLR is more camera than most of the people who buy one really need. Though there may be one important exception and that is when taking indoor shots of little Jane playing volleyball at the school gym. The DSLRs are great for this. The average person really needs a DX sensor point and shoot similarly sized and setup like the compact 35mm cameras of a few years ago. But they probably wouldn't know to buy it if it was made available cheaply.
I had my first darkroom when I was
13. I've been through 35mm, 6x7, 4x5, and 5x7, if anyone here wants
more resolution and less noise than me he's more than half crazy.
But digital is close to saturation in the U.S.. How many more
"generations" of cameras are you willing to spring for?
I might jump back into SLRs at the 12Mp resolution level. I don't like the bulk of DSLRs nor do I have a pressing need for their better high ISO performance. So I've been sitting it out with my Coolpix 5000 for quite a while. Moving to 6Mp in a DSLR or 8Mp in another digicam seems like a baby step to me. But a move to 12Mp from 5Mp might make sense.

In the meantime, I bought a 4x5 and an Epson 4570 scanner to help me satisfy my high resolution cravings until they make the digital that I want and am willing to pay for. I'm not willing to pay $4-5K either.
BTW any decent lens can resolve more than 125 lp/mm. I
tested my 5x7 lenses with aerial projection into a 50x microscope.
They all (except for a triplet or two) resolved over 125 lp/mm at
f/stops of f/11 or larger. The best was an APO Symmar at > 250 lp/mm
@ f/5.6. Leitz claims 400+ lp/mm for their 280 APO.
The question is whether this aerial resolution will translate into resolution that a sensor can record. Hopefully it will.
But Joe or Mary
down the block, who bought 50 million cameras last year, and do not
even own a tripod (and drink too much coffee, and smoke too many
cigarettes) would be lucky to see the difference between a Holga
and an M6 in their 4x6 prints. I just don't see the economic
viability for much more of an improvement in resolution, not at the
current costs.
Sure. But like I said, this discussion was never about them since they aren't likely customers for the D2x or similar cameras. The higher resolution will be developed and sold to the upper priced markets first and much of it will probably trickle down to Joe and Mary who can brag that their new camera has the same megapixels as the pros. They may not trade in their 6Mp camera for a 25Mp one, but when it breaks, they will probably opt for the higher resolution.

If more is good, then too much should be just right.

--
Jay Turberville
http://www.jayandwanda.com
 
The D2X would be fine for landscape and architectural work, but it
would not be the tool of choice for available light sports
photogtraphy, where the Canon EOS 1D Mark II would be preferable.
Fine, yes. But hardly excellent. At least not as compared to say, 4x5 film.
Ektar 25 was a great film, but you could always drop something
faster into the camera when needed. Most of us can't afford to have
2 or more digital SRLs, so we want a reasonable tradeoff between
resolution and ISO performance.
Are we discussing compromises for the average Joe or the practical technical limits of what could be offered in a DX format sensor? These are two very different discussions. I was discussing the later, not the former.

Most of us can't justify the expense of a 10Mp or above DSLR anyway. So by your reasoning, I could just as easily say that 8Mp is the practical upper limit. 12Mp, after all, just isn't practical for most of us.

My point was that I expect 25Mp or so to be much closer to the limit in resolution for DX sensors. my point wasn't that these higher resolution sensors would mainstream quickly, be cheap and soon be found in the cameras owned by every Joe and Jane. Every Joe and Jane isn't going to buy a D2x either. And neither will most of us enthusiasts. We'll be waiting for the $1200 12Mp "D70 class" camera.

As we type, sub $1000 (and maybe sub $800) bodies are becoming very common. How long before there are some sub-$500 bodies? When this happens, the idea of having two bodies, one for high resolution and the other for low noise at high ISO,will make more sense. The discussion is about the future. Its not about today.

Of course, this is why the notion of an X3 type sensor with gangable photosites is so attractive. If such a sensor could be made, you could have higher resolution or low noise in one camera at the press of a button. You might as well make it "croppable" like the D2x while yer at it.

