Hi all,

A friend & I are trying to make an informed decision and I would love to hear from some of my "trusted Hogs" to assist.

OK - here goes, we both currently own/use/love our Nikon D500's (crop sensor), and are considering adding a FF NIKON with the intention of improving low light performance at higher ISO's over our D500's. The ONLY models under consideration are the D850, D5, D6 , and Z9. The main reason for wanting to add a new camera is for better performance in low light. Our main subjects are birds, BIF, and wildlife. I'm fully aware of the limitations of mirrorless when it comes to what I shoot, as well as the specs on the cameras under consideration. The ONLY thing I'm asking about is low light performance. All our lenses are FX.

1) Which of the above cameras gives the best performance in low light at higher ISO's, and why? D5 & D6 (both FF) are significantly lower MP than the FF D850 and the Z9. Feel free to get technical!
2) If I were to use the D850 or the Z9 (both much higher MP than the D500, D5, and D6) in one of the crop modes, wouldn't the pixel DENSITY remain the same vs. the FX mode on that camera thus making NO difference in low light performance? If my understanding of pixel size/pixel density is correct, I would think that the low light performance of the D850 or the Z9 would remain the same FX mode vs Crop Mode in each camera.
3) Given my understanding, noted in 2) above, wouldn't the low light performance of the D5, D6 be better than that of the D850 or Z9 using one of the available crop modes? (I know that the D500 is a crop sensor, and therefore has higher pixel density than either the D5 or D6 that have about the same MP count as the D500, and therefore the D500 would NOT be as good in low light as the D5 or D6.)

I realize that the processors in the cameras under consideration differ, and that those differences may come into play when it comes to low light performance. Feel free to mention those differences if they make a difference. I'm not technically savvy enough to know the differences between processors.

After reading through this, it seems that my question has come down to the crop sensor D5 & D6 vs the FF D850 vs Z9.

Please feel free to correct any of my misunderstanding(s) of this subject.
Thanks in advance!

Hi all,

A friend & I are trying to make an informed decision and I would love to hear from some of my "trusted Hogs" to assist.

OK - here goes, we both currently own/use/love our Nikon D500's (crop sensor), and are considering adding a FF NIKON with the intention of improving low light performance at higher ISO's over our D500's. The ONLY models under consideration are the D850, D5, D6 , and Z9. The main reason for wanting to add a new camera is for better performance in low light. Our main subjects are birds, BIF, and wildlife. I'm fully aware of the limitations of mirrorless when it comes to what I shoot, as well as the specs on the cameras under consideration. The ONLY thing I'm asking about is low light performance. All our lenses are FX.

1) Which of the above cameras gives the best performance in low light at higher ISO's, and why? D5 & D6 (both FF) are significantly lower MP than the FF D850 and the Z9. Feel free to get technical!
2) If I were to use the D850 or the Z9 (both much higher MP than the D500, D5, and D6) in one of the crop modes, wouldn't the pixel DENSITY remain the same vs. the FX mode on that camera thus making NO difference in low light performance? If my understanding of pixel size/pixel density is correct, I would think that the low light performance of the D850 or the Z9 would remain the same FX mode vs Crop Mode in each camera.
3) Given my understanding, noted in 2) above, wouldn't the low light performance of the D5, D6 be better than that of the D850 or Z9 using one of the available crop modes? (I know that the D500 is a crop sensor, and therefore has higher pixel density than either the D5 or D6 that have about the same MP count as the D500, and therefore the D500 would NOT be as good in low light as the D5 or D6.)

I realize that the processors in the cameras under consideration differ, and that those differences may come into play when it comes to low light performance. Feel free to mention those differences if they make a difference. I'm not technically savvy enough to know the differences between processors.

After reading through this, it seems that my question has come down to the crop sensor D5 & D6 vs the FF D850 vs Z9.

Please feel free to correct any of my misunderstanding(s) of this subject.
Thanks in advance!

If you have a look at DXOmark and select "Nikon, Any Date" for a search you'll find the relevant data (by scrolling down). The value of most interest to you is in the "Sports" column since it indicates the low light, high ISO performance. The Z9 is too recent to be included but I believe its performance wasn't much different from the D850. The camera giving the best Sports figures is the Z6II (it is slightly better than the Z6 but they are both good). As you can see, the FF options are waaaay better than the D500.
I saw a recent video (can't remember who by) where they made the observation that if you compared contemporary sensors from the same camera manufacturer and compared hi-res sensors to the "standard" sensors (~20-24MP), the ISO noise was slightly worse with the hi-res sensor but it was also smaller due to the higher pixel count, and as a result it was less noticeable than the noise you got from lower res sensors. The video included side-by-side comparisons that were quite convincing. The worse noise of the hi-res sensor was noticeable only if you cropped or zoomed in on it, but with no crop or zooming the noise in the lower res image looked worse because it was bigger and therefore more noticeable, despite the fact that it was less pronounced when comparing pixel-to-pixel.

Obviously another difference was that the hi-res sensor provided more small detail, which helps image quality.

