Jellyfish and Monkey Head

[Zummerzet_Leveller]

Just 2hrs 45mins of 5min exposures.  2600MC, Lextreme, Redcat51 on the AVX.  Siril (with Starnet), Topaz and Gimp for processing.  Excuse the elongated stars, I've been trying to fix the stars in the corners when I have a filter in and seemed to have gone the wrong way with backfocus.

[Astroscot2]

Lovely image, I'm working on the same area myself. Same kit but slightly different framing to include M35.

[simmo39]

Wow, that is a great work. You seem to be banging them out at the moment. I gave up on the M81 M82 image, just couldnt get it right and to top it off I now have an LED street light ove my garden! but as they say no pain no gain.

[Zummerzet_Leveller]

1 hour ago, Astroscot2 said:

Lovely image, I'm working on the same area myself. Same kit but slightly different framing to include M35.

Thank you for the comment, slightly bigger FOV with the 2400 which would work nicely to get M35 in, I think I would have struggled with the 2600.  How do you find the stars in the corners of your images with the SpaceCat and the full frame sensor on the 2400?  I've been struggling with a bit of coma at the native 55mm backfocus, I'm wondering if I need reduce the backfocus as I lengthened it in this image and got some strange stars in parts of the image.  Maybe a bit of tilt too.

[Zummerzet_Leveller]

1 hour ago, simmo39 said:

Wow, that is a great work. You seem to be banging them out at the moment. I gave up on the M81 M82 image, just couldnt get it right and to top it off I now have an LED street light ove my garden! but as they say no pain no gain.

Thanks for the comment Simmo.  That's not great news about the LED street light.  There are few threads on here about street lights and asking the council to shield them if the light is causing a nuisance, worth a scan through when you have time.  You may be able to get the council to reduce the impact. 

[Astroscot2]

14 hours ago, Zummerzet_Leveller said:

Thank you for the comment, slightly bigger FOV with the 2400 which would work nicely to get M35 in, I think I would have struggled with the 2600.  How do you find the stars in the corners of your images with the SpaceCat and the full frame sensor on the 2400?  I've been struggling with a bit of coma at the native 55mm backfocus, I'm wondering if I need reduce the backfocus as I lengthened it in this image and got some strange stars in parts of the image.  Maybe a bit of tilt too.

Well I noted my sig was incorrect! I too have the 2600mc....    With my framing I cut out the bright star Tejat which looking at your image means ive sacrificed the interesting part of the nebula to shoehorn in M35?   Less would have been more.

Regarding the spacecat, I only recently noticed that if you release the focus lock too much which I did due to using an EAF for autofocusing , the whole front lens assembly can wobble which can give dodgy stars, otherwise im quite happy.   Not sure the 55mm back focus needs to be that precise with a Petzval ?

Mark

[Zummerzet_Leveller]

On 14/03/2023 at 11:40, Astroscot2 said:

Regarding the spacecat, I only recently noticed that if you release the focus lock too much which I did due to using an EAF for autofocusing , the whole front lens assembly can wobble which can give dodgy stars, otherwise im quite happy.   Not sure the 55mm back focus needs to be that precise with a Petzval ?

Thanks Mark.  Yeah you would think that backfocus shouldn't be an issue with the Petzval design but my stars in the corners are not great, worse with a filter.  Could be that I have a duffer.  If the clouds ever clear again I'll play around to see if I can improve them.