I'm 70 and at this point in my life I am fortunate that I can still hand hold my long lens for birds and wildlife. Optical stabilization, and the ability to shoot at high ISO thanks to some of the new software out there (I use DXO Prime and On1 NoNoise), makes it possible to shoot using F7.1 or F8, 1/1000 sec or faster and still get decent detail in my images.

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 shot of a male cardinal with a D500 and a 28-300 (which a lot of people swear by, but I swear at, but the softness in this case is not caused by the lens - the camera lacks the necessary resolution).

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.

Good morning, Jules. If I recall, you capture your images as JPEGs and then do some post processing on them. If that's still correct, then here's what I do and what I suggest.

Perceptible noise, whether in a photograph, an audio signal, or a radio signal, almost always arises when we try to add something to a signal that isn't there to start with. This can be contrast, sharpness, color saturation, or other properties of a photograph. Your camera offers you a significant ability to adjust these parameters, along with two or three others, in your captured JPEGs. Additionally, there are are several Picture Controls available, ranging from Flat to Vivid, and including several in between.

When you look at the individual sliders controlling these choices, they are labelled in a manner that seems to indicate that there is a "Normal," or "0" position in the middle of the scale, and the option to subtract from that by moving to the left, or add to it by moving to the right. This is a very unfortunate mis-labelling of these sliders, and has led many folks astray in their use. In fact, setting them all the way to the right does not "add" one whit of information to what was captured by the sensor. It simply displays the full amount to you. So since your images are generally well-saturated with fairly high contrast, I'd set those sliders all the way to the right in your camera. That way, you are never adding noise when you add these back in during processing. Reducing them, if necessary, is a totally non-destructive operation.

The same principle is true of White Balance. Capturing white balance correctly and under your own control is always preferable from a noise standpoint to coming back later and adding either blue or red back in to your image. Noise will always increase when you add something later.

Finally, it all starts with getting the exposure correct. Underexposure will always result in noise when bringing levels back up to where they should have started. And remember...when you are shooting at high ISOs, dynamic range is just limited. At ISO 12,800, the D500 has about 4.2 stops of dynamic range. The D850 is 4.9 stops, and the D6 is 5.2 (a D300 is 4.2 stops at ISO 4,000.) None of these is more than about half the range of silver-based monochrome photographic print paper. That doesn't leave much to give away, and it also doesn't leave any to be recovered when editing a raw file, for any of those three cameras.

There is no question that this is a tough environment. But it's a tough environment for any camera. I have found that best results depend on getting everything right. So far no real shortcuts, even with the D850.

Gene, I have to say that I do own Nikons D5, D850, D750, D500, and I just received my Z9 2 weeks ago. I have never really had a noise issue with my D500 and when Noise has Crept in I use Topaz DeNoise AI. I get great images from all of my Bodies, but I know when I have to use a certain one. I don't understand how anyone can say that the D500 lacks resolution. If I have to shoot a Michigan Football game, which I shoot every game, if it's a Night game then my D5 takes most of the use. Since I work at The University of Michigan in the Athletic Dept. I will always have my 600mm f/4 attached to my D850, my 500mm f/4 is on my D5, and I keep my 400mm f/2.8 on my D500. I always try to be prepared for something that might go off kilter, so to speak, because I have always lived by the mantra of expecting something to happen. If I were the OP I would tell him to jump on the D850 or the Z9. Let me know what you think.

Well you have to look at the first of the cardinal images taken with a D500 - noisy, even in decent light, and not very crop-able - like the images taken with the D800.

I've used (never owned) a D500 and a D850 and could never justify purchasing a D500, but really enjoyed everything about the D850. I still use a D800 and a D810 - and considering mirrorless down the road - but I am retired, so there is no rush. In proper context, I used to get great images with my 10mp D200. But does it compare with a printed image from a D500 - not a chance. I feel the same way about the D500 vs a D4/D5/D6/D800/D810/D850 - its a fine camera, but can't do what the others can do in poor light or when cropping is necessary. When uncropped, small birds can be photographed with good quality - see the blue jay below taken with a D500. But how often can one get that close to a wild bird without spooking it?

If I were the OP, I would jump on either the D850 or the Z9 - both are exceptional cameras.

This will probably sound like an obtuse answer to your question. It is not intended as such. But in my experience, the biggest source of noise in photographs occurs when something is added to an image..."brightness," saturation, contrast, etc. I have never noted that "subtracting" has added noise. Correcting white balance involves adding a color bias to make it more correct. Pulling an image out of the shadows adds brightness, as does increasing contrast. Since Jules works with JPEGs (or at least he used to), reducing something and then adding it back in later doesn't seem to be a good strategy for minimizing noise. I have found that it is not for me when working with JPEGs.

Most picture controls do not change a raw capture. But correct exposure certainly does. And I am not convinced that white balance does not.

As far as White Balance goes...there's just too much likelihood that AWB will make a genuine mess of things. I am sitting right now in a classroom with light green walls and plight green carpet squares. Since AWB works by trying to "stack" the three histograms on top of each other, there is no way that any green object is going to appear properly colored in an image exposed with it turned on. The system is going to adjust out the preponderance of green in any image, taking with it the green in that object and anything else, including the walls and floor, leaving them gray and everything else with a purple cast. (I know that is the "Tint" axis, but it will still happen.)

The final factor here is that these cameras all have internal tools to manage noise and reduce it in the final image...High ISO Noise reduction as well as Long Exposure Noise Reduction. These both work well when used properly. The question becomes whether it is feasible to use them. Long Exposure NR works by taking an additional exposure without opening the shutter, then subtracting anything recorded from the first exposure. It effectively eliminates hot pixels, but at a cost of time. Probably not feasible for Jules. High ISO NR can reduce sharpness slightly. This may or may not be a problem.

My point is that there is a lot that can be done to reduce noise and improve quality from the start. I find that very few folks are aware of this, and just accept what they get. Similarly, Nikon cameras for some reason are shipped with very poor Picture Control setups. Most folks just accept that as well, then complain about the poor quality of images. And it is all made worse by choosing image formats with very low resolution and/or very high ratios of compression. Until all of that is fixed, it's not justified to complain.