Quote:
Originally Posted by Amaranthus
DSS uses dcraw as its RAW decoder (get the latest 'beta'), so I'm not sure of the advantage of doing the conversion outside of the stacking program.
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Yes it does Barry but it modifies the data. By using dcraw first with the arguments Ivo suggests it gives cleaner data.
This is how Ivo described it to me (I hope he doesn't mind me reproducing this here):
The main thing is that DSS no longer should meddle with the colour balance and should no longer create anomalous colour data in the highlights.
The problem with modifying the colour balance before StarTools can analyse the data is that any noise levels will be skewed due to the multiplication (which is what whitebalancing does) of the signal (and thus noise) in the individual channels. Highlights get clipped by the whitebalancing as well, introducing anomalous colour data in the highlights. This is why you'd want to give StarTools data that is as virgin as possible. The Tracking feature will be able to work better and will help the various modules yield better results if it can oversee the full noise evolution.
I have compared final images with using RAW or TIFF (converted first by dcraw) into DSS and the TIFF stack gave a less noisy final image with more dynamic range.
Here is an example:
http://www.astrobin.com/93400/C/
A & B were done with RAW, C was done with TIFF.