Ic 342

[Nicola (Nicola)]

I had already shot this galaxy before:

http://skymonsters.net/immagine.php?img=IC342.jpg

with some satisfaction, but I thought I could squeeze some details by integrating more, so I started to image it again. Unfortunately the camera angle was way different from the first try therefore I could not add the new frames to the old ones. Nevertheless, I am more satisfied by the latest rendition.

http://skymonsters.net/immagine.php?img=IC342_2.jpg

C&C always welcome

[alpal]

Hi Nicola,
excellent job.
Why wouldn't the 2 sets of data stack?
Of course you would have had double diffraction spikes but they could have been processed out.

cheers
Allan

[Atmos (Colin)]

The new version looks a lot better than the original, the galaxy pops out a lot more. Well done

[willik (Willik)]

Slightly out of focus but still a very nice image
Martin

[Nicola (Nicola)]

Originally Posted by alpal

Hi Nicola,
excellent job.
Why wouldn't the 2 sets of data stack?
Of course you would have had double diffraction spikes but they could have been processed out.

cheers
Allan

Hi Allan, thank you. The angle was so much different that the intersection of the two frame sets would chop a big portion of the frame, something I didn't want to.

[Nicola (Nicola)]

Originally Posted by willik

Slightly out of focus but still a very nice image
Martin

Hi Martin, can you please elaborate on this? I was focusing with focusmax and I had an FWHM of 2.5 arcsec. On the best nights I can go down to 2.0 but it is rare.

[willik (Willik)]

Your stars are ok the galaxy looks slightly out if you used photo shop for process try and sharpen the galaxy only unsharp mask this might help
unless the night was not very good for imaging.

[Nicola (Nicola)]

Originally Posted by willik

Your stars are ok the galaxy looks slightly out if you used photo shop for process try and sharpen the galaxy only unsharp mask this might help
unless the night was not very good for imaging.

Thanks for pointing it out, I'll try it and let you know the results.

[astronobob (Bob)]

Very nice Improvement image of a very nice galaxy there

[gregbradley]

A very good rendition of this galaxy. Its an odd galaxy that must be obscured by some dust which gives it the reddish look.

Greg.

[Geoff45 (Geoff)]

Very nice Nicola. I was also wondering about the reddish colour. Presumably obscuring dust

Originally Posted by alpal

Hi Nicola,
excellent job.
Why wouldn't the 2 sets of data stack?
Of course you would have had double diffraction spikes but they could have been processed out.

cheers
Allan

Off topic. No, you won't get double diffraction spikes. The orientation of the spikes in the image depends only on the orientation of your spider not the camera. Just think about the image in the image plane without the camera and suppose star A has a diffraction spike pointing directly to star B. Now bringing in the camera (in whatever orientation) is not going to change this.

[alpal]

Originally Posted by Geoff45

Very nice Nicola. I was also wondering about the reddish colour. Presumably obscuring dust


Off topic. No, you won't get double diffraction spikes. The orientation of the spikes in the image depends only on the orientation of your spider not the camera. Just think about the image in the image plane without the camera and suppose star A has a diffraction spike pointing directly to star B. Now bringing in the camera (in whatever orientation) is not going to change this.

Hi Geoff,
That seems correct.
I wrote it because when I was a beginner in 2011 I took
an image here:
https://www.flickr.com/photos/24719437@N03/5891049441/
& ended up with multiple diffraction spikes after stacking the data -
the bright star in the top left hand corner.
I wonder why?
Was it the before & after meridian flip that caused it
or a bad polar alignment?

cheers
Allan

[Geoff45 (Geoff)]

Puzzling Alan. Looking at the individual subs may give a clue to what's going on. Possibly something projecting into the imaging path.