Monday, May 4, 2015

Problems with dusk flats with CCDAP

I am still using CCD AutoPilot for taking dusk (or dawn) flats. It works pretty well, but often it takes a few images until the algorithm works well. What I observe a lot (~ 50% of all evenings):
  1. CCDAP takes an flat (ADU is within the range of the target ADU)
  2. But then CCDAP decides to take a shorter exposure for the next flat
  3. After taking that flat, CCDAP needs to correct the exposure upwards and then the flat has the correct ADU level
This happens at the beginning of a sequence and is usually over after 1-4 flats.

Asked on the CCDWare forum about this.


Update May 6: John Smith contacted me and send me a beta that might fix the first issue. The problem that he saw was that my flats try to get an average level of 47,000 ADU - which is higher then what CCDAP was originally designed for. The beta had a higher threshold. I tried it out one evening and it worked perfectly!!!