Canon will release four new full-frame cameras in 2020 [CR2]

SteveC

M6 mk II
Sep 3, 2019
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A cropped sensor will always perform worse than a larger one. You can't cheat physics.
Why would pixels perform worse just because other pixels have been cropped out by a cropped mode?

Or perhaps that's not what you're saying. But jedy was talking about a ff sensor in a crop mode, not about a physicially smaller sensor versus a larger one. When you operate a FF sensor in a cropped mode, the ONLY penalty in performance should be that large parts of the image go away. The pixels that remain shouldn't be any noisier than they were before.

I'd certainly expect an APS-C sensor of (say) 32MP to do worse than a full size sensor of 32MP (all else being the same), but that's not what he was talking about; the appropriate comparison for what jedy was talking about would be an FF 83 MP running in some sort of crop mode and giving 32MP images, versus an APS-C 32MP sensor. Those two should have identical performance, provided the same tech was used to create both sensors.
 
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jedy

EOS 80D
Feb 14, 2014
117
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The R and RP do that now. attach an EF-S lens, and it auto-crops.
Yes but I am predicting a crop mode will eventually replace high end crop cameras like the 7D line. Not just auto cropping for EF-S lenses but letting the user have both selectable options for all lenses (do the R & RP allow this? I don’t know). We’re seeing this already in mirrorless cameras. Also with it being a crop of a FF sensor, maybe future technology can improve the crop performance over what crop sensors currently achieve?
 

AlanF

Canon 5DSR II
Aug 16, 2012
6,248
4,146
Yes but I am predicting a crop mode will eventually replace high end crop cameras like the 7D line. Not just auto cropping for EF-S lenses but letting the user have both selectable options for all lenses (do the R & RP allow this? I don’t know). We’re seeing this already in mirrorless cameras. Also with it being a crop of a FF sensor, maybe future technology can improve the crop performance over what crop sensors currently achieve?
If you are using the full area of FF and APS-C crop and viewing the output of both at the same size, the FF at higher isos will always beat out a crop. And current sensors are so good that their efficiencies can't be improved enough for a future APS-C to have lower noise than a current FF. Which is not to say that current APS-Cs are not good, they are darned good and more than capable for most situations.
 
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Michael Clark

Now we see through a glass, darkly...
Apr 5, 2016
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It all depends on how you look at it.
Essentialy, the quantum efficiency of all the latest cameras is the same within a few percent. The days of big differences between models and manufacturers is over. Everyone is within a half stop.

With the same amount of photons hitting the sensor, pixel size becomes very important. The smaller the pixel, the less light hits it, and the lower the DR you get. As an extreme example, look at a 10Mpixel and a 40Mpixel sensor.... The 10M sensor will have 4 times the light hitting each pixel, and as a result will have 2 stops better DR. HOWEVER, you can take the 40M image and resample it to 10M and end up with the same DR.

More pixels is a tradeoff between resolution and pixel quality, except with the greater resolution you can decide in post production if you want to keep the resolution, resample for quality, or a combination of the two. You have more total information.
You've got it backwards. The reason the 10 MP sensor has better dynamic range is because each photosite (a/k/a sensel or pixel well) with 4X the area also has 4X the full well capacity compared to a 40 MP sensor with photosites 1/4 as large. You can increase exposure so that the same number of photons are hitting a smaller sensel, but you can't increase the full well capacity so that it takes four times as many photons to reach full well capacity.

If areas in the higher resolution sensor with smaller sensels are fully saturated, resampling will not increase the DR.
 

Michael Clark

Now we see through a glass, darkly...
Apr 5, 2016
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The attraction of the 7D series was also the extra shooting range for motorsports, sports, airshows, birders etc. Also the high frame rate for capturing action.
With some of the RF rumours promising much longer reach lenses, the need for smaller sensors to get the reach goes away if the lenses are not too expensive.
And keeping the MegaPixels low means todays achievable frame rates can easily rise to capture the action.
But the lenses are more expensive at desired angles of view needed for field sports and apertures needed for artificial lighting.

