james_kimber Posted February 3, 2008 Share Posted February 3, 2008 I am using a Nikon D200 and the fastest glass I have to pair it up with is a Sigma 28-105mm f/2.8-f/4. Typically, I never have to shoot in any situation that would require me to go higher than ISO 400. However, the other I ran into needing to push the D200 to 1600 and higher (something I've never done before). Although I know the camera is completely capable of getting fairly clean shots at these ISOs, I wasn't so hot at it. I was exposing everything as I normally would at any other ISO and saving in RAW. Also, I was using a monopod vice a tripod, and there was very little to no action. Was the monopod with slow action my main problem for getting "noisy" images? Or are there other secrets that you low-light photographers have that I don't know? Any help would be greatly appreciated! Link to comment Share on other sites More sharing options...
sattler123 Posted February 3, 2008 Share Posted February 3, 2008 You need to watch your exposure very carefully when you shoot high ISOs. Nothing creates more noise than an under-exposed image. You need to look at your historgram after you took a shot and then adjust the exposure, so that the histogram is pushed to the right as much as possible without clipping the highlights. As soon as you need to push the exposure in post processing aka in your RAW converter you introduce tons of noise. Try it - it really makes a huge difference. Link to comment Share on other sites More sharing options...
james_kimber Posted February 3, 2008 Author Share Posted February 3, 2008 So I would usually need to slightly overexpose? Is that so the blacks are closer to true? Link to comment Share on other sites More sharing options...
jobo1 Posted February 4, 2008 Share Posted February 4, 2008 The main source of noise (poisson noise) depends only on how much light hits the sensor, i.e., shutter time and aperture. A picture taken at ISO 1600 and one taken at ISO 800, with the same shutter time and aperture and brightened by one stop in post, have the same amount of poisson noise. Then there is readout and reset noise, which is "constant", and shows up more when you underexpose and later brighten the picture. As you say, it has an impact mainly in the darker areas of the picture. Link to comment Share on other sites More sharing options...
james_kimber Posted February 5, 2008 Author Share Posted February 5, 2008 Great! I will give your advice a whirl this weekend. Hopefully, the results will be better. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now