BTW, its is also worth noting that you reduce noise when you downsize an image. If I resize a high ISO image from my Coolpix 5000 by 1/2, the visible noise drops dramatically as it is averaged out in the resizing process. So it is very reasonable to expect a 20Mp sensor with a sensor pitch the same as my CP5000 to deliver noticably lower noise than the CP5000 if I am simply willing to drop the resolution down to that equal to my CP5000. The real measure of the D2X's or some even higher resolution sensor's noise performance as compared to a 6 or 8Mp DSLR is how the images look when printed the same size. So somewhat poorer noise performance on a per pixel basis isn't such a bad thing when you have more pixels to begin with.
I think one of the things that killed the Kodak full frame digital
was its poor high ISO performance.
Yes, that was probably one of the things (assuming that it really has been "killed"). But the higher resolution is one of the reasons I hear users give for their continued use of these cameras. People aren't exactly giving these cameras away. if I'm wrong about this I will happily make my shipping address available - and I'll spring for the shipping costs. :)

--
Jay Turberville
http://www.jayandwanda.com
 
r
The first intelligent thing that I have read in this thread! Up to
this point in the discussion everyone acts like a 12mp APS-C at
f/11 is worse than a 6mp because of diffraction...er, um, er...come
on people! All that this says is that at 12mp and f/11 the LENS is
the limfac, while at 6mp and f/11 the sensor is the limfac. Big
deal! At the point where any nikkor is limiting the resolution you
are still able to produce mammoth prints of extrodinary quality.
What more do you want?
And the reality is not that at f/11 the resolution is being limited so much as the MTF response with finer detail is being negatively impacted. The D2X's sensor should continue to resolve additional detail all the way to f/22. But at f/22, the MTF response will be very low and hence this detail won't be resolved as "sharply" (it is at the Rayleigh limit here) as it would be at a larger aperture. This is where sharpening can be very useful. So the D2X at f/22 with a very sharp lens should reveal more image detail than a 6Mp sensor of the same size at any aperture. It is only beyond approximately f/22 that basic diffraction physics says you cannot record as much detail as the sensor is capable of.

--
Jay Turberville
http://www.jayandwanda.com
 
I believe Nikon will have a FF iwithin 18 months at $6000. By then the D2x will be ~$4200-$4200 and they may have released a 16MP APS. Given the pixel size in this sensor they could have a 28MP FF - they'll have to. They can't afford not to.

Wayne
How about 35mm lenses? I thought 60lp/mm and higher is considered a
good 35mm lens. Maybe you don't use 50% MTF as the reference?

I am in line with you that 12Mp APS-C and 28Mp FF may be it. Not
that resolution won't improve above them, but just that above them
one hit the wall of diminishing return.

But, are you willing to spend $5000 on 28Mp FF DSLR? I think this
day will come. Maybe not next year, but 3 to 5 years from now.
Seeing that it took Canon 2 years to go from 11.1Mp to 16.7Mp for a
50% resolution increase while the price remains the same ($8000).
We probably should consider ourselves lucky to see $5000 28Mp FF in
5 years.

For a guy like myself who can't justify spending more than $2000
for a camera, I've given up my hope for a FF DSLR.

Photobug
Wayne
to cater to that elitist group?
What makes a person wanting higher resolution elitist?
The same group that USED Ektar25,
Kodachrome25, Agfapan25 and Technical PAN in film cameras. Get my
drift?
Yeah. That was me. I used technical pan and rolled my own
developer. I also shot a lot of Kodachrome. High ISO and large
grain never appealed to me.
APS is close to the end as far as resolution is concerned.
Define close. My take is that we will see APS DSLRs reach around
24Mp. That is still a larger pixel pitch than a CP995 or CP5000.
These cameras may not be the most common and they will probably be
specialty cameras - or perhaps elitist cameras if I take your
apparent point of view.

