Contains:  Solar system body or event
Rosette Nebula, 


            Casey Offord
Rosette Nebula, 


            Casey Offord

Acquisition details

Dec. 4, 2020
25×600(4h 10′)
4h 10′
Avg. Moon age:
18.61 days
Avg. Moon phase:

Resolution: 2928x2940

File size: 4.3 MB

Data source: Backyard


This was my first real session with the Optolong L-Extreme filter. With the 84% moon, I think it was a good test. Other than some guiding trouble (seemed to average out around 1.8" RMS error), it was a great night of imaging. I think the error was due to the gears being a bit too tight after adjusting to remove backlash.

This was also my first try at a quasi-HOO integration. I extracted RGB channels from the integrated image, made Ha and Oiii channels using PixelMath, and then combined them with Ha for red and Oiii for green and blue. I'm not sure if I did HOO correctly but it seemed to improve the overall image so I went with it.

Any comments are welcome!



Rosette Nebula, 


            Casey Offord