5D Mark III/X Information [CR1]

[NotABunny]

The idea that "pixel (= singular) equates image (all pixels)" is wrong. Having smaller pixels reduces the amount of light gathered by individual pixels, not by the ENTIRE sensor.

Besides this, noiser images isn't even equivalent to worse looking images for a human. http://www.cambridgeincolour.com/tutorials/image-noise-2.htm shows that a higher resolution (= smaller pixels) is perceived as "less noisy".

The explanation is: "If the two patches above were compared based solely on the magnitude of their fluctuations (as is done in most camera reviews), then the patch on the right would seem to have higher noise. Upon visual inspection, the patch on the right actually appears to be much less noisy than the patch on the left. This is due entirely to the spatial frequency of noise in each patch."

(Search for this explanation and look at the images above it.)

sublime LightWorks, you have claimed to have images that prove otherwise. Please show them. Please show images taken in identical conditions: amount of light, shutter speed and aperture. Also use cameras with similar technology, don't compare techonology separated by years of development.

That test is extremely poorly done.

The reality of the situation is that generally the more pixels you have, the more noise a camera will have. Not because the pixels somehow cause the noise, but because it reduces the light gathering ability of the camera's sensor.

Anyways I encourage people to read about the quantum efficiency of a sensor:

http://www.sensorgen.info/

I'll take physical evidence instead. If you have any that supports what you're saying, please show that. Please show images taken in identical conditions: amount of light, shutter speed and aperture. Also use cameras with similar technology, don't compare technology separated by years of development.



Here is my previous post on this endless battle about comparing IMAGES with IMAGES: http://www.canonrumors.com/forum/index.php/topic,3143.msg66274.html#msg66274

You can read a detailed explanation about how to compare IMAGES (not pixels) (with a link to samples from 1D4 and D3s) here: http://www.canonrumors.com/forum/index.php/topic,255.msg3911.html#msg3911


And by the way, Radiating, the normalized images appear to have a simlar noise despite your claim that QE has a visible effect. D3s has 57%, 1D4 has 44%.

[Ivar]

Smaller pixels perform better at high-ISO all the way until read noise starts to dominate

I'm in no way scientist but looking at the D800 examples and per area comparison of phone cameras there must be some truth in it.

[sublime LightWorks]

Ok, let's say this is correct (I'm not buying this as I can point to 1000 other examples of images taken where this is not the result).  Can you explain why comparisons of exactly the same RAW images taken with a 5Dmk2 at ISO 3200 are so much cleaner than the 7D?  The 7D has a far smaller pixel, but tests done on many sites comparing it to the 5Dmk2 clearly show the degraded IQ on the 7D at the same high ISO levels.  And the 3Mpix difference between the 5Dmk2 and the 7D is not enough to account for that.

Because he was talking about a normalized comparison and you were talking about a 100% view comparison.
Per area of sensor the 7D actually seems to have a tiny bit LESS noise than the 5D2, however, the 5D2 has a LOT more area. So long as you are willing to shoot wide open and this with the same ISO, aperture and shutter speed and can frame the shoot as you desire with the lens you have and don't need to crop way in onto a distant bird or something, the 5D2 result is better. But if you are distance limited then you end up comparing based on how well they do per area of sensor if you want to compare them fairly or by 100% view if you want to compare detail and in either case the 7D actually beats the 5D2 (although it's not by any amount to really care about when it comes to the noise).

DPReview has examples of this in their 7D review and analysis.  And since I own both the 5Dmk2 and the 7D, I can tell you in the real world, the 7D cannot hold a candle to the 5Dmk2 at ISO 1600 or above.

It can if you are distance limited. And the fair comparison here, in the general sense, would be to imagine the 7D sensor not being clipped off at APS-C size but extended to FF size, then with it's slightly better performance per area and equal area you'd see that it's actually doing a trace better despite having much, much smaller photosites. It does have newer technology, but even if it did not it probably would not end up looking more than maybe 1/2 stop worse at worst.

In rare cases it can even look better at ISO3200 even in a non-distance limited case if the scene consists mostly of deep shadows since it has less banding there. But usually, when you can frame as you desire and if oyu use the same exposure, yeah the 5D2 will look better than the 7D, but it's really because the 5D2 has an amazing 2.56x the surface area to collect light over due to the much larger sensor.

Ah.....ok, I see where you're going.  Have to chew on that a bit.

Office schedule today is ugly, so I may not be back until Friday with a followup, but thx for that slice of info.  It helps.

-B

[sublime LightWorks]

In the past I believe the AF was either controlled by the main CPU (which generally hadn't been the digics, but an additional chip AFAIK) or an additional AF only CPU.

On the 1DX they will use a Digic iv as the AF chip.

