Hi All,
I’m getting an odd blue patch in the middle of my frame and I can’t for the life of me figure this out. Here’s a screenshot of the result from WBPP. I’ve also included in the screenshot the low and high rejection images. Im using flats and flat darks that I believe have all been done properly with matching temperatures, exposure times, etc. The light patch does show up in the flats but it’s just not calibrating out. I’ve reshot the lights, dark flats and even tried calibrating with bias frames but I can’t find a solution to this.
I’ve also added a screenshot showing the image after a bit of rough processing (over saturation to show the effect). I tried using various gradient removal tools but just can’t get rid of it. This is over 50 hours of data so I really don’t want to loose it.
ASI533MC Pro, ZWO FF65, Astronomik L3 filter.
Here’s a link to the master files and logs:
https://drive.google.com/drive/folders/1pf0Q3ghhq-fFQFM4pic8gNUv4-zMeleM?usp=sharing
Any help would be very much appreciated.
📷 Screenshot-2026-07-15-at-19.12.22.png
📷 Screenshot-2026-07-15-at-19.13.08.png