4 replies to this topic

[JustAKidWithATelescope]

I took this in LA Bortle 7 sky
Subs:
150 x 2 min.
Equipment:
Eq Mount: Eqal55i pro


Telescope: Nextstar Evolution 8


Camera: Sony A7r111


Guide camera: asi 120mm guide camera


Guide scope: ZWO - 30mm f/4 Mini Guide Scope - 30F4


Accessories: Field flattener, ASAIR, Dew Shield.
Processing: Siril, Lightroom

 

Please check out the video:

Video: https://www.youtube....rts/EgSSlAxmXU4
or

Just the Image: https://app.astrobin.com/i/s2svgm

[UP4014Fan]

Looks pretty good, although I think your focus might be a bit off.  

 

Are you taking flats?  Looks like there's something in the