Most of the rumors have mentioned single digic V for image throughput and some have also mentioned digic iv for AF. Who knows if any of this stuff is for real, the 22MP or 7fps either.

Anyway I don't think 3 digics, if it came to that, shoud be a shock in the general sense (coming from Canon, yes, perhaps). How much do you think a digic iv costs? they use them in the lowest of lowest priced Canon P&S cameras. And, I forget, but I thought they added a separate CPU for AF even in the 7D, although not a digic chip.

Why is it so insane to think (other than because of the sort of company Canon has become)? Other companies do it. If you think it is all insane, in principle (in reality, perhaps you are correct), you've had too much of the Canon kool-aid.

Definitely not drinking the Canon kool-aid, far from it. 

Let's drive on that idea of 3 processors.  Could all that fit in a 5D body?  I'm thinking no, but.....it's possible.  Looking at the circuit board images of the 1Dx, I have a hard time thinking that hardware is going to fit in a 5D body.  Gotta remember, that 1Dx has the advantage of the room offered by the built-in grip.

In the 7D it uses the dual Digic's for the AF as well....check the specs and the circuit board layout...nothing indicates another AF processor in addition to the Digics.

I'll have to check but I could swear they said they added a little chip for 7D AF.

Well the 7D proves they can fit two digics and an additional master cpu and maybe a small additional AF CPU.

However, the digic chips do seem to take up more surface area than any of the other chips. Is there room to fit in three digic chips? Not sure. I'd have to look at the boards and think. It's possible you could have a point there if there is nothing else they can shrink or move around.

OK, let me see, well a quick bit of google quickly turns up lots of references to a dedicated AF chip being used in the 7D. So I think it has, but I think this chip must be noticeably smaller than a digic sin emy vague recollection was a circuit board with two big digics and then a bunch of much small chips, if I recall correctly (and I might not be).

I managed to find a very, very tiny pic of the 7D mainboard, it's so small that it is hard to say, it looks like they might just be able to cram in another digic, but it depends. Image it too small to really tell and perhaps the Digic 5 is much larger, etc.

There's a big blowup of the 7D circuit board on the DPReview of it.  The only two chips marked are the Digic's, none of the others have any markings, but there are a couple small chips on the board.  Compare that to the 1Dx and that's a pretty big up in real estate circuit board.

A fast scan of the online info at Canon's site did not reveal any mention of an additional chip, nor did the DPReview article, but I know I have a white paper from Canon on the 7D AF I downloaded when I was tearing into how to properly use the AF system (coming from the 40D, 50D, and 5Dmk2 experience).  I see the AF chip mentioned in some google articles as you noted, and will look into those as well. 

If the 5Dx does turn out to have the full 1Dx AF and metering, I have to venture a guess that one Digic-5 can handle the pixel load at 7fps, along with the remaining camera functions, with the Digic-4 doing the AF per the 1Dx system.

And I hear you on the scaling not necessarily being a 2x in performance with two processors, we can witness that in multi-core processors not scaling by 100% per core.  I'm typing this on a 6-core AMD box I built and frankly, unless it's running well-threaded code or several apps at once, it's not that much faster than the 4-core CPU it replaced.  Since we don't know how well threaded Canon's software is, we really can't determine the final scaling factor.

Which brings up another interesting point.....if they can put dual and quad core processors in a cell phone, why hasn't Digic gone to dual or quad core?  Maybe that's the next rev.....could you imagine the ability of a couple of dual core Digic-5's, or mounting a quad core single Digic in a 7Dmk2?

-B

[sublime LightWorks]

sublime LightWorks, you have claimed to have images that prove otherwise. Please show them. Please show images taken in identical conditions: amount of light, shutter speed and aperture. Also use cameras with similar technology, don't compare technology separated by years of development.

NotABunny, please re-read and take a few mins to comprehend what I posted:

DPReview has examples of this in their 7D review and analysis.  And since I own both the 5Dmk2 and the 7D, I can tell you in the real world, the 7D cannot hold a candle to the 5Dmk2 at ISO 1600 or above.

As I stated, comparing real world images, in similar circumstances (shot same day, same conditions, same ISO), you can clearly identify the 5Dmk2 image when placed next to the 7D image. This is not just me, its observed by several who looked at the shots taken, including clients and other photographers.

This was not some test, not some scientific analysis, not Consumer Reports labs.   There was no claim to have images that "prove" anything other than that simple observable fact...equivalent images from both cameras show the 5Dmk2 looks superior to the 7D.  If that result is more from the 5Dmk2 sensor size than the pixel size, as several have indicated in replies, then that is helping me to understand the specifics of the physics and optics involved in the image produced by the camera.

