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Author Topic: Link to Interview with Canon EOS Big Boss  (Read 9389 times)
Er1kksen
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« Reply #20 on: October 04, 2008, 06:32:48 PM »
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Tony, if the large files are the problem for you, why not just use sRAW? You're probably going to get a better file from a 21mp camera downsampling to 10mp than from a camera that shoots 10mp natively due to the benefits of oversampling.

Ray, that's really interesting. The possibility that cameras with higher pixel densities can fish more resolution out of the sensor than a lower-density sensor even when they're both under their diffraction limits is a strong argument for increasing pixel counts as long as noise and DR are not negatively impacted. If we're still using bayer sensors in 10 years, I wouldn't be surprised if our cameras have 40+mp sensors that clearly outresolve our lenses (allowing us to get rid of AA filters and let the lens' sharpness shine through) and most photographers set theirs to downsample to 6-12 mp for most applications. The benefits of oversampling are well worth it if manufacturers can bring down the costs and get DR under control.
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Ray
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« Reply #21 on: October 04, 2008, 07:53:33 PM »
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Quote from: Er1kksen
Ray, that's really interesting. The possibility that cameras with higher pixel densities can fish more resolution out of the sensor than a lower-density sensor even when they're both under their diffraction limits is a strong argument for increasing pixel counts as long as noise and DR are not negatively impacted. If we're still using bayer sensors in 10 years, I wouldn't be surprised if our cameras have 40+mp sensors that clearly outresolve our lenses (allowing us to get rid of AA filters and let the lens' sharpness shine through) and most photographers set theirs to downsample to 6-12 mp for most applications. The benefits of oversampling are well worth it if manufacturers can bring down the costs and get DR under control.

I think it's quite likeley we shall eventually see a 40mp full frame sensor. The cropped formats have always led the way regarding pixel density, and full frame sensors have caught up a few years later. The 5D MkII and 1Ds3 have the pixel density of the 8mp 20D.

DR and noise seems to be largely affected by sensor size. First indications are, the 50D has no 'real' DoF advantage compared with the 5D. In other words, F4, 28mm and ISO 200 with the 50D is no better than F8, 45mm and ISO 800 with the 5D. Both sets of images seem to have about equal resolution and equally low noise.

There might be a slight advantage at very high ISOs, such as the 50D at ISO 3200 compared with the 5D at ISO 1600 underexposed 2, 2 1/2 or 3 stops. The DoF equivalence does not seem to correspond exactly with the 1.6x crop factor. It tends to range between 1 stop and 2 stops' difference depending on distance to subject (and possibly lens design).
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aaykay
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« Reply #22 on: October 04, 2008, 08:47:17 PM »
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Quote from: Christopher
Why ? refining a already designed 21MP sensor is a LOT cheaper than designing a new 16Mp sensor.

I doubt Canon has thrown away the design of the 1DSMKII's 16MP Full-frame sensor, which was cutting edge less than 2 years back.  They just had to  brush it up a bit and with some additional tweaks using the latest technology, it could have done its stuff within the 5DII.  

The advantage would have been that using the same electronics, they could have easily achieved over 5FPS (assuming the shutter is upgraded for 5FPS), since the data coming off the sensor, would have been significantly less, when compared to a 21MP sensor.  

Either way, the deed is done and I doubt Canon would go back to employing a lower pixel density FF sensor in future products.  I personally would have preferred a 14-16MP Full-frame sensor than a 21MP or 25MP Full frame sensor - but that is just me.
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Tony Beach
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« Reply #23 on: October 04, 2008, 11:07:18 PM »
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Quote from: Er1kksen
Tony, if the large files are the problem for you, why not just use sRAW? You're probably going to get a better file from a 21mp camera downsampling to 10mp than from a camera that shoots 10mp natively due to the benefits of oversampling.

