iso or aperature?

[bballboy30]

I was wondering that if you had enough light what would you do first - lower iso or close down aperature? I mainly shot wildlife so this situation doesn't usually happen. But in case I got enough shutter and could afford to lower iso or close down aperture what should I do first?

Thanks.
Alex

[KevC]

If you need less shutter, I'd lower ISO. First. Why? Lower ISO produces less noise.

If you need more shutter, I'd widen aperature first. Why? Lower ISO produces less noise. :)

However, if you need a certain DOF, then you'd be forced to raise (or lower) ISO. So really, it all depends on the situation.

[Curtis N]

Lower ISO, in a heartbeat. Unless I really need the DOF with a smaller aperture.

A picture with a shallow DOF is only partly blurry. I picture shot at 800 or 1600 ISO will have noise all over it, including what you focus on (such as someone's face).

The caveat is that digital noise is more noticable with larger prints. On a 4x6 you'd struggle to see a difference between 100 and 400 ISO.

[tim]

I don't mean to be rude, but i'd suggest doing a basic photography course, so you understand what's going on rather than doing what people recommend. They're basic concepts but I found them much better taught in person than by reading on the net.

[Citizensmith]

I agree with Tim. There are very important reasons why to change appeture, shutter speed, or ISO that go much beyond 'is there enough light'. You may want to try a few basic things with your camera that will help you see this. Taking the same photo at varying ISO and appeture and reviewing the results you be a good start.

Additionally a lot of people work very differently to your suggested method. I have the camera set on ISO200 and f/8 (for my f/4 lenses) or f/5.6 (for my f/2.8 or better lenses). I only start paying attention to shutter speed of it gets too low to handhold. If I need more light I'd push the ISO to 800, then open up the appeture, then push the ISO to 3200. I prefer to change appeture because I want to not because I'm just countering for changing light levels.

[lancea]

I was wondering that if you had enough light what would you do first - lower iso or close down aperature?
Hi Alex. I think you've asked a valid question in the context of digital cameras.

Something to keep in mind is that the newer cameras have significantly less noise at higher ISO settings. I tend to use 200 ISO on my 20D, but have gone all the way to 3200 for "desperate" shots where a flash could not be used. The noise levels are much lower in the 20D than with my Olympus pocket camera at its highest settings.

If you were operating at one of the high ISO settings (e.g. above 400) then it would be appropriate (depending on the noise levels of your camera) to lower ISO first. If you're already using 400 ISO or less, then lowering the ISO might not give a useful reduction in noise. If you don't already know where noise becomes noticable on your shots, then do some tests.