M101. More progress

[jacko61]

M101 from last night. (compressed in windows 7 as the saved JPG is 19Mb!) .Around 2 hours capture altogether (including darks).  30 x 240 seconds at iso800. I found a handful of duff frames because PHD2 went haywire a couple of times and at least 7 frames with satellite trails.  Someone on facebook advised me to switch kappa-sigma on in DSS which cleaned the satellite trails. Processed today in GIMP. My next project will be figuring how to automate a meridian flip so I can start doing extremely long sessions without having to visit the shed every half hour. I also need to understand Bias and Flat frames.

graeme

 

    

Edited April 16, 2021 by jacko61

[wimvb]

Very nice. The galaxy has a green cast which shouldn’t be too hard to remove.

12 minutes ago, jacko61 said:

My next project will be figuring how to automate a meridian flip

What capture software do you use?

[jacko61]

2 minutes ago, wimvb said:

Very nice. The galaxy has a green cast which shouldn’t be too hard to remove.

What capture software do you use?

APT.   PHD2 for guiding and DSS for stacking. Odd cast though - it didn't look like that earlier. Maybe the compression has done something. I'll post the full size file in a minute

 

[jacko61]

I've reduced the green level in curves. Looks much better..

[Mark Hardaker]

Isn't this M101, not M51 though?  Great image though.

 

[jacko61]

4 hours ago, Mark Hardaker said:

Isn't this M101, not M51 though?  Great image though.

 

[removed word]. mind was elsewhere. Well spotted. title changed

 

[jacko61]

Had another play in GIMP after I added 50 bias frames to the stack. I doubt I'll get it looking any better without a lot more data.

Graeme

(didn't realise the forum removed rude words - I'll bear that in mind in future) 

[wimvb]

7 minutes ago, jacko61 said:

didn't realise the forum removed rude words - I'll bear that in mind in future

It’s family friendly. Unfortunately , it does the same in private communications, resulting in ordinary Swedish words being removed from messages. 
btw, your image looks a lot better now.

[Mark Hardaker]

The forum seems to have no problem with the word GIMP though, which has other meanings then the one we know!  Big improvement in the image, by the way.  Did you get some flats and biases in there yet?  Some of our local astro soc members helped me understand and shoot some flats and the difference was immediate and enormous.  I also tried some bias frames (easy to shoot) but the difference wasn't as great as adding some flats into my DSS stacks.  Good luck!

[jacko61]

Thanks Mike.  I did add 50 bias frames but I'm still reading up on Flats so hopefully I'll be able to improve the image further although I think a course in using GIMP would be a great idea

Graeme