It isn't just large files, it's also unnecessary format space.  Often we want to just use the center of the image for telephoto lens shots, and it precisely when doing that sort of shooting that added fps would come in handy.  That's why I prefer Nikon's cropped format approach, which I expect to see in their high MP FX DSLR.

Quote from: Er1kksen
If we're still using bayer sensors in 10 years, I wouldn't be surprised if our cameras have 40+mp sensors that clearly outresolve our lenses (allowing us to get rid of AA filters and let the lens' sharpness shine through) and most photographers set theirs to downsample to 6-12 mp for most applications.

I strongly suspect that many of us won't be using BFA DSLRs in even 5 years:  http://www.imaging-resource.com/NEWS/1186694099.html  Three color photosites are coming, and they will be coming from several directions as I'm sure Canon also has plans to do this.  Imagine 12-16 MP 3 color DSLRs that effectively capture approximately double the resolution of the current BFA DSLRs; the advantages will be higher native ISO, more accurate colors, no more diffraction limitations, smaller files (in a time when computing power will be even greater and storage even cheaper), and the only limitation on fps will be if the AF can keep up (that will also increase as the camera's processing power increases).
« Last Edit: October 04, 2008, 11:07:51 PM by Tony Beach » Logged
dchew
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« Reply #24 on: October 05, 2008, 05:53:40 AM »
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Quote from: Ray
Tony seems to be under the false impression that there's a brick wall regarding diffraction. At one F stop there's a marginal increase in detail, then one stop further down there's zilch. That's not so.

Yes. And this is why these discussions about mp vs. noise vs. image quality always go around in circles.  It's funny to me that when we discuss how to get the highest "technical quality" photographs out of our equipment, we all agree that your entire workflow / technique matters. From accurate focusing, tripods, MLU, correct ISO for the subject, DOF vs. diffraction, camera selection, lens selection, ETTR metering, blah blah.  All these things add up and contribute to an image's technical success.  

Yet when a new camera comes out, we tend to grab on to some specific feature/improvement and evaluate it to death, treating it as if every other input to the IQ process is either static or zero (ex: Nikon's high ISO marketing, Canon's high MP marketing).  Often before there's any way to confirm, evaluate or prioritize the improvement.

Not only that, but the priority of these inputs is subject-dependent, as Michael pointed out in his equipment selection for Botswana.  So people value different features/improvements that affect IQ differently.  From polling thousands of posts, I have confirmed that Canon shooters always print > 40"x60", and Nikon shooters always use ISO > 3200.  :~) [if I may borrow Schewe's logo just once]

Would the 5D be "better" with 16mp instead of 21?  We'll never know because they didn't make one.  My guess is in most cases it would be awfully difficult to tell anyway.  But I'm sure someone will devise a test that proves yes.  And no.

Dave Chew
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Graeme Nattress
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« Reply #25 on: October 05, 2008, 08:01:56 AM »
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Quote from: Tony Beach
It isn't just large files, it's also unnecessary format space.  Often we want to just use the center of the image for telephoto lens shots, and it precisely when doing that sort of shooting that added fps would come in handy.  That's why I prefer Nikon's cropped format approach, which I expect to see in their high MP FX DSLR.



I strongly suspect that many of us won't be using BFA DSLRs in even 5 years:  http://www.imaging-resource.com/NEWS/1186694099.html  Three color photosites are coming, and they will be coming from several directions as I'm sure Canon also has plans to do this.  Imagine 12-16 MP 3 color DSLRs that effectively capture approximately double the resolution of the current BFA DSLRs; the advantages will be higher native ISO, more accurate colors, no more diffraction limitations, smaller files (in a time when computing power will be even greater and storage even cheaper), and the only limitation on fps will be if the AF can keep up (that will also increase as the camera's processing power increases).

