topic Re: EOS R5 Mark II In what way does higher a higher resolution sensor impact image quality? in EOS DSLR & Mirrorless Cameras

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

kudro — Sat, 31 Jan 2026 23:11:19 GMT

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?

Re: In what way does higher a higher resolution sensor impact image quality?

kvbarkley — Sat, 31 Jan 2026 21:22:50 GMT

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

Re: In what way does higher a higher resolution sensor impact image quality?

SignifDigits — Sat, 31 Jan 2026 22:41:37 GMT

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?

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

Waddizzle — Sun, 01 Feb 2026 00:19:48 GMT

“ 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.

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

ebiggs1 — Sun, 01 Feb 2026 16:03:37 GMT

"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.

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

ebiggs1 — Sun, 01 Feb 2026 16:10:08 GMT

"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.

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

March411 — Sun, 01 Feb 2026 17:38:51 GMT

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.

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

jrhoffman75 — Sun, 01 Feb 2026 20:53:40 GMT

@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?

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.

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

ebiggs1 — Mon, 02 Feb 2026 15:19:55 GMT

"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.

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

shadowsports — Mon, 02 Feb 2026 15:24:24 GMT

@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.

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.

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

SignifDigits — Mon, 02 Feb 2026 17:21:45 GMT

@ebiggs1 "Native focal length..." was meant to imply effective focal length for the sensor, not lens focal length. A 125mm lens would have an effective focal length of 200mm using a 1.6 crop factor. Given the discussion about number of pixels I believed that that was what the OP was asking about. Thus, if we compared a 70-200mm lens at f/4 at 125mm using sensor cropping on the R5 Mark II versus 200mm lens at f/4 at 200mm using the full sensor the "Native" (versus effective) focal length would, all other things being equal (assuming that neither 125mm nor 200mm were especially distorted, for instance) would provide more data in the image and a better quality final result should be possible.

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

jrhoffman75 — Mon, 02 Feb 2026 17:55:54 GMT

@ebiggs1 wrote:

"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.

The crop mode on a full frame R-series body is no different than shooting in full frame on any camera and then cropping in post to enlarge the subject. Using a longer lens would always be preferable to cropping.

If one is happy with the resulting image quality after discarding ~60 percent of the pixels versus using a 1.6 times longer lens then that is fine for them.

The purpose of the crop mode is to allow RF-S (and EF-S w/adapter) lenses to be used on full frame R-series bodies; something that is not possible on EF DSLRs. It is entirely different than using a crop sensor R-series camera.

Re: In what way does higher a higher resolution sensor impact image quality?

LeeP — Mon, 02 Feb 2026 21:37:00 GMT

That was a long reply, but it was very well done and wonderfully nuanced. I really enjoyed the master class feel of the commentary. I liked your comment about 8x10 not being large and I agree. I compete in photography and usually do an 8x12. That isn't large. At that scale, no one could tell whether the image was shot by my R100, R8, my Pentax 17, or any of my 35mm SLRs.

Re: In what way does higher a higher resolution sensor impact image quality?

SignifDigits — Mon, 02 Feb 2026 21:44:10 GMT

@ LeeP Thanks for the positive feedback. I just hope we're helping the OP as it seems we haven't heard back from them.

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

ebiggs1 — Tue, 03 Feb 2026 15:53:11 GMT

"Using a longer lens would always be preferable to cropping. "

That is a debat that doesn't seem to have an answer and will likly alway be a hot topic.

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

ebiggs1 — Tue, 03 Feb 2026 15:57:45 GMT

"If one is happy with the resulting image quality after discarding ~60 percent of the pixels ..."

Except the pixels were never there so nothing is discarded. Is it any different then using a normal crop camera with with around 25 MP? (too early for math)

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

ebiggs1 — Tue, 03 Feb 2026 16:09:19 GMT

"if we compared a 70-200mm lens at f/4 at 125mm using sensor cropping on the R5 Mark II versus 200mm lens at f/4 at 200mm using the full sensor the "Native" (versus effective) focal length would, all other things being equal (assuming that neither 125mm nor 200mm were especially distorted, for instance) would provide more data in the image and a better quality final result should be possible."