A great setup would be an X3 type sensor where the camera could
gang pixels in groups of four to halve the resolution for shots
where larger sensor cells and lower resolution would be preferred.
This would actually be a 15Mp sensor count camera but it would have
the resolution of a 25Mp bayer mask camera. In either case, the
lens would have to resolve around 125 lp/mm. I'm not sure how hard
that will be to accomplish.

--
Jay Turberville
http://www.jayandwanda.com
 
No I'm not using MTF, I'm using USAF bar charts (or whatever they are). That's the only reason that there's still room for improvement in digital optics BTW. It seems that although film does O.K. with higher resolution and lower contrast digital sensors really want higher contrast and not so high resolution. That's why zooms look comparatively better on digital than film when compared to primes. The digital sensors aren't using the extra resolution of the primes as well as film can.

Wayne
How about 35mm lenses? I thought 60lp/mm and higher is considered a
good 35mm lens. Maybe you don't use 50% MTF as the reference?

I am in line with you that 12Mp APS-C and 28Mp FF may be it. Not
that resolution won't improve above them, but just that above them
one hit the wall of diminishing return.

But, are you willing to spend $5000 on 28Mp FF DSLR? I think this
day will come. Maybe not next year, but 3 to 5 years from now.
Seeing that it took Canon 2 years to go from 11.1Mp to 16.7Mp for a
50% resolution increase while the price remains the same ($8000).
We probably should consider ourselves lucky to see $5000 28Mp FF in
5 years.

For a guy like myself who can't justify spending more than $2000
for a camera, I've given up my hope for a FF DSLR.

Photobug
Wayne
to cater to that elitist group?
What makes a person wanting higher resolution elitist?
The same group that USED Ektar25,
Kodachrome25, Agfapan25 and Technical PAN in film cameras. Get my
drift?
Yeah. That was me. I used technical pan and rolled my own
developer. I also shot a lot of Kodachrome. High ISO and large
grain never appealed to me.
APS is close to the end as far as resolution is concerned.
Define close. My take is that we will see APS DSLRs reach around
24Mp. That is still a larger pixel pitch than a CP995 or CP5000.
These cameras may not be the most common and they will probably be
specialty cameras - or perhaps elitist cameras if I take your
apparent point of view.

A great setup would be an X3 type sensor where the camera could
gang pixels in groups of four to halve the resolution for shots
where larger sensor cells and lower resolution would be preferred.
This would actually be a 15Mp sensor count camera but it would have
the resolution of a 25Mp bayer mask camera. In either case, the
lens would have to resolve around 125 lp/mm. I'm not sure how hard
that will be to accomplish.

