Hi John - First of all I processed flat data at a later date to the light data (using lum filter) and I didnt change the focus in anyway when I moved the scope indoors.
I then decided to use the nebulosity pre-processing guide from here - https://www.google.c...vtW3jmeaa1FLlD2
The steps I took in nebulosity were as follows:
1. I took 25 flats using lum filter and stacked them togather i.e. align and combine.
2. I took 14 darks using the same time and temperature to what the light data was taken at and then stacked them togather i.e. align and combine
3. I then selected batch and pre-process option where I selected my master dark, master flat and applied them to each image file. i.e. I had 8 lum frames to which I applied master dark and master flats.
4. I then normalised intensities for each of these 8 processed files (normalise light levels)
5. I then batch demosic and square raw color to all 8 processed files (No idea why! I'm just following instructions)
6. I then took the 8 proccessed files and aligned them using align and combine translation method (but save each file not stack).
7. I then for the final time (again) align and combine but this time use the stacking function std. dev filter (1.5 - typical). (Again no idea why)
8. I look the at the final image and cry.....
Did you also take any Flat-Dark frames? You need to use some Dark Frames of the same exposure length as the Flat frames. You would then subtract the Flat-Dark frames from the Flat frame before using it to calibrate your target light frames.
No idea I had to do this.
I'm going to do some more reading and testing and update this thread once completed. (Its been a tough weekend)
Edited by Manav, 08 September 2019 - 06:21 AM.