Just as others here have observed that, to them, the D800 images look as good or better than the 5Dmk2, it's currently by observation of that effect.  There has been no RAW comparison to date to prove this.  Your demand that I produce such images that "prove" fails to understand my statement:  when shown side by side, the 7D images appear "grainier" and "noisier" at ISO's 1600 and 3200 than a similar photo taken by the 5Dmk2.  The IQ in the 5Dmk2 simply looks superior to a given equivalent shot on from a 7D.  If the reasons for this apparent image superiority are not due to pixel size/pixel noise and that pixel size has little to contribute the actual noise levels witnessed, then that knowledge is educating me and is most welcome.

Further, your request to "Please show images taken in identical conditions: amount of light, shutter speed and aperture. Also use cameras with similar technology, don't compare technology separated by years of development" seems to indicate there is something to prove here and you're out to "win" this discussion.  Wrong my friend, for one I don't have a plethora of equipment available to me to satisfy your adhoc conditions and I seriously doubt you could do the same.  Second, I could care less about "proof" when all the proof I personally require is what my client sees when comparing a couple of images.  It's their cash, satisfaction, and job referrals that is the proof enough for me.

I don't view this as some contest to see who is right and who is wrong.  It's an attempt to foster a discussion and in the process, understand the underlying technology, how it's applied, and how to make better purchasing decisions when considering the various options in the marketplace.  If you're looking for a forum discussion trophy by "winning" something, you're engaging the wrong person and I suggest you go elsewhere to find a deer to mount on your wall.  Homie don't play dat.

**** To all the others who have replied on this topic, I greatly appreciate your time, efforts, and willingness in describing the physical principles and technologies involved.  While I have a BSEE (1984), I don't get to use the damn thing these days, my BSCS and MBA play a much bigger role in my IT director position.  But I still fully understand the technical details of the discussed (and much more).

[NotABunny]

As I stated, comparing real world images, in similar circumstances (shot same day, same conditions, same ISO), you can clearly identify the 5Dmk2 image when placed next to the 7D image.

when shown side by side, the 7D images appear "grainier" and "noisier" at ISO's 1600 and 3200 than a similar photo taken by the 5Dmk2.  The IQ in the 5Dmk2 simply looks superior to a given equivalent shot on from a 7D.  If the reasons for this apparent image superiority are not due to pixel size/pixel noise and that pixel size has little to contribute the actual noise levels witnessed, then that knowledge is educating me and is most welcome.

The reason why the entire image from 5D2 looks cleaner is because it has a sensor that is 1.6 * 1.6 (= the crop factor) times larger than that of 7D. This is 2.56 times, meaning that it's log2( 2.56 ) = 1.35 stops cleaner. This is the expected difference.

This happens because images have a physical size, and this size is the size of the sensor. The larger sensor captures more light for the same photo. This can't be seen practically because the images are always scaled to display / paper size (= the same physical size), but with different scales. The images made by a sensor as large as a display don't need to be scaled at all (compared to a small FF sensor) and would therefore show stupefyingly low noise levels (for the entire photo). Unfortunately, the lens needs to be proportional in diameter.

[simonxu11]

All the sample pics I've just posted can be downloaded from here
https://rapidshare.com/files/498221805/D800_sample_by_Arnaud.rar

Thx for that link, very much appreciated....downloading now.......thank god I have UVerse.

Geez, all the pics were shot by 5d mark ii! It has been confirmed!
A Canon fanboy did this and posted them to a Nikon forum, then he hided in shadow while hearing all the compliments about how good the D800 is from all Nikon users!

[libertyranger]

All the sample pics I've just posted can be downloaded from here
https://rapidshare.com/files/498221805/D800_sample_by_Arnaud.rar

Thx for that link, very much appreciated....downloading now.......thank god I have UVerse.

Geez, all the pics were shot by 5d mark ii! It has been confirmed!
A Canon fanboy did this and posted them to a Nikon forum, then he hided in shadow while hearing all the compliments about how good the D800 is from all Nikon users!

That is awesome!! What forum?

[sublime LightWorks]

All the sample pics I've just posted can be downloaded from here
https://rapidshare.com/files/498221805/D800_sample_by_Arnaud.rar

Thx for that link, very much appreciated....downloading now.......thank god I have UVerse.

Geez, all the pics were shot by 5d mark ii! It has been confirmed!
A Canon fanboy did this and posted them to a Nikon forum, then he hided in shadow while hearing all the compliments about how good the D800 is from all Nikon users!

Are you freaking kidding me???  LOL....that is hilarious.....

I'd love a link to that discussion.

[sublime LightWorks]

As I stated, comparing real world images, in similar circumstances (shot same day, same conditions, same ISO), you can clearly identify the 5Dmk2 image when placed next to the 7D image.

when shown side by side, the 7D images appear "grainier" and "noisier" at ISO's 1600 and 3200 than a similar photo taken by the 5Dmk2.  The IQ in the 5Dmk2 simply looks superior to a given equivalent shot on from a 7D.  If the reasons for this apparent image superiority are not due to pixel size/pixel noise and that pixel size has little to contribute the actual noise levels witnessed, then that knowledge is educating me and is most welcome.

