EOS R5 Mark II In what way does higher a higher resolution sensor impact image quality?

[kudro]

Let’s say I’m not planning on printing on large paper or further cropping. Would using and R5ii, for example, in crop mode image quality be noticeably different than using a similar quality lens that with a 1.6 times larger focal length?

For example, does software use those extra pixels to reduce noise or otherwise improve final image quality?

[kvbarkley]

The longer lens will have a lot more resolution and much better quality, and you won’t leave unused pixels on the table to coin a phrase

[SignifDigits]

Most people lean towards "more is better".  That may or may not be true in real-world situations.  I don't write algorithms for noise reduction, but I have worked in other optical ray tracing and optical simulations.  In those resolving around more actual data points always result in a more accurate final answer.  I assume that would be the case for noise reduction. But will that increased accuracy be "noticeably different"?  Maybe.

"Noticeably different" in your question does not lend it self to an objective accurate answer.  The same with "large paper".  If one lived with only 3x5 photos all their life, they might think 4x6 was "large paper", for instance.   For myself I do not consider bordered 8x10 "large paper"

Looking at a 4K 27" monitor versus a 32" monitor vs a 83" monitor would be different pixels sizes for each, and each person, depending upon their vision, might or might not be able to see a single white pixel on a black field, depending upon their distance from the screen, ambient lighting and screen contrast ratio even though the pixel would be larger and more readily apparent on the 83" screen. 

And most calculations are made for persons with 20/20 vision no astigmatisms and 120 degree of view.  Typically photographic output is not in a 120 degree field of view format.

If you final output is presented as an online screen photo in 1080P APC-S vs Full Frame would likely be unnoticeable.  Same thing with most video frames.

The fact is that most APS-C sensors and smaller (phones) produce acceptable images for most of our real world applications.   Most of the 4K video produced is from APS-C sensors.  That said, the best light sensitivity, color depth and dynamic range is obtained by larger sensors (1" and larger).  The difference in quality is noticeable on a 66" OLED 4K screen.

Native lens focal length is almost always preferable over crop sensor extensions, largely due to quality considerations.  Is it "noticeably different"?  To those that pixel peep and can truly see these nuances on their screens or color match and spend time calibrating screens and color matching it seems likely, yes.  For conversion to JPG to text around, definitely not.  Scenarios in between those two - maybe.

Long answer to a simple question.  Why don't you try it for yourself and decide for yourself and your situation and let us know what you decide?

[Waddizzle]

“ EOS R5 Mark II In what way does a higher resolution sensor impact image quality? “

Sensor resolution doesn’t improve image quality. A camera is a recording device that captures the image presented to it by the lens in front of it. 

If the lens is capable of high resolving power, then a high resolution sensor can capture more detail. A lower resolution sensor will capture less detail.

A lens with moderate resolving power used with a high resolution sensor probably won’t produce higher detailed images than a lower resolution sensor. In fact, images from the higher resolution sensor may seem softer than images from the lower resolution sensor.

The primary factor that determines image quality is the lens, not the sensor. 

[ebiggs1]

"The primary factor that determines image quality is the lens, not the sensor."

I agree with that statement but only to a degree. All things being equal the higher resolution sensor and the higher resolution lens will produce a sharper image. Using the same gear and reducing one or the other the image sharpness will suffer.

"A camera is a recording device that captures the image presented ..."

Also agree, however, there again though, it depends on what you are comparing if you take this to extreme you can see the point. If I am using my 1D, a 4.5 MP, camera VS my 1DX, an 18 MP, camera using the same lens the 1DX will make sharper images.

"...does software use those extra pixels to reduce noise or otherwise improve final image quality?"

Again, not a cut and dry answer but it is possible for editors like Photoshop to recover more info if it has more data to work with. That is the fundamental reason for shooting raw. You should always shoot raw file format.

"I’m not planning on printing on large paper or further cropping."

And the last part of the equation, how is the finished product going to be used. How its used may make all the above a moot point. For instance it doesn't take much photography power to put a picture on Facebook.

[ebiggs1]

"...does software use those extra pixels to reduce noise or otherwise improve final image quality?"

Again, not a cut and dry answer but it is possible for editors like Photoshop to recover more info if it has more data to work with. That is the fundamental reason for shooting raw. You should always shoot raw file format.

"I’m not planning on printing on large paper or further cropping."

And the last part of the equation, how is the finished product going to be used. How its used may make all the above a moot point. For instance it doesn't take much photography power to put a picture on Facebook.

[ebiggs1]

"Native lens focal length is almost always preferable over crop sensor extensions, largely due to quality considerations."

I don't understand where you are going with that. Native FL is the same whether you use it on a FF sensor or you use it on a crop sensor. The sensor or its size has nothing to do with it or does it change the native FL of a lens.

[March411]

I stayed away from this one, on other Canon sites this always turns into a fairly heated "discussion".

But for what it's worth I think ebiggs gave some great examples of why it not clear cut and frequently debated. I would lean into Ernie's camp. 

[jrhoffman75]

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@kudro wrote:

Let’s say I’m not planning on printing on large paper or further cropping. Would using and R5ii, for example, in crop mode image quality be noticeably different than using a similar quality lens that with a 1.6 times larger focal length?

For example, does software use those extra pixels to reduce noise or otherwise improve final image quality?

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If I understand your question correctly you are asking: "If I use a 100mm lens and select crop mode would the image quality be different than if I used a 160mm lens (based on the 1.6 crop factor) and used the full sensor area?"

Answer would be yes because when you select the crop mode you reduce the image size from ~45 megapixels to ~17 megapixels.

This is different than using APS-C crop sensor camera, where the 100mm lens would produce a field of view equivalent to a 160mm lens but cover the full sensor.

[ebiggs1]

"Answer would be yes because when you select the crop mode you reduce the image size from ~45 megapixels to ~17 megapixels."

I am not sure that is true, of course it technically decreases the total pixel count. The resolution remains the same on the sensor for the selected area. It also uses the center of the sensor which is also using the center of the lens. I am speaking without personal knowledge, I know doesn't stop a lot of folks form chiming in, but I am just using personal experience with photography in general. A smaller overall size of an image doesn't necessarily mean it is less sharp.

[shadowsports]

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@March411 wrote:

I stayed away from this one, on other Canon sites this always turns into a fairly heated "discussion".

But for what it's worth I think ebiggs gave some great examples of why it not clear cut and frequently debated. I would lean into Ernie's camp. 

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Marc,

I as well.  

The OP has or had a 5D mkIV last year.  July time frame.  He was contemplating mirrorless.  Not sure if you made the jump.