Looking for guidance
I have followed the tutorial regarding pre-processing. Used my super bias and master dark to calibrate my flats (taken by imaging a laptop screen with Notepad filling the screen) Up until a few weeks ago I didn't bother with flats as the DSLR camera was clean, now I have a large dust mote somewhere in the imaging train and I need to remove it with flats.
I have the following problem. When using the super bias, master dark and the master flat produced I get a very red image. The image is still bright red after using the Screen Transfer Function, with a hint of stars showing through. Using the Background extractor shows the image, but it still has lots of reddish gradients which I can't get out using post-processing techniques.
If I calibrate the Lights only using the super bias and master dark and no master flat, I get what looks like normal images. The bright red has all gone. However, with no flats applied the dust mote is in evidence and spoils the image. The Master Flat produced after calibrating with the bias and darks does show up the dust mote, but somewhere it is destroying the calibration of the Lights.
The images are still bright red if I only use the super bias and the master flat. Calibrated the Flats just using the super bias but still end up with the bright red image!
Any assistance, guidance would be very welcome. Please don't be too technical and PI is relatively new to me.
Alec
