1.- FITS CALIBRATION (and Dark sites night skies)
After many years fighting againts terrific "gradients" we have learned about the key importance of right dark night skies as an fundamental part of astrophoto general quality. Specially when you are planning to go deep inside dusty clouds and dark nebulas in almost RGB regions with no large Ha emission nebulas nearby.
So you can say that you have done a great part of the work, when you shot from a quite dark and high observation site.
Fits quality enhancement is a critical step to go deeper with very dim objects you want to cath. You should only use the best frames you get. After that, calibration routines become a less dificult part of the bussines.
We use regulary Maxim DL to calibrate our fit frames with BIAS, DARKS and FLATS (between 25 to 35 per each).
2.- FITS COMBINATION
When the calibraton work is done, we combine also with Maxim DL all fits per channel (R, G, B, L IR-UV, Ha,...) using sigma clip for outliers rejection.
3.- HISTOGRAM EXPANSION (or how to take starsizes under control)
After combination, we usually have an L, R, G and B set of master frames to process further. For histogram expansion we use PIXINSIGHT software, giving a great control with starsizes and the most iluminated areas in the pic.
4.- RGB CHANNEL COMBINATION FIRTS FOR COLOR BALANCE ACHIEVEMENT
5.- INTRODUCING LUMINANCE -IR UV FOR DETAIL ENHANCEMENT
