Quick Nikon question

[reid506]

I have a Nikon D90 and I have a question about High ISO Noise Reduction. Within the High ISO NR feature there is high, normal and low. I've read the manual but to me it's not clear. Does High mean that the camera will reduce the most noise that it can or is it that Low means it will have the lowest amount of noise? I want to shoot at a very high ISO tomorrow inside a gym (gymnastics) and I want to reduce as much noise as possible with the camera. I hope this makes sense.

Thanks,
Reid

[kirbinster]

High takes a picture without the shutter open and maps the noise from the sensor and then subtracts that from the picture you are taken. It does slow the camera down a little, but will help get a better quality image.

[inkista]

Kirbinster, are you sure about this?

On the Canon side, we have two different settings, one for overall noise reduction (which is what the low/medium/high settings sounds like), and a separate "long-exposure NR" setting, which is the dark-frame subtraction (which always doubles the amount of time to take the shot, because the dark frame has to be taken with identical settings) you describe. The former is basically just choosing how much NR processing to apply.

As with JPEG compression, where it's a quality/size tradeoff, with NR, it's usually a detail/noise tradeoff. The higher your NR processing, the less detail you're going to see (i.e., more pixels get smeared together to reduce more noise). The less NR processing you have, the higher the amount of detail, but the more noise (fewer pixels get smeared together).

This is why sharpening and NR tend to be antithetical to each other when you post-process.

[reid506]

Okay, so would it be better to keep it at low or normal ISO NR and see what I can do in Lightroom later? I know LR will basically do the same thing as far as smearing pixels but it seems the sliders may give more control than the three settings in the camera.

[kirbinster]

No, actually what I was talking about is the long exposure NR - sorry.

[inkista]

Originally Posted by reid506

Okay, so would it be better to keep it at low or normal ISO NR and see what I can do in Lightroom later? I know LR will basically do the same thing as far as smearing pixels but it seems the sliders may give more control than the three settings in the camera.

To me, yes. You can always smear the pixels more, but smearing less is a lot harder. It's also why I shoot RAW and at highest resolution even if I'm planning on making a JPEG B&W web image: you can always discard data, you can almost never get it back if you discarded it in-camera.

Originally Posted by kirbinster

No, actually what I was talking about is the long exposure NR - sorry.

Hey, no worries. I screwed up what the AF settings were called on a 50D (and I shoot with one!), so I know what it's like.