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Old 20-10-2015, 09:44 AM
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Rod771 (Rod)
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Rod771 is offline
 
Join Date: Aug 2012
Location: Parklea NSW
Posts: 1,207
Quote:
Originally Posted by Shiraz View Post
yes, it was one of the light subs. The DBE background was then applied just like a normal master flat would be - (you must set downsample under model-image to 1 though). It gets rid of vignetting and even helps with the worst effects of large donuts (if you use enough sampling points). It does not do fixed pattern noise reduction, but dither can take care of most of that - it's not as good as a real flat, but still useful if you have problems getting flat data. You don't get a lot of signal in the synthetic flat, but, being a fitted surface, it is essentially noise free. if you do try it, be interesting to hear if it works well enough - I guess there will be issues with a DSLR due to the Bayer filter, but you should be able to find a way round them.
Must be my Hyperstar flats curse. Or I just keep ballsing it up, Ray. I applied the synthetic flat (downsampled to 1) but it over corrected the vignetting by quite a lot. I tried both the image cal tool and BPP but got the same result.

At work atm, I can attach a reference later today.
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