Move to an approach like  you post to won't help matters significantly. The primary reason a Sigma with it's foveon has a higher measured resolution is that it omits an optical low pass filter from it's design, and hence allows through all manner of nasty moire and aliasing artifacts. Hence a lot of it's resolution is fake, and a lot of it corrupts real lower frequency data. As pointed out above Canon fully understand the necessity for correct optical low pass filtering and will not make a camera that aliases nastily. Also, such a method is still  using the same silicon area for the three receptors as you'd use in a CFA design - it's essentially an RGB stripe pattern CFA with a complex lens structure on top of it, so to get higher resolution, you'll  have to move to smaller photosites and higher noise. Assuming you have the technology to make those smaller photosites less noisy - at that point, placing them in a Bayer CFA will give you more perceptually relevant resolution than the stripe+dichroic mirror approach. Indeed, unless you really like the way a dichroic mirror splits up the colour spectrum, you may as well just go with a plain RGB stripe CFA and let the optical low pass filter ensure that each triplet gets pretty much the same light  hitting it.... And have a lot cheaper sensor with similar noise and resolution characteristics.
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Slough
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« Reply #26 on: October 05, 2008, 08:27:44 AM »
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I take Canon interviews with a piece of salt as past performance has shown them to be more of a marketing exercise than anything else.

As for high MP, it is also more of a marketing wheeze than anything else. They know that consumers compare specs, and the most obvious one is the MP count. That is why Point and Shoot cameras now have absurd pixel counts. In practice a user will not be able to realise the MP count of the 50D unless using a small number of high performance lenses. Others will have so much CA and softness in the corners as to make the exercise pointless. Most example pictures on sites such as DPREVIEW are awful. Even with the best lenses, you will only be able to use certain apertures. Stop down to F11 for DOF, and the chances are the limitation will be the lens, not the sensor. For macro work you generally need to stop down to F11 at least, in which case there is not much point going beyond 12MP. Oh, and to realise the resolution you will need to use a tripod of course, or high shutter speeds.  

Canon should IMO have stuck with 12 MP, or even 10MP, and concentrated on improved noise and DR. They would then have had a class leading camera with real advantages. As it is, they simply have more MP which most of the time is of no use, and yet file sizes are bigger. Oh, and the need to shunt more data through the circuitry means you need more complex electronics, hence putting up the price. Smaller file sizes might have allowed faster frame rates too.

Not so long ago people were responding to the Nikon D200 by saying that the 8MP of the Canon 30D was more than enough, and 10MP was too much. Hi ho.
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Ray
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« Reply #27 on: October 05, 2008, 08:35:04 AM »
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Quote from: dchew
Would the 5D be "better" with 16mp instead of 21?  We'll never know because they didn't make one.  My guess is in most cases it would be awfully difficult to tell anyway.  But I'm sure someone will devise a test that proves yes.  And no.

Dave Chew

Dave,
The 50D can be considered as a crop of a 40mp full frame 35mm DSLR. Even with a medium quality zoom like the Canon 100-400 IS, 40mp is more detailed than the 12.7mp of the 5D, not only at F8 and F11 (the apertures at which this lens is sharpest) but even at F22, although the improved detail at F22 is very slight.

Below is the full scene followed by 200% crops at the plane of focus, at F22 and F11. At F11, the 5D is not even capable of showing the corrugations of the roof.

These image have had only default conversion in ACR plus a slight adjustment of brightness to equalize the appearance. ISO was 400 for both cameras.


[attachment=8710:The_scene.jpg]  [attachment=8711:F22_Vert...es_200__.jpg]  [attachment=8712:F11_Vert...es_200__.jpg]

[attachment=8713:F11_roof.jpg]
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Slough
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« Reply #28 on: October 05, 2008, 10:18:03 AM »
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Quote from: Ray
Dave,
The 50D can be considered as a crop of a 40mp full frame 35mm DSLR. Even with a medium quality zoom like the Canon 100-400 IS, 40mp is more detailed than the 12.7mp of the 5D, not only at F8 and F11 (the apertures at which this lens is sharpest) but even at F22, although the improved detail at F22 is very slight.