I am not exactly sure what you are trying to point out. It is not the lens that changes even though you have the 1.6 crop factor. It is the sensor that is the difference. Both of these lenses are native FL in either case. The 70-200mm at 125mm@f4 remains exactly what it is, a 125mm lens @f4 as well as the 200mm.

Or, do you mean comparing what the image will look like if somebody was to use a 125mm lens on a cropper and then used a 200mm lens on a FF? You contend the 200mm on the FF will produce the better image? Of course you know with all the possible variables that is impossible to prove or disprove.

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

ebiggs1 — Tue, 03 Feb 2026 16:12:40 GMT

SignifDigits, I love these kind of thought experiments. 😁

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

SignifDigits — Tue, 03 Feb 2026 21:38:40 GMT

@ebiggs1. I'm glad to hear that. Again, recall the OP asked about the R5 Mark II in cropped mode, thus using fewer pixels, and a "better quality final result should be possible." via a 200mm lens on the whole full-frame sensor versus effective 200mm via a 125mm focal length in cropped mode. I think in all cases I would, given the choice, prefer to shoot at 200mm native over the full-frame sensor rather than at 125mm in cropped mode. I think this was the point of their question.

I was not discussing a full frame sensor using a 200mm lens versus a comparable-number-of-pixels APS-C sensor using a 125mm lens with effective focal length of 200mm.

The only scientific statement that I know that could be made in that case is that the full-frame sensor pixels should gather more photons/light particles due to their larger physical size. Arguing whether that will mean anything regarding a large image printed at 300dpi or viewed on an 4k or 6K monitor isn't something that is of interest to me personally. To me it would be like arguing how many angels can fit on the head of a pin. In general think sharpness fixation is overrated. Give me a great artistic or human emotion piece over sharpness any day of the week. Not that I can produce any of the above personally - just my preference, and, of course. I would love to have all of my images tack-sharp and often publicly bemoan my ineptitude at being skilled enough to get them sharp AND amazingly artistic.

Steve McCurry’s 1985 portrait of the green-eyed "Afghan Girl" (Sharbat Gula) was sharp, but even if it hadn't been quite as sharp I feel confident it would have still made the cover. There are lots of iconic shots that were not all that sharp. Of course there was real film grain in many of them, too.

I got very amused as I recently purchased a 4K HDR Top Gun DVD. Original 1986 cut, not digitally remastered. One of the negative comments that I noticed when I bought it was that it was "grainy". I almost fell out of my chair laughing. Of COURSE it was grainy - it was shot on real film!!! ALL films from that era were grainy! And TVs in the US were all NTSC. Somehow we all managed to enjoy films, magazines, and get addicted to TV shows and sports.

Sorry to digress. I hope the OP got the answer they were after in all of this.

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

March411 — Tue, 03 Feb 2026 22:32:06 GMT

The mechanics of putting a full-frame sensor into crop tells/commands the camera to use and process data from the center portion of the imaging sensor which parallels the size of the smaller APS-C format but, again, it is using prime real estate, the center of the sensor. The sensors pixel size/density does not change; the amount/size of the sensor you are using changes and therefore the clarity of the image is not impacted.

Most lenses today, the sharpest spot is the center of the lens. Using crop technically would improve the image as it reduces soft edges, in some lenses vignetting and distortion that that can be a challenge in/on some lenses.

By using crop, only the number of sensors used to achieve the size/dimensions of the crop change to capture the image they are not altered, they capture the same light regardless of lens. Resolution is defined by the sensor, not the lens. And not I didn’t state sharpness but resolution.

Resolution measures the amount of detail an imaging system (camera, screen) can capture or display, typically defined by pixel count or lines of resolution. Sharpness describes the perceived clarity and edge contrast in an image. High resolution enables detail, while sharpness highlights the transitions between those details.

All that being said, the old adage garbage in garbage out applies, use a poor-quality lens and chances are probable you get a poor-quality image.

If you are going to print and using crop, that is a completely different conversation. Your composition becomes more critical and sloppy framing can create the need to crop the image further reducing the ability to print larger images. Larger format prints will be a challenge.