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 p.1 #4 · Best 4/3 camera for extended shutter speeds | |
scribble wrote:
Alright, I was aware of the cooled CCD option, however, there is no option for that in the 4/3 system. I was wondering if the E1 would work, due to the CCD sensor, instead of the LMOS sensor of the newer bodies. Kodak designed sensors seem to work with heat fairly well, or at least that was my impression with the SLR/c I had for a while.
The E-1 is pretty long in tooth, and even with its relatively larger photosites it has a hard time keeping up with newer cameras. An E-400 is a possibility if there's something about Kodak's CCD that you like over Panasonic's NMOS, but I think most people would be hard pressed to find differences relative to your E-420. Both have relatively heat generating sensors buried inside a relatively insulating camera body. Also you'd have to give up live view for an E-400.
scribble wrote:
Now, I am not fully aware of the process of stacking exposures, if you could explain that one a bit further, I would appreciate it.
Steven
Stacking for noise reduction (versus stacking for DOF, stacking for resolution, or (explicitly) stacking for dynamic range) requires that there be a gap between the noise floor and the beginning of the meaningful signal (ideally the blackest black) in each frame of the sequence. It also requires that the frames align precisely. As long as these conditions are met, each additional frame allows the wanted data to grow stronger, while the mostly random noise stays about the same. As this gap grows, the desired image pulls away from the undesired noise, and the later can be safely discarded by levels manipulation. It's how I was able to lift stars which would be invisible in a single image off of a salmon coloured sky glow (a bigger problem than sensor noise in that kind of shooting).
It also allows a shooter to make images whose effective exposure would be impractical (hours or days) or impossible by single shots.
Many software packages are available to automate the process, though most are targeted at astrophotography. I used Iris for the above stack, but a search for "image stacking noise" will turn up more options.
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