Below is the full scene followed by 200% crops at the plane of focus, at F22 and F11. At F11, the 5D is not even capable of showing the corrugations of the roof.

These image have had only default conversion in ACR plus a slight adjustment of brightness to equalize the appearance. ISO was 400 for both cameras.


[attachment=8710:The_scene.jpg]  [attachment=8711:F22_Vert...es_200__.jpg]  [attachment=8712:F11_Vert...es_200__.jpg]

[attachment=8713:F11_roof.jpg]

What you show is hardly surprising since the 5D corresponds to ~5MP when cropped, though the difference between the images with the lens at F22 is as good as nothing IMO. I thought the issue in this thread was whether or not 15 MP was an advantage compared to ~12MP.
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Tony Beach
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« Reply #29 on: October 05, 2008, 11:15:51 AM »
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Quote from: Graeme Nattress
Move to an approach like  you post to won't help matters significantly.

I can think of two things that are significantly improved.

First is file sizes will be smaller; you can uprezz in software and use that function to eliminate aliasing.

Second is diffraction limitations can be moved a stop or more higher, which delivers more practical resolution at higher f/stops.
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Graeme Nattress
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« Reply #30 on: October 05, 2008, 04:13:17 PM »
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Uprezzing in software doesn't eliminate aliasing.

Diffraction limiting is down to the size of the pixel. If the pixel gets smaller, you've just traded resolution for noise.

If you have the same number of photosites in a different arrangement, then you get the same file size (assuming no compression).

Graeme

Quote from: Tony Beach
I can think of two things that are significantly improved.

First is file sizes will be smaller; you can uprezz in software and use that function to eliminate aliasing.

Second is diffraction limitations can be moved a stop or more higher, which delivers more practical resolution at higher f/stops.
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Ray
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« Reply #31 on: October 05, 2008, 06:59:00 PM »
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Quote from: Slough
What you show is hardly surprising since the 5D corresponds to ~5MP when cropped, though the difference between the images with the lens at F22 is as good as nothing IMO. I thought the issue in this thread was whether or not 15 MP was an advantage compared to ~12MP.

Whether one is comparing 15mp with 5mp at a cropped-format size, or 39mp with 12.7mp at a full frame size, the differences are the same because the pixel densitiies are the same.

Whether or not you think the extra detail at F22 is worth anything, is a matter of opinion and will depend on your purposes. I'm merely presenting the facts and demonstrating that there is no brick wall effect within the aperture range that most 35mm lenses have, as one stops down, even with a 15mp cropped format sensor, and by extrapolation, a 39mp full frame sensor.

As a matter of fact, I can think of circumstances where that extra detail at F22, most apparent in the vertical stripes of the curtains and the brickwork of the window sill, could make the difference of being able to identify a face, the make of vehicle or any object in the scene for espionage purposes or even general historical purposes, if that were the only shot available.

Edit: The other issue I haven't addressed is the additional detail at F22 which should be apparent at a sufficient distance away from the plane of focus. The purpose of stopping down is usually to gain a greater DoF, albeit sometimes at the expense of some loss of detail at the plane of focus. The scene I shot for this comparison was focussed at or very close to infinity. There's nothing in the scene which is outside of the hyperfocal distance range, with either camera.
« Last Edit: October 05, 2008, 07:15:39 PM by Ray » Logged
Ray
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« Reply #32 on: October 06, 2008, 07:11:12 PM »
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Quote from: Ray
Edit: The other issue I haven't addressed is the additional detail at F22 which should be apparent at a sufficient distance away from the plane of focus. The purpose of stopping down is usually to gain a greater DoF, albeit sometimes at the expense of some loss of detail at the plane of focus. The scene I shot for this comparison was focussed at or very close to infinity. There's nothing in the scene which is outside of the hyperfocal distance range, with either camera.

