Why smaller sensors beat full-frame sensors for wildlife photography

[Braineack]

but: the step size from 400mm to 800mm might be from $1,000 to $20,000. Plus the lenses weigh a ton.

keep the 400mm lens, shoot 4/3rds. However, IMHO, the image shot with $20,000 long fast glass on large sensors are superior images.

 

[Soocom1]

Aspect Ratio.
There is plenty on it.

No I am not fired up, its simply that the argument that a "better" photo is made with a smaller sensor is at least to my experience, a non issue.

When you are dealing with the high levels of cropping that occur in most people's wildlife photographs, you can bet that it is an issue. One can increase resolution or buy a bigger lens. Increasing the lens size is ideal—but: the step size from 400mm to 800mm might be from $1,000 to $20,000. Plus the lenses weigh a ton.

Again, I think you have no idea what the issues are in wildlife photography.

OK...
Look.

35mm is 1.5-1.6 times larger than APS. (Nikon and Canon respectively)
Both 35mm and APS shoot an aspect ration of 3:2.

There is distortion in all lenses that the further to the edge you get in any lens the more distorted things become.

The further from the center you go there is distortion and a form of "skewing" where things elongate from the lens aspects. This simply cannot be eliminated. It can be minimized.

When you are trying to compose an image of say a bird in flight, and your shooting 35mm, while framing the image as close to center as possible, there is going to be an amount outside the center that will regardless of equipment used, get the skewing going on.
So if you frame the image in the FF sensor to the equivalent of an APS sensor, the image in the 35 (FF) image is less distorted and ergo when the final print comes out is closer in actual proportions than the APS.

In an APS sensor, that same image is more greatly distorted. Ergo, the wings if compared (if possible) would not look quite the same as in the 35mm regardless of the cropping.

The pixle size becomes irrelevant because the distortion factor in relation to sensor (format size) takes the game.

When I talk about projection, it is a factor found in cartography.
The further from the center you get, the more distortion takes place because in projection, your representing a 3D object in 2 dimensions. This same effect is occurring in photography because your trying to capture a 3D object into a 2D plain.

So distortion will exist regardless. One simply does not see that distortion unless one were to shoot the exact same object with diff. format sizes.

 

[freixas]

but: the step size from 400mm to 800mm might be from $1,000 to $20,000. Plus the lenses weigh a ton.

keep the 400mm lens, shoot 4/3rds. However, IMHO, the image shot with $20,000 long fast glass on large sensors are superior images.

In the Canon line, it would be APS-C vs full-frame, at least with the cameras I'm most familiar with. I agree with both sentiments. I was considering a full-frame camera, but decided to upgrade within the APS-C family. I don't see a lot of advantage in using a full-frame sensor for most bird photography, which is the point of my post.

The $20,000 lens will generate a better image, but I can't afford one. If it's fast glass (picture an f/2.8 800mm!) it might be too heavy to carry, which can limit photo opportunities. I've seen wildlife photographers using assistants just to carry the tripod to hold their super-duper telephoto. I'm thinking of upgrading to a 600mm, 6 lb lens, but I might try carrying the weight first to see how it feels.

To be clear, if you have a $20,000 lens, my post would compare an APS-C (or 4/3rds or whatever) camera to a full-frame camera , with both cameras using the same $20,000 lens. Of course, if you are close enough to a bird (or have enough zoom) to fill a full-size sensor, the larger sensor wins. That happy circumstance doesn't often happen.

 

[freixas]

Aspect Ratio.
There is plenty on it.

No I am not fired up, its simply that the argument that a "better" photo is made with a smaller sensor is at least to my experience, a non issue.

When you are dealing with the high levels of cropping that occur in most people's wildlife photographs, you can bet that it is an issue. One can increase resolution or buy a bigger lens. Increasing the lens size is ideal—but: the step size from 400mm to 800mm might be from $1,000 to $20,000. Plus the lenses weigh a ton.

Again, I think you have no idea what the issues are in wildlife photography.

OK...
Look.

35mm is 1.5-1.6 times larger than APS. (Nikon and Canon respectively)
Both 35mm and APS shoot an aspect ration of 3:2.

There is distortion in all lenses that the further to the edge you get in any lens the more distorted things become.

The further from the center you go there is distortion and a form of "skewing" where things elongate from the lens aspects. This simply cannot be eliminated. It can be minimized.

