Hi, For best image quality with automatic long time exposures with the *istD is it best to use the lowest sensitivity? Should I take a 30 sec exposure on 200ASA; a 15 sec on 400ASA; or an 8 sec on 800ASA? I haven't done any real tests but I have tried some shots using 200-800ASA and they all came out with very little noise. Shots using 1600ASA start to get noisy and shots using 3200ASA are like video camera freeze frames. What's the theory on this? (As an aside, I notice that the *istD noise reduction function takes a very long time to do its job - the first time I took a long exposure it took so long to preview the picture that I thought the camera had failed!). Incidentally I found that I had to overexpose by 3 stops to get reasonable images.
Nenad
