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Hi Mabula
Using APP 1.061 and getting great results. I have a query about creating BPMs
Can a BPM created with darks of one exposure time be used on lights of a different exposure time? Or should I create separate BPMs using darks of say 300s and 600s to match the corresponding lights. I notice that the header data, using hot pixel kappa=3.0 and cold pixel %=25, give %HPs of 0.3 and 0.9 respectively for 300s and 600s darks. Is this a reasonable level for my ZWO ASI071C? Certainly the visual number of hot pixels seems quite a bit less than in the BPMs.
Also do I need to match the sensor temperature when creating BPMs to the lights I will use them on
Many thanks
Chris Marshall
A Bad Pixel Map can be used for all your data and for a very long time as well. No need to match anything.
Hi Chris @chrismarshall800gmail-com,
Indeed, like Vincent @vincent-mod indicates, simply create 1 effective Bad Pixel Map using a nice set of darks and flats and you will be able to use it on all your data shot with the sepecific camera.
You can see the Bad Pixel Map as a map of how the sensor in your camera works. It's not dependent on a ISO/gain value and not on exposure time.
To create the Bad Pixel Map, you will get better results if you use:
- more darks
- longer exposure times
- higher temperatures
The goal is to get good statistics on the linearity of the pixels on your camera's sensor. With more darks, longer exposures, and higher temperatures, you get better statistiscs 😉
Kind regards,
Mabula