When you are trying to compose an image of say a bird in flight, and your shooting 35mm, while framing the image as close to center as possible, there is going to be an amount outside the center that will regardless of equipment used, get the skewing going on.
So if you frame the image in the FF sensor to the equivalent of an APS sensor, the image in the 35 (FF) image is less distorted and ergo when the final print comes out is closer in actual proportions than the APS.

In an APS sensor, that same image is more greatly distorted. Ergo, the wings if compared (if possible) would not look quite the same as in the 35mm regardless of the cropping.

The pixle size becomes irrelevant because the distortion factor in relation to sensor (format size) takes the game.

When I talk about projection, it is a factor found in cartography.
The further from the center you get, the more distortion takes place because in projection, your representing a 3D object in 2 dimensions. This same effect is occurring in photography because your trying to capture a 3D object into a 2D plain.

So distortion will exist regardless. One simply does not see that distortion unless one were to shoot the exact same object with diff. format sizes.

You need to re-think this. Let's say you shoot a bird in flight with an APS-C sensor and a full-frame sensor, both using the same lens. You rarely fill the APS-C sensor with the bird, so let's say the bird fits within a 3mm x 3mm box in the center of either sensor. You are using the exact same lens and lens mount, so there is zero difference between the image of the bird in either camera. Skewing will be exactly the same.

If you are using the same lens and expect the images to be in focus, the distance from the lens to the sensor needs to be constant regardless of the sensor size. I think you are confusing this will having the bird occupy the same percentage of the frame. This is impossible when using the same lens (and same focal length, of course). A 400mm lens doesn't know a thing about the size of the sensor that the image will fall on.

Also the "non issue" you mention is a real issue when you go to pay for a camera. An 80D might run $850 (APS-C) vs. $2,000 for a 7D Mark IV (full-frame) that won't actually perform as well for bird photos. If you are rich, maybe it might be a non-issue.

 

[freixas]

What about defraction at smaller f stops the more smaller pixels the more spillover as I understand it

Hmmm... Interesting. I'll have to look into this. Thanks for the comment.

 

[Soocom1]

You need to re-think this. Let's say you shoot a bird in flight with an APS-C sensor and a full-frame sensor, both using the same lens. You rarely fill the APS-C sensor with the bird, so let's say the bird fits within a 3mm x 3mm box in the center of either sensor. You are using the exact same lens and lens mount, so there is zero difference between the image of the bird in either camera. Skewing will be exactly the same. If you are using the same lens and expect the images to be in focus, the distance from the lens to the sensor needs to be constant regardless of the sensor size. I think you are confusing this will having the bird occupy the same percentage of the frame. This is impossible when using the same lens (and same focal length, of course). A 400mm lens doesn't know a thing about the size of the sensor that the image will fall on.

Also the "non issue" you mention is a real issue when you go to pay for a camera. An 80D might run $850 (APS-C) vs. $2,000 for a 7D Mark IV (full-frame) that won't actually perform as well for bird photos. If you are rich, maybe it might be a non-issue.

Actually, because I have played this game with 35mm v. Med. Format, there is HUGE difference.

The premise of the argument is based on the scientific minutiae of pixle size to that of format size.
Its academic because the format size is the real determining factor.
35mm v. APS is not particularly wide. So the amount of distortion is minimal in comparison overall, but it is still there. 1.5 to 1.6 for FF v. APS.

4 TIMES for 35 to Med. Format.

"You are using the exact same lens and lens mount, so there is zero difference between the image of the bird in either camera. "

Actually there will be because of format size. Not pixle count.

 

[Derrel]

In the real world a typical two camera setup for top wildlife shooters today is the Nikon D850 and the Nikon D500, And while the Nikon D500 is a good camera, to me I personally think that the 850 shots tend to look better

A few years ago several members here compared Their D800's which is 36MP to their D 7200 . As I recall, in all cases the cropped-down D800
files typically looked just a little bit better than the D 7200 photos.

On the Nikon side, the high-end cameras for over 10 years have offered smaller than full sensor captures. For example in 2005 I bought the Nikon D2X which offered a 12 megapixel 1.5 DX sensor,as well as a 2.0 8.2 frames per second high-speed crop mode. In 24 x 36 mm or FX format cameras, Nikon has long offered would it calls the DX crop mode

 

[Soocom1]

If its any consolation, your also talking to someone who is going to mount a mirrorless APS camera to a Large Format camera.