Compare the EF 200mm f/2.8 on an APS-C camera to the EF 300mm f/2.8 on a FF camera: $750 vs. $6100.
Compare the EF 70-200mm f/2.8 L IS II/III to the current Sigma 120-300mm f/2.8 on a FF camera: $2100 vs. $3600.

Or compare the EF 300mm f/2.8 L IS II on an APS-C camera to the 400mm f/2.8 L IS II on a FF camera: $6100vs $10000
And there's no 450/500mm f/2.8 for any price.

The attraction of the APS-C 7D Mark II (or Nikon D500) was you got all of the following: pixel density needed for cropping, high frame rate, and better reach in a highly ruggedized body that wasn't matched by any FF camera other than the 1D series.

7D Mark II + EF 70-200mm f/2.8 L IS II cost (list over the past 3-4 years) $1700 + $2300 = $4000

1D X Mark II + EF 300mm f/2.8 cost (list over the past 3-4 years) $5500 + $6100 = $11600

None of Canon's 5 series bodies to date match the 10 fps of the 7D Mark II.
None of Canon's 5 series bodies to date match the 200,000 shutter rating of the 7D Mark II.
Even with the 30 MP 5D Mark IV, cropping to APS-C size leaves less than 12 MP.

At the time he tore down a 7D Mark II in early 2015, Roger Cicala said the 7D Mark II was the most weather sealed camera he had ever been inside of. The 1D X and 5D Mark III had both been on the market for almost three years at that point, so presumably Uncle Roger had seen their innards by then.

I think the reason both Canon and Nikon abandoned the concept was not because there is not enough market demand for them. It's because they realized how much camera they were selling for one-fourth the price of their FF sports bodies and also how much they assumed they were losing selling 70-200mm f/2.8 lenses instead of 300mm or 400mm f/2.8 lenses. What they fail to account for is that many 7D Mark II/D500 shooters using 70-200mm f/2.8 lenses wouldn't buy FF sports cameras and 300mm f/2.8 or 400mm f/2.8 lenses even if the APS-C option is not available. They either can't afford it, or aren't willing to pay that much for it.
 
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Kit.

EOR R
Apr 25, 2011
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You've got it backwards. The reason the 10 MP sensor has better dynamic range is because each photosite (a/k/a sensel or pixel well) with 4X the area also has 4X the full well capacity compared to a 40 MP sensor with photosites 1/4 as large. You can increase exposure so that the same number of photons are hitting a smaller sensel, but you can't increase the full well capacity so that it takes four times as many photons to reach full well capacity.

If areas in the higher resolution sensor with smaller sensels are fully saturated, resampling will not increase the DR.
The sum of 4 pixels has about the same effective full well capacity as one pixel 2x2 times bigger.
 

Don Haines

Beware of cats with laser eyes!
Jun 4, 2012
8,258
1,896
Canada
You've got it backwards. The reason the 10 MP sensor has better dynamic range is because each photosite (a/k/a sensel or pixel well) with 4X the area also has 4X the full well capacity compared to a 40 MP sensor with photosites 1/4 as large. You can increase exposure so that the same number of photons are hitting a smaller sensel, but you can't increase the full well capacity so that it takes four times as many photons to reach full well capacity.

If areas in the higher resolution sensor with smaller sensels are fully saturated, resampling will not increase the DR.
At any aperture, the density of the light is the same regardless of what camera, sensor, or format is used.
For the same scene, At F4 and 1/1000th second, the same number of photons will hit a square mm on any camera from any manufacture.

large photo sites will capture more photons than a smaller photo site . Smaller ones will have a greater sampling density. You have more total information in the denser sampling
 
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CanonFanBoy

O.K. Boomer
Jan 28, 2015
4,574
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Irving, Texas
At any aperture, the density of the light is the same regardless of what camera, sensor, or format is used.
For the same scene, At F4 and 1/1000th second, the same number of photons will hit a square mm on any camera from any manufacture.

large photo sites will capture more photons than a smaller photo site . Smaller ones will have a greater sampling density. You have more total information in the denser sampling
Doesn't this also mean that a FF crop as opposed to a crop sensor will have better low light performance? Because of the larger photo sites? Less sampling density, but greater light capturing ability? Of course, less megapixels.
 

