I was looking back at some photos from a past vacation—one where I rented a Nikon D500 to bring along with me—and I noticed that I had taken some photos set to really high ISO numbers. For example, this photo of these lanterns was shot with an ISO just over 17000!
This is a screenshot of a crop of the original photo, so there’s a little more in the frame than shown here.
Unless it's very specific for the look of the photo, I typically set the ISO to use AUTO-ISO, which essentially lets the camera decide what ISO setting is best for the shot. Nikon lets you set a base setting and a maximum setting, however, for the D500 I don't think I had set it to a specific maximum ISO, because in my library I saw shots that went all the way up to 40000.
When I got my current camera, the Nikon Z 7ii, I had left on a lot of the noise reduction settings (that blur out the noise in camera) and I had set the maximum AUTO-ISO for each of my three user settings to go no higher than 2000 or 4000.
I've noticed that when taking photos in situations where I'd expect the ISO to go way up that one of two things happen. Either the noise reduction does its thing and the image looks a little blurry, or if in a situation where I'm shooting Aperture Priority (where the shutter speed is automatically set to work with a fixed aperture setting) the shutter speed goes so low that the image is blurry or at least some detail is lost.
Wherever possible I've been trying to avoid any noticeable noise, but looking at my past vacation photos I think letting there be noise was the reason why I got a decent shot in the first place.
As I've heard from other photographers, you can use technology to remove noise and you can spend all day tweaking exposure, but removing motion blur is a much tricker thing to do later on.
So I decided to take my one user setting that I typically use to take photos of my kids or other moving subjects and I cranked the maximum AUTO-ISO to 25000 and turned off the in-camera noise reduction, then took a few random shots around the house.
This photo is also zoomed in and cropped from a portrait orientation.
In this low-light shot of my cat you can see a lot of noise, but also things like her whiskers or the fur on her ears aren't blurry from movement. I might continue to tweak these settings, but I'm leaning towards keeping this look. Over the next couple of weeks I'll focus more on low-light shooting to see how well this pans out. I’ll bet some photos in otherwise decent light don’t change, but I'll also keep an eye on that too. For now I’m willing to embrace the noise.