RCC: M31 - Forums

Hi,

I’ve just started using PixInsight and am relatively new to astrophotography in general. I processed data on M31 (https://astrob.in/yn3mn2/0/) and am looking for overall suggestions on next steps and areas to improve. I’m colourblind so I’m hoping to get some feedback on the colours in the image and the saturation levels especially.

Thanks!

Ewen

Looks pretty good! Everybody's tastes are different, I personally would go a little less blue in M31 but it's a nice contrast with the core.

Unrelated to color, you appear to gave a backspacing issue. All corners radiate outwards indicating the sensor is too close to the flattener. Try adding some spacers. Remember to add 2/3 the thickness of any filter being used to your backspacing.

https://optcorp.com/blogs/deep-sky-imaging/how-to-set-the-correct-back-focus

Thanks for the comment on M31. I did notice that I have a backspacing issue. I’m pretty new and thought I needed 55mm. In fact my set-up needs about 70mm. I have better spacing now. I’m waiting on a clear night to see if the issue has been corrected.

All the best,

Ewen

Do you have a field flattener? If so, then backspacing is your only significant issue impacting your image.

I think over all the colors are great, except the transition from the core to the outer regions, from the gold to cyan is a little abrupt. I don't know much about pix insight, but that type of issue in astro pixel processor usually comes up with color calibration and adjusting the slope to make a more natural transition usually takes care of it. I tend to also like to crush my stars a little more but you have good color in them

Very nice image Ewen! As mentioned above defiantly have a backspacing issue but other then that the color & contrast are mainly a personal taste thing at this point. For me I think I would experiment in PI using a mask and try a slight HDR transformation just to see if I could pull a tad more detail out of the core. But again thats just me and my tastes.

Great image over all except the back spacing issue.

Dale

Thanks Dale,

I agree that the backspacing is an issue. I think I now have it solved. I’ll look into the hows and whats of HDR transformation and see if I can create a revision.

I do appreciate the feedback.

Ewen

Do you have a field flattener? If so, then backspacing is your only significant issue impacting your image.

Hey,

Yes I do have a field flattener and I think that is why I have the backspacing issue. I didn’t initially think about how it would change my backspacing away from 55mm. I connected with WO and my Flat 73 requires about 70-71mm backspacing. I’ll be playing around with that number and hope that my future images won’t have the same issue.

Thanks for taking the time to comment. Clear skies.

Ewen

Do you have a field flattener? If so, then backspacing is your only significant issue impacting your image.

Hey,

Yes I do have a field flattener and I think that is why I have the backspacing issue. I didn’t initially think about how it would change my backspacing away from 55mm. I connected with WO and my Flat 73 requires about 70-71mm backspacing. I’ll be playing around with that number and hope that my future images won’t have the same issue.

Thanks for taking the time to comment. Clear skies.

Ewen

Always handy to have a ruler around to measure precisely. Good luck and of course, clear skies.

Blaine Gibby:
I tend to also like to crush my stars a little more but you have good color in them

Thanks for the critique! I think I might need to increase the “fuzziness” on my range mask in PixInsight to allow for a smoother transition. I’ll give that a try in my next revision.

Also, I want to make sure I understand what you mean by “crush” your stars. Do you mean that you like to reduce them?

Thanks!

Ewen

Yes, I like to reduce them. Typically I separate them from the DSO and then process them separately

I think this is a pleasing image, I particularly like the nebulosity.

As you are using Pixinsight, you may like to try the free trial of BlurExterminator. to see how it performs fixing the elongated stars in the corners.

I have no affiliation with RC-astro, just a happy user.

https://www.rc-astro.com/resources/BlurXTerminator/index.php

Looks good so far and some good feedback. One thing you might try that I've found particularly helpful on M31 is the Dark Structure Enhance script. At least i think that's the name. It's in the script menu, not the processes. Will help bring out those dust lanes a little more.