--
Jay Turberville
http://www.jayandwanda.com
 
The D2X would be fine for landscape and architectural work, but it
would not be the tool of choice for available light sports
photogtraphy, where the Canon EOS 1D Mark II would be preferable.
Fine, yes. But hardly excellent. At least not as compared to say,
4x5 film.
But these cameras aren't supposed to replace 4x5's, they're made to replace 35mm cameras. And for the results they deliver to the average Joe they've already done that.
Ektar 25 was a great film, but you could always drop something
faster into the camera when needed. Most of us can't afford to have
2 or more digital SRLs, so we want a reasonable tradeoff between
resolution and ISO performance.
Are we discussing compromises for the average Joe or the practical
technical limits of what could be offered in a DX format sensor?
These are two very different discussions. I was discussing the
later, not the former.
But what's the market? Where's the incentive (read $$$$)?
Most of us can't justify the expense of a 10Mp or above DSLR
anyway. So by your reasoning, I could just as easily say that 8Mp
is the practical upper limit. 12Mp, after all, just isn't
practical for most of us.
At today's prices that is probably true.
My point was that I expect 25Mp or so to be much closer to the
limit in resolution for DX sensors. my point wasn't that these
higher resolution sensors would mainstream quickly, be cheap and
soon be found in the cameras owned by every Joe and Jane. Every
Joe and Jane isn't going to buy a D2x either. And neither will
most of us enthusiasts. We'll be waiting for the $1200 12Mp "D70
class" camera.
I predict that will be a ceiling for awhile - just personal thought.
As we type, sub $1000 (and maybe sub $800) bodies are becoming
very common. How long before there are some sub-$500 bodies? When
this happens, the idea of having two bodies, one for high
resolution and the other for low noise at high ISO,will make more
sense. The discussion is about the future. Its not about today.
But in reality, with good design, you can have both in the same body. The Kodak 14n has 14MP and a reduced 6MP with less noise. With all it's flaws it does show the distinction.
Of course, this is why the notion of an X3 type sensor with
gangable photosites is so attractive. If such a sensor could be
made, you could have higher resolution or low noise in one camera
at the press of a button. You might as well make it "croppable"
like the D2x while yer at it.
I don't understand why this technology isn't progessing more rapidly.
BTW, its is also worth noting that you reduce noise when you
downsize an image. If I resize a high ISO image from my Coolpix
5000 by 1/2, the visible noise drops dramatically as it is averaged
out in the resizing process. So it is very reasonable to expect a
20Mp sensor with a sensor pitch the same as my CP5000 to deliver
noticably lower noise than the CP5000 if I am simply willing to
drop the resolution down to that equal to my CP5000. The real
measure of the D2X's or some even higher resolution sensor's noise
performance as compared to a 6 or 8Mp DSLR is how the images look
when printed the same size. So somewhat poorer noise performance
on a per pixel basis isn't such a bad thing when you have more
pixels to begin with.
Think I mentioned the same.
I think one of the things that killed the Kodak full frame digital
was its poor high ISO performance.
Yes, that was probably one of the things (assuming that it really
has been "killed"). But the higher resolution is one of the
reasons I hear users give for their continued use of these cameras.
People aren't exactly giving these cameras away. if I'm wrong
about this I will happily make my shipping address available - and
I'll spring for the shipping costs. :)
No, I'm going to hang onto mine for a long time to come. With all it's warts it still gives great color, wide dynamic range, FF, and has mirror lock-up (another discussion). It's the only thing preventing me from ordering a D2X right now. As for ISO I don't need higher than 160 for 80% of what I do.

Wayne
 
Fine, yes. But hardly excellent. At least not as compared to say,
4x5 film.
But these cameras aren't supposed to replace 4x5's, they're made to
replace 35mm cameras. And for the results they deliver to the
average Joe they've already done that.
I'm sure that is the way many people approach it, but it is not the only way to look at it. It seems to me that the purpose is not only to replace 35mm film, but to also improve on it. If you can get even better landscapes with the higher resolution sensor, then why not encroach on medium format and possibly even 4x5 film?
Are we discussing compromises for the average Joe or the practical
technical limits of what could be offered in a DX format sensor?
These are two very different discussions. I was discussing the
later, not the former.
But what's the market? Where's the incentive (read $$$$)?
The car makers are selling cars that are far more powerful than anyone "needs" for legal driving. But there is definitely a market. The market is anyone who ever wanted more resolution than 35mm film. Its a small market for sure. And so is the market for the D2x and the other higher resolution DSLRs.
Most of us can't justify the expense of a 10Mp or above DSLR
anyway. So by your reasoning, I could just as easily say that 8Mp
is the practical upper limit. 12Mp, after all, just isn't
practical for most of us.
At today's prices that is probably true.
Right. But the 12Mp and higher cameras are being made anyway.
My point was that I expect 25Mp or so to be much closer to the
limit in resolution for DX sensors. my point wasn't that these
higher resolution sensors would mainstream quickly, be cheap and
soon be found in the cameras owned by every Joe and Jane. Every
Joe and Jane isn't going to buy a D2x either. And neither will
most of us enthusiasts. We'll be waiting for the $1200 12Mp "D70
class" camera.
I predict that will be a ceiling for awhile - just personal thought.
Well for a while for sure. But I don't believe that ceiling will last nor that it is caused by the limits of diffraction. Right now I think it is largely a technology/marketing/price ceiling. Not something dictated fundamentally by diffraction - which was the original question.
The discussion is about the future. Its not about today.

But in reality, with good design, you can have both in the same
body. The Kodak 14n has 14MP and a reduced 6MP with less noise.
With all it's flaws it does show the distinction.
Well yeah. That is the point I make later. Even the poor "per pixel" noise that you might expect from a 25Mp DSLR isn't so poor when you consider it from a per image standpoint. The same think you mention about the 14n would exist for my mythical 25Mp DX sensor as well.
I don't understand why this technology isn't progessing more rapidly.
Join the club. Perhpas part of it is the CMOS design. I understand from other posts that it is difficult to get very small sensor site pitches on CMOS.
No, I'm going to hang onto mine for a long time to come.
Well, if you change your mind ...
As for ISO I don't
need higher than 160 for 80% of what I do.
Right. I suspect most people don't need the low noise, high ISO that DSLRs currently offer. I'm sure its nice to have, but I suspect it isn't a huge benefit to a lot of people. I'd much rather have double the resolution and worse high ISO performance.

--
Jay Turberville
http://www.jayandwanda.com
 
Wayne,

I'm surprised that you are still using the USAF charts. As used with film cameras they measure resolution at about 10% MTF, where the resolution is much higher than the resolution at MTF 50, which correlates better with perceived image sharpness.

As you correctly state, digital sensors can not use resolution at high frequency (the Nyquist limit of the D70 is about 63 lp/mm). Lens resolution above this limit is not useful and would degrade the image via aliasing were the anti-alaising filter not in place. For the D70, it is best to have a lens with high MTF at frequencies below the Nyquist limit as you stated.

Besides, determining resolution from a test chart with high contrast lines with digital imaging is quite difficult and subjective because of alaising, which is not present with film. If you look at Phil's PIMA/ISO 12233 chart image taken by the D70 at 1:1 resolution in Photoshop, you will note that it is very difficult to separate false detail from aliasing from true detail at the higher frequencies.

--
Bill Janes
No I'm not using MTF, I'm using USAF bar charts (or whatever they
are). That's the only reason that there's still room for
improvement in digital optics BTW. It seems that although film does
O.K. with higher resolution and lower contrast digital sensors
really want higher contrast and not so high resolution. That's why
zooms look comparatively better on digital than film when compared
to primes. The digital sensors aren't using the extra resolution of
the primes as well as film can.

Wayne
 
Jay,

Aren't you forgetting that the D2X has an anti-alaising filter that blocks high frequency details above the Nyquist limit of the sensor. Frequencies above the Nyquist limit of the sensor result in aliasing, which degrades the image. That is why the low pass filter is used. For a scientific analysis, refer to this link:

http://www.schneider-kreuznach.com/knowhow/digfoto_e.htm

Low pass filters are not needed with p&s digital cameras, since the lens itself can not resolve above the Nyquist limit of the sensor.

--
Bill Janes
The first intelligent thing that I have read in this thread! Up to
this point in the discussion everyone acts like a 12mp APS-C at
f/11 is worse than a 6mp because of diffraction...er, um, er...come
on people! All that this says is that at 12mp and f/11 the LENS is
the limfac, while at 6mp and f/11 the sensor is the limfac. Big
deal! At the point where any nikkor is limiting the resolution you
are still able to produce mammoth prints of extrodinary quality.
What more do you want?
And the reality is not that at f/11 the resolution is being limited
so much as the MTF response with finer detail is being negatively
impacted. The D2X's sensor should continue to resolve additional
detail all the way to f/22. But at f/22, the MTF response will be
very low and hence this detail won't be resolved as "sharply" (it
is at the Rayleigh limit here) as it would be at a larger aperture.
This is where sharpening can be very useful. So the D2X at f/22
with a very sharp lens should reveal more image detail than a 6Mp
sensor of the same size at any aperture. It is only beyond
approximately f/22 that basic diffraction physics says you cannot
record as much detail as the sensor is capable of.

--
Jay Turberville
http://www.jayandwanda.com
 

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