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Old 22-01-2009, 07:42 AM
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bojan is online now
Join Date: Jul 2006
Location: Mt Waverley, VIC
Posts: 6,054
Originally Posted by Octane View Post
I don't know what algorithm is being used to subtract data.
That is a good point.. however, how do you know other tools are using algorithms that do not destroy original data? It would be nice if, for example, if DSS could be configured with more options...

I was experimenting a lot with my 400D and it seems it uses simple numeric subtraction. Of course, after de-Bayering, which is a huge compromise and an issue with all DSLR's (except some from Sigma, they use Foveon chip).
Some other cameras are known to use funny algorithms to remove noise, though (Nikon, for example, as demonstrated on Christian Buill's website).

(sigh) if we really want to have absolutely raw data, DSLR's should not be used.. only the camera with B/W CCD and standard filters collects data that are not distorted by un-documented algorithms, so they have scientific value.
But, as Frank, said, it is about fun.. we are all amateurs (like it or not), not professional scientits.

Last edited by bojan; 22-01-2009 at 08:16 AM.
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