Other issues which I don't see in the prior answers (or reflected in your question) are whether you will be able to fill the sensor with your image (ie. will you have to crop) and the availability of the software to process the Z 9 images. I haven't done scientific tests but it appears to me that I was better off with my D500 then my Z 9 raws in low light, but I blame part of this on the fact that DxO and Topaz DeNoise haven't updated their software yet to handle the Z 9 raw files (both of which I would routinely use on my D500 images). And I am routinely cropping my images from the Z9 more than with the D500. I also think this is applicable to your question on why a D850 is better than a D500 in low light whereas the pixel density is very close. If the image on the D850 is cropped to that taken by a D500, I think the noise will be very similar.
If you are primarily concerned about shooting in low light, is it feasible to get faster lenses? For example, when I go out close to dusk, I try to use a f/2.8 lens and shoot with a tripod for longer exposures. Some low light images (ie. high ISO) with the D500:

I do not have a D850, D6, or Z9 so I can't really give you a comparison. I have a D4 and a D5.

The D5 handles high ISO better than the D4, but the advantage is really marginal. When the D6 came out I thought about it but, having retired, I don't shoot many events any more and the D6 specs looked to me to be really minor increments over the D5. Probably more in-camera image processing, since we're pretty close to the quantum limit in sensors.

I use my D4 for normal work and only use the D5 when (1) I really need high ISO or (2) I left my D4 at home or (3) it has the wrong lens on it for a quick shot (I tend to keep the D4 and D5 in my bag with different lenses to minimize lens swapping time).

In my opinion, the D4 is good to ISO 50K and the D5 to ISO 100K. That is for event shooting, where most of the shots are used for PR and are shown on websites or in newsletters, so there's a lot of downsampling going on before publication. When I had a D3, I tried some experiments. The D3 was good (for my purposes) to 25K, but I could get good shots (with a lot of post work) at 50K or even 100K, but only if I could have gotten the shot at 25K. Going to too high ISO led to color shifts that were difficult to deal with in post. I have not done the same level of experimentation with the D5.

I used the D4/D5 combo at my daughter's wedding last year but I limited the ISO to 10K-20K (reception, poor lighting).

Have you considered renting? Get the cameras you're most interested in and set up some test shots to see how they perform. You might not be able to do that in the wild with the BIF shots but maybe a frisbee? With a decor that will give you something to resolve?

If you are looking to compare cameras with different resolutions, you should be downsampling to the lowest common denominator - which is not the same as cropping. Downsampling (aka resampling to a lower resolution), preserves most of the detail of the hi res capture, and it will average out the noise among pixels - to provide a good basis for comparison.

Here is a technical description of how this happens, and it discusses 4 types of noise that are mitigated when downsampling

https://photographylife.com/why-downsampling-an-image-reduces-noise

If you are printing, there is no need to consider the D500 because it just can't compete with the other cameras you have mentioned - especially if you want to compare uncropped images. The reason being that an uncropped image from a D500 would have to be magnified considerably more to achieve the same print size - it is not so much about pixel density. But a 45 mp image resampled to 20.6 mp would likely be no noisier, and likely record more detail that will still be visible in the downsampled image.

As far as mirrorless cameras are concerned, the hybrid, high performance focusing systems are better than even what is in the D6 or the D850, and all three mfgrs - Sony Nikon and Canon have competing systems - and they are desirable over the DSLR - which, by comparison, is not as consistent and not as accurate due to the nature of phase detect AF systems.

You can talk yourself into or out of anything you want. My experience has been that the D500 doesn't hold a candle to even a D800 for birds, especially if you need to crop, and most of the time, even with a static subject you can never get close enough. First image below is a best view of a male cardinal with a D500 and a 28-300 (which a lot of people swear by, but I swear at). Second image is the same bird using a Sigma Sport on a D800, and as you can see there is no comparison. In marginal light it quickly goes downhill for the D500. Both images were hand held.

Third image was taken with 150-600 Sigma Sport also on a d800 hand held at 1/25 sec - zoomed to 600mm at around the minimum focus distance -

Fourth image is a crop of the third -

Fifth is a blackpoll warbler, D800, heavy crop, ISO 2000 - hand held

sixth and seventh are Sigma 150-600 Sport, hand held, ISO 12800, uncropped then heavy crop - all hand held.

The D850 and the Z9 will be a lot better, as long as you put a sharp lens - zoom or prime. I used to have a 600mm F4 AF-S II and it was very sharp, but it also weighed about 11.2 lbs, which was too heavy for hand holding. The Sigma Sport was the lens I selected as a replacement - so I would not give up any image quality and be able to hand hold it. The D810 is pretty decent at ISO 12800, but from what I've seen the D850 is even better. By association the Z9 should be at least as good. You can pretty much dismiss the D500 - it was ground breaking when it was released, but simply cannot complete with the big boys when the light sucks, or when you have to crop because you can't get close enough - which is 75% - 90% of the time.

My main bird and wildlife lenses are my Nikon 500mm PF and my Tamron 150-600 G2.

Thank you for posting your shots for comparison. Wow, what big differences! I'm beat right now and will take a deeper dive tomorrow. When I bought my D500 back in 2017, it was to trade up from my D7200. The big reason for upgrading back then was that I needed, not simply wanted, a much larger buffer. My D7200 would bog down at the worst possible times for a bird photographer.

You are definitely steering me in the right direction here. Thank you for sharing your professional opinion coupled with personal experience. BTW, I agree with you on the 28-300.