Don Haines

Beware of cats with laser eyes!
Jun 4, 2012
8,258
1,896
Canada
Doesn't this also mean that a FF crop as opposed to a crop sensor will have better low light performance? Because of the larger photo sites? Less sampling density, but greater light capturing ability? Of course, less megapixels.
But on a FF crop, you are only using part of the sensor.

let’s say we have a crop camera and a FF sensor with a crop mode, same tech level for both

case 1, they both have the same total megapixel count, same lens, same camera settings, and lets say 20 megapixels (easy math)

on the two cameras, the same amount of light hits the 20Mpixels of the crop sensor as hits the central 8Mpixels of the FF sensor in crop mode. Each individual pixel in the FF sensor gets 2.5 times as many photons striking it, and it has a stop better DR..... but the crop sensor image can be resampled to get the same image as the FF sensor. The FF image has better pixels, but the crop has more. In this case the crop sensor is superior

case 2, the FF sensor is 50Mpixels and the crop is 20.

in this example, the results should be identical. The pixels are the same size, get hit by the same amount of photons, and all should be indistinguishabl.

case 3, (and the reason FF sensors are better), both cameras are the same pixel count.

you use the FF sensor in FF mode. You use a lens that is 1.6 times as long On the FF body.
the field of view is the same on both, but 2.5 times as many photons hit the FF sensor As the crop sensor. The FF sensor captures more information, the image is better.
 

AlanF

Canon 5DSR II
Aug 16, 2012
6,248
4,146
You've got it backwards. The reason the 10 MP sensor has better dynamic range is because each photosite (a/k/a sensel or pixel well) with 4X the area also has 4X the full well capacity compared to a 40 MP sensor with photosites 1/4 as large. You can increase exposure so that the same number of photons are hitting a smaller sensel, but you can't increase the full well capacity so that it takes four times as many photons to reach full well capacity.

If areas in the higher resolution sensor with smaller sensels are fully saturated, resampling will not increase the DR.
At any aperture, the density of the light is the same regardless of what camera, sensor, or format is used.
For the same scene, At F4 and 1/1000th second, the same number of photons will hit a square mm on any camera from any manufacture.

large photo sites will capture more photons than a smaller photo site . Smaller ones will have a greater sampling density. You have more total information in the denser sampling
What you say is quite correct. However, misunderstandings occur because dynamic range is measured for a print or a screen output of the sensor image enlarged to a defined size. For example, photonstophotos.net defines PDR as the dynamic range you would expect in an 8x10" print viewed at a distance of about arms length. Now, a 40 Mpx FF and a 10 Mpx FF sensor enlarged that way would indeed as you say have the same DR as argued by Kit as well. But, an APS-C sensor with the same number of photons per unit area from the same f-number and shutter speed needs to be enlarged by 1.6x1.6 times more so the noise is amplified more and the DR decreases accordingly.
 

usern4cr

I'm New Here
Sep 2, 2018
19
17
let’s say we have a crop camera and a FF sensor with a crop mode, same tech level for both

case 1, they both have the same total megapixel count, same lens, same camera settings, and lets say 20 megapixels (easy math)

on the two cameras, the same amount of light hits the 20Mpixels of the crop sensor as hits the central 8Mpixels of the FF sensor in crop mode. Each individual pixel in the FF sensor gets 2.5 times as many photons striking it, and it has a stop better DR..... but the crop sensor image can be resampled to get the same image as the FF sensor. The FF image has better pixels, but the crop has more. In this case the crop sensor is superior

case 2, the FF sensor is 50Mpixels and the crop is 20.

in this example, the results should be identical. The pixels are the same size, get hit by the same amount of photons, and all should be indistinguishabl.

case 3, (and the reason FF sensors are better), both cameras are the same pixel count.

you use the FF sensor in FF mode. You use a lens that is 1.6 times as long On the FF body.
the field of view is the same on both, but 2.5 times as many photons hit the FF sensor As the crop sensor. The FF sensor captures more information, the image is better.
case 1: You are correct until the last sentence. If you resample the crop sensor 20MP into 8MP (as you seem to indicate) you will result in an image that is slightly worse than the 8MP from the FF. If, instead, you resample the 8MP from the FF into 20MP then you will result in an image that is slightly worse than the 20MP from the crop sensor.

