Godfrey, Thanks for the tip on the Lightning. Wow. I didn't know about that noise reduction technique in the camera. Your comparison images are quite enlightening.
So if you leave it off most of the time, do you turn it back on when your shutterspeeds are slower than 1/25s? dk On 7/14/05, Godfrey DiGiorgi <[EMAIL PROTECTED]> wrote: > >> This is called "dark frame subtraction" a form of noise reduction. > The DS has NR of this sort turned on by default, it goes into > operation at about 1/25 second. You can turn it off using a custom > function (I think it's on the first page of the Custom Settings menu). > > > The only theory I could come up with, is that the body reads > > continually from the sensor during the exposure, and then when the > > shutter closes, the body compiles the image from memory. (I was > > shooting in Jpeg). Would Raw have been quicker? > > This has nothing to do with it. > > To give you an idea of how effective the DS' noise reduction can be, > here are test shots from the DS, one made with NR off and another > with NR on, both processed with identical settings in Vuescan and > Photoshop+ACR 3.1, respectively: > > http://homepage.mac.com/godders/straight-NR-comp.jpg > > I chose to use two different RAW conversion programs for this example > as Vuescan does not do hot pixel removal where ACR does. Normally I > process with ACR. > > Some folks have found that having NR on can influence sharpness at > short shutter times, so I normally have it switched off. > > Godfrey > >
