NGC 281/Pac-Man Nebula in Ha/Oiii

[jnelson]

After a month of limited imaging, a break in the weather. Grabbed enough frames of NGC 281 to post a presentable image. Stars are a tish bloated due to a degree of over sampling but was able to stack 90 x 120s for total integration of 3hrs. Captured with C8 & ASI533MC using Ha/OIII filter. Soon to move up in the world with the purchase of a C11 matched with a CGX mount. Looking forward to giving that a whirl. Thanks for looking!

[AstroBee]

It looks like you are off to a good start but you definitely have some issues to work out.
Either your collimation, guiding, or focus or all three were off. One thing you can try to do to fix the over-sampling is to bin your images 2x2. I'm not sure what software you used to capture with but there's a binning setting that will allow you to make that adjustment. That will get you down into the good range. Heck, you could even bin 3x3 with your setup and still be in the right range.
Keep at it! Looking forward to following your progress. I would recommend getting better with the equipment you have rather than spending more money on new gear. With a larger scope like the C11, your skills are going to need to be even more on point to get acceptable images.

[jnelson]

Yeah definitely not one of my better efforts compared to previous postings. Recently checked my cultivation and appeared good but can always re-check. Tracking was good since I’ve been using an an OAG with the SCT but I do think my focus may have been a bit off. Guess it’s back to using the Bahtinov mask. I tried a star reduction technique with GIMP but I think that actually made in the Remaining stars even more bloated. May finally give Pixinsight a try. DSO imaging is definitely more challenging with an SCT than with a refractor. Still going to be using my current rig and keeping the big rig in a permanent dark sky location. Thanks for the advice.

[jnelson]

Appreciate the thanks! Re-checked star collimation and it was almost spot on. Don’t think focus was the issue. Went ahead last pm and re-imaged the target but stacked 0.63 & 0.5 reducers to shorten the FL (f/3.3) which hopefully will reduce over sampling by bringing up the the image scale from 0.63a-s to 1.14a-s, although did notice minor vignetting at the edges during livestack. Thinking about purchasing the Starizona night owl 0.4 reducer when available. Grabbed 33 x 120s subs but haven’t processed yet but stars looked better in livestack. Still going to use GIMP since I’m most familiar with it but may skip the star reduction. Will post when done.

Got the C11 & CGX and will be toting to our dark sky lake home but plan to initially use it for planetary & lunar imaging.