Thats the kind of goof ball things I do.

 

[Derrel]

in effect Nikon offers a really good full frame camera and a really good crop frame camera in the D850. Well I am not exactly sure, I believe the 36 megapixel D 800 offered a 16.3 megapixel crop frame capture option, which is not as many pixels as the then current 24 megapixel DX models.

 

[Derrel]

Sometimes theory and practice diverge.

 

[Braineack]

Let's say you shoot a bird in flight with an APS-C sensor and a full-frame sensor, both using the same lens. You rarely fill the APS-C sensor with the bird, so let's say the bird fits within a 3mm x 3mm box in the center of either sensor. You are using the exact same lens and lens mount, so there is zero difference between the image of the bird in either camera. Skewing will be exactly the same.

Disagree!

Using the same lens on the APS-C sensor vs. the FF sensor, all other things being equal, if I can fill the frame with a bird with the APC, the bird will NOT fill the frame on the FF sensor. The images will look different, the FF image will appear further away since the bird will be smaller.

Why would someone using an APS-C sensor "rarely fill the frame"? It's EASIER to fill the frame using the smaller sensor since it has more length at every given focal length -- all things being equal.

 

[freixas]

Let's say you shoot a bird in flight with an APS-C sensor and a full-frame sensor, both using the same lens. You rarely fill the APS-C sensor with the bird, so let's say the bird fits within a 3mm x 3mm box in the center of either sensor. You are using the exact same lens and lens mount, so there is zero difference between the image of the bird in either camera. Skewing will be exactly the same.

Disagree!

Using the same lens on the APS-C sensor vs. the FF sensor, all other things being equal, if the I fill the frame with a bird with the APC, the bird will NOT fill the frame on the FF sensor. The images will look different, the FF image will appear further away since the bird will be smaller.

Why would someone using an APS-C sensor "rarely fill the frame"? It's EASIER to fill the frame using the smaller sensor since it has more length at every given focal length -- all things being equal.

Actually, we are in agreement. I'm not sure what you think I said, but it is not what I said.

I said "You rarely fill the APS-C sensor with the bird". I and many of my bird photographer friends would consider it a lucky day indeed to fill an APS-C frame with a bird. One friend raved about getting a bird at about 80% of the frame. I would also be thrilled.

Regarding "the bird will NOT fill the frame on the FF sensor"—I never claimed it would. In fact, I said the image would fill a 3mm x 3mm box on both sensors. Since a full-frame is 35 mm x 24 mm and APS-C is 24.89 mm × 18.66 mm, a 3mm x 3mm image would be a smaller percentage of a full-frame sensor. So we are in agreement and I am puzzled as to why you thought otherwise.

 

[freixas]

So the amount of distortion is minimal in comparison overall, but it is still there. 1.5 to 1.6 for FF v. APS

There is no (zero) difference. Again, the lens has no idea what size sensor it will project on. Format size only matters when you can't fit the entire image of interest (a bird) onto the sensor. A lens that projects a bird as 3 mm x 3 mm on the sensor surface will project the bird identically on sensors of any size. Unless the sensor is smaller than 3mm x 3mm, the sensor size matters not at all. Any distortion caused by the lens will be identical within this 3mm x 3mm area.

 

[Braineack]

I see what youre saying now, read it wrong.

 

[Soocom1]

So the amount of distortion is minimal in comparison overall, but it is still there. 1.5 to 1.6 for FF v. APS

There is no (zero) difference. Again, the lens has no idea what size sensor it will project on. Format size only matters when you can't fit the entire image of interest (a bird) onto the sensor. A lens that projects a bird as 3 mm x 3 mm on the sensor surface will project the bird identically on sensors of any size. Unless the sensor is smaller than 3mm x 3mm, the sensor size matters not at all. Any distortion caused by the lens will be identical within this 3mm x 3mm area.

Again, wrong.

The lens is a lens is a lens.
That is quite true.
The FORMAT SIZE is what matters in the argument,
But as I said before, the format size is irrelevant if the photographer knows what they are doing.


It will project the same exact SIZE (all thing being equal) but the distortion will vary between the two and the image itself will be far different.