|
Jon. The reason for not addressing calibration of Pat's frames in this instance, is that the striations in the image can occur with or without calibration. Hopefully, there will be improvement with calibration.
I will go so far as to say that DSLR frames should be dithered aggressively. But dithering is not a replacement for calibration - bias darks and flats. Dithering will sample as many different pixels as frames and separate any sensor artifacts by a respectable distance, so they never meet up when stacking.
In general - Increased sub-pixel sampling - pixels vary in performance. Flat field improvement. Masking of sensor artifacts - hot and cold pixels and cosmic ray artifacts. Noise reduction. And, a biggie for Canon users, banding is eliminated, as far as I can tell, completely, in the stacked image. Overall improved SNR and less post processing overheads
In short, if you can find a way to dither with your gear, do it. It's for beginners as well as the pros.
BTW. I have corrected the sequence in the previous image. Been a long time since I've had to think about it, as dithering has been sequenced with image capture, automatically for some time now.
|