case 2: you are correct

case 3: If you only use a 1.6x longer lens on the FF then you will *not* get the same blurred image for the out-of-focus foreground & background. To get the same field of view & blurred image everywhere, you must also use a f/# which is 1.6x higher (eg 100mm f4 on crop sensor and 160 f6.4 on the FF). Then the entire FF sensor gets the same image as the entire crop sensor. They also have the same aperture for light gathering and thus both get the *same* total amount of light in their respective full sensors, but that amount of light is spread out thinner on the FF sensor versus the crop sensor. The crop sensor will reach full-well exposure before the FF sensor, which is why the FF sensor has better dynamic range. Furthermore, the FF lens (1.6x in focal length and f#) will be roughly the same size and weight as the crop sensor lens assuming you are shooting wide open on both.

But you have been discussing using a FF camera in "crop mode", which crops your display and the image stored, so the remaining pixels outside the center are lost. If the FF camera takes a full image and does the crop *afterwards*, such as in post, then you have the freedom to crop the smaller image either at the center or off-center to get the detail you happen to want at that time - which is a *huge* benefit when shooting a FF in normal mode and cropping later.

One final comment is that you can't always get the equivalent lens for a cropped camera as you have discussed here. Eg. a FF camera and 50mm f1.2 lense would be equivalent to a crop camera and 31mm f0.75 lense (assuming a 1.6 crop sensor camera). And I don't think you're going to find a 31mm f0.75 lens for it.
 
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SteveC

M6 mk II
Sep 3, 2019
481
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If you are using the full area of FF and APS-C crop and viewing the output of both at the same size, the FF at higher isos will always beat out a crop. And current sensors are so good that their efficiencies can't be improved enough for a future APS-C to have lower noise than a current FF. Which is not to say that current APS-Cs are not good, they are darned good and more than capable for most situations.
But he was distinctly NOT talking about using the full area of the FF sensor!
 
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Aussie shooter

@brett.guy.photography
Dec 6, 2016
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I am in a bit of same situation. I have a well functioning but also well used 6D, two top-of-line EF (L) Zooms and a handfull of good EF primes. My photography is a bit of everything - so I am glad for the size of the 6D. However - should i by a new camera now, I would go for the 5D mkIV. It will serve me for the next 5-7+ years, and by that time, the landscape for RF lenses and bodies would be clear and mature. I know that the reselling price for my old EF gear at that time will be lower - but I am not a "buy and sell" person. I buy my gear, an use it as long as i last.
For travel however - I see and idea for the future of R and RF - a bigger high-end pro body with large zooms and a smaller RP size body that can be used with an RF 24-105 f/4 and a 35mm for travel or street photography.

But for now, and for the next 10 years i think - I stay with EF cameras and lenses
OR......…...………… You can buy a mirrorless body and continue to use your EF lenses on it(with increased functionality and performance) until you are ready to buy into the RF lens lineup. Canon has given you (as they once said) a very elegant solution as far as transitioning goes.
 

Michael Clark

Now we see through a glass, darkly...
Apr 5, 2016
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The sum of 4 pixels has about the same effective full well capacity as one pixel 2x2 times bigger.
Yep. But all four smaller sensels do not necessarily all receive the same number of photons. Poisson distribution and all, not to mention edges between objects in the scene with different brightnesses.
 

Michael Clark

Now we see through a glass, darkly...
Apr 5, 2016
1,790
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At any aperture, the density of the light is the same regardless of what camera, sensor, or format is used.
For the same scene, At F4 and 1/1000th second, the same number of photons will hit a square mm on any camera from any manufacture.

large photo sites will capture more photons than a smaller photo site . Smaller ones will have a greater sampling density. You have more total information in the denser sampling
You also have greater randomness due to Poisson distribution.
 

Kit.

EOR R
Apr 25, 2011
1,682
1,016
Yep. But all four smaller sensels do not necessarily all receive the same number of photons. Poisson distribution and all, not to mention edges between objects in the scene with different brightnesses.
Doesn't that produce a "good" kind of nonlinearity, though? Looks like it should very slightly increase detail in highlights.