The reason why the entire image from 5D2 looks cleaner is because it has a sensor that is 1.6 * 1.6 (= the crop factor) times larger than that of 7D. This is 2.56 times, meaning that it's log2( 2.56 ) = 1.35 stops cleaner. This is the expected difference.

This happens because images have a physical size, and this size is the size of the sensor. The larger sensor captures more light for the same photo. This can't be seen practically because the images are always scaled to display / paper size (= the same physical size), but with different scales. The images made by a sensor as large as a display don't need to be scaled at all (compared to a small FF sensor) and would therefore show stupefyingly low noise levels (for the entire photo). Unfortunately, the lens needs to be proportional in diameter.

I'm hearing you....and thank you for the well written reply.

When you say "This is 2.56 times, meaning that it's log2( 2.56 ) = 1.35 stops cleaner. This is the expected difference.", I'm assuming you also meant to add "Given the same technology generation."  Otherwise, without it, that would question why a sensor of the same size in another camera shows a different level of noise.

That said, if I understand what you are saying......

"Generally, given a sensor of the same size and technology level/generation, and operated at the same sensitivity level (ISO), the one that has more pixels (smaller pixel size) will demonstrate a visibly lower level of noise in comparison to its larger (fewer) pixel sibling.  The pixel size is not a factor in the noise generated, but the greater number of pixels in the same sensor area has the effect of reducing the overall level of noise in the captured image."

That about right?

[LetTheRightLensIn]

D800 ISO test from ISO50-ISO25600
http://info.xitek.com/pzreview/hwtest/201202/14-75122.html

I cannnot find an English version although the website above claims it is from facebook

First pic is ISO3200, second is ISO6400

@6400 is very useable to my eyes

How can you tell when they are downsized to 2MP?

[LetTheRightLensIn]

All the sample pics I've just posted can be downloaded from here
https://rapidshare.com/files/498221805/D800_sample_by_Arnaud.rar

Thx for that link, very much appreciated....downloading now.......thank god I have UVerse.

Geez, all the pics were shot by 5d mark ii! It has been confirmed!
A Canon fanboy did this and posted them to a Nikon forum, then he hided in shadow while hearing all the compliments about how good the D800 is from all Nikon users!

Haha, well my point about them having been too downsized to be able to tell anything is now entirely moot.
Even if they had been it still would be hard to tell, even if they were full 36MP and from the D800, who knows about lighting, exposure, processing, etc. But any it's all moot haha.

[simonxu11]

All the sample pics I've just posted can be downloaded from here
https://rapidshare.com/files/498221805/D800_sample_by_Arnaud.rar

Thx for that link, very much appreciated....downloading now.......thank god I have UVerse.

Geez, all the pics were shot by 5d mark ii! It has been confirmed!
A Canon fanboy did this and posted them to a Nikon forum, then he hided in shadow while hearing all the compliments about how good the D800 is from all Nikon users!

Are you freaking kidding me???  LOL....that is hilarious.....

I'd love a link to that discussion.

If you guys can read Chinese 

[DBCdp]

Wow! The arguments that go on and on comparing the 7D to the 5D MkII. I owned the 5D, 7D, and 5D MkII at the same time. Used all 3 in weddings. The 5D Classic had cleaner images than the 7D right up to 1600 ISO. The 7D simply does not compare in image quality to the 5's, either of them. Which is why I will be passing my 7D on and getting either another 5D MkII or the new 5D? in the next week, announced or not.

I just looked at hundreds of pictures today, thinking new glass might be my best bet, and the final result of that is that the 7 just simply doesn't take the clarity of pictures I've come to expect from the full frame cameras. Period. And of course, that's my opinion based on the camera bodies I had in my hands, so anyone else's experience may differ from mine. But even at sporting events in broad daylight, the images from the 7 just didn't have that crystal clear you-were-there look to them that has become my standard.

[EchoLocation]

All the sample pics I've just posted can be downloaded from here
https://rapidshare.com/files/498221805/D800_sample_by_Arnaud.rar

Thx for that link, very much appreciated....downloading now.......thank god I have UVerse.

Geez, all the pics were shot by 5d mark ii! It has been confirmed!
A Canon fanboy did this and posted them to a Nikon forum, then he hided in shadow while hearing all the compliments about how good the D800 is from all Nikon users!

Are you freaking kidding me???  LOL....that is hilarious.....

I'd love a link to that discussion.

If you guys can read Chinese 

My Fiance is Chinese. I need to see this if you have a link. I can get some good translations in later if you have  a link.
Sounds epic.