Here is a processed image made with my electronically assisting astronomy (EAA) rig.
Celestron-11, f/6.3, ZWO ASI290MC video camera, live stack of 49 6-second exposures
Perhaps the image would have benefitted from using my atmospheric dispersion corrector (ADC), since the nebula was quite low in the sky. Maybe this is why there are blue fringes on one side of the bright star images. Also I need to explore including a dark frame* with the stack process, since there were many hot pixels. Most of these were removed from the image above. Likely all the green stars are groups of hot pixels.
*Dark frame subtraction is available in the Pro version of SharpCap. I've gotten a one year's license for SharpCap Pro. This will add many useful features.
- Date and time of the observation = 2020 February 17, ~20:00 local time
- Seeing & transparency conditions = fair seeing and transparency
- Name of subject = NGC 2438, 1.2 X 1.1 arc-minutes (planetary nebula in foreground of M46)
- Software/process used for the “live” capture = SharpCap, 294 seconds via 49 frames
- Discussion of observations:
After a go-to M46 (which was too large for the available FOV), I scanned around (with 1-second, high gain integrations) until the planetary nebula came into view as a ghostly disc. Then gain was adjusted to a mid value for the live stack shown. I was mostly focused on getting the hardware and software issues resolved. But the annular form and reddish rim of the annulus were noted as the stack was built. Most all of the bright stars are members of the open cluster M46.
I hope you enjoy.
Edited by Rustler46, 20 February 2020 - 03:37 AM.