I was a bit too quick with that comment. Only from F16 to F32 are the 50D images within the hyperfocal range at all points. From F5.6 to F16 there's a very noticeable progression of increased clarity in the parts of the image closest to the camera. This increase in detail even at F22 (compared with F8), at the closest point to the camera, is significantly greater than the increase in detail at the plane of focus in the F8 shot, compared with the F22 shot, at the plane of focus.

In other words, even with a 39mp full frame DSLR, there could still be a good reason for using F16 and even F22 when extensive DoF is a priority. The loss of resolution at the plane of focus, due to the effects of diffraction, appears to be less than the increase in resolution away from the plane of focus.

The first set of crops below shows the progressive loss of resolution at the plane of focus, moving from F8 to F32. The second set of crops shows the progressive increase in resolution at the closest point to the camera.

[attachment=8737:F5_6_to_...0__crops.jpg]  [attachment=8738:F5_6_to_...reground.jpg]

Of course, it hardly needs mentioning, if the 400mm lens had been a high quality prime instead of a medium quality zoom, the crop at F8 (at the plane of focus) would have been noticeably sharper than the crop at F11, instead of being roughly equally sharp. And the crop at F5.6 would have been clearly the sharpest, instead of being marginally less sharp than the F8 crop.

The Canon 100-400 IS is a lens that definitely needs upgrading. For all I know, perhaps recent copies of this lens actually have been improved. There's no reason why Canon should announce each marginal improvement in their production processes and quality control. This design has been around for a long time.
« Last Edit: October 06, 2008, 07:54:58 PM by Ray » Logged
Slough
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« Reply #33 on: October 20, 2008, 04:49:48 AM »
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Quote from: Ray
Whether one is comparing 15mp with 5mp at a cropped-format size, or 39mp with 12.7mp at a full frame size, the differences are the same because the pixel densitiies are the same.

Whether or not you think the extra detail at F22 is worth anything, is a matter of opinion and will depend on your purposes. I'm merely presenting the facts and demonstrating that there is no brick wall effect within the aperture range that most 35mm lenses have, as one stops down, even with a 15mp cropped format sensor, and by extrapolation, a 39mp full frame sensor.

As a matter of fact, I can think of circumstances where that extra detail at F22, most apparent in the vertical stripes of the curtains and the brickwork of the window sill, could make the difference of being able to identify a face, the make of vehicle or any object in the scene for espionage purposes or even general historical purposes, if that were the only shot available.

Edit: The other issue I haven't addressed is the additional detail at F22 which should be apparent at a sufficient distance away from the plane of focus. The purpose of stopping down is usually to gain a greater DoF, albeit sometimes at the expense of some loss of detail at the plane of focus. The scene I shot for this comparison was focussed at or very close to infinity. There's nothing in the scene which is outside of the hyperfocal distance range, with either camera.

Unfortunately you did not clearly label your images so we do not know what you are comparing. Could you explain what each photo was taken with? That would avoid confusion. Then I can comment.
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Ray
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« Reply #34 on: October 20, 2008, 09:38:09 AM »
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Quote from: Slough
Unfortunately you did not clearly label your images so we do not know what you are comparing. Could you explain what each photo was taken with? That would avoid confusion. Then I can comment.

I'm comparing resolution at various F stops with the 5D and 50D. The name of the camera, the f stop and the focal length appear at the top of each photo, except for the two groups of 6 images in my previous post which were all taken with the 50D to demonstrate DoF issues, that resolution even at F16 can be higher than at F8, at least somewhere in the scene.

There seems to be some fallacy that there is no point in using a 15mp cropped format sensor stopped down below F8 because there is no resolution advantage with current lenses. My tests indicate this is just not true. Other tests I've done recently, comparing the 40D with the 50D, indicate that a 50D at F13 can provide the same detail as a 40D at F8 at the plane of focus, with same lens, but significantly more detail away from the plane of focus, as a result of the greater DoF that F13 affords.
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