Quote:
Originally Posted by Craig_
I think different people and different software approaches it differently. But, the idea is that you may need to calibrate your calibration frames.
Eg, darks may be calibrated with bias. Flats may be calibrated with bias or dark flats. Dark flats may be calibrated with bias. Bias is not calibrated by anything. Lights are then calibrated by the masters of all of the above.
Although I don't use PixInsight much the workflow I follow with that is basically - create master bias, create master darks by calibrating from master bias, create master dark flat by calibrating with bias, create master flat by calibrating with master dark flat, then use bias, flat and dark masters (but not dark flat master) to calibrate lights. At least, if memory serves, this was my process.
In APP I just stick all calibration frames into it and it does the work, but if for example I try and make a master flat without adding bias or dark flats it will have a whinge that it needs to calibrate the flats (with bias or dark flat) to make an accurate master flat.
Aside from processing software, individual cameras will also vary in terms of requirements, eg I have heard bias frames do not work with certain cameras, and for example on the 533, I can generally not bother with darks as long as my data is well dithered, as the combo of dithering and pixel rejection algorithms in the integration means that all hot pixels are removed and thermal noise is very low anyway. I have never been able to perceive much, if any, difference with the 533 between a stack from well dithered data sans darks, and the same data with darks.
|
Thanks Craig
I think next clear night ( hopefully on the weekend with a big ol moon up ) I’ll capture some lights say an hour on a target like M17 , capture my Flats and dark Flats , take some darks and Bias too
Then experiment on calibration with DSS and compare results with various methods
Vignetting and dust donuts are my main issue
I’ve thoroughly cleaned my camera sensor, protective window , coma corrector and L Extreme filter under a led mag lamp ( doesn’t guarantee your free of dust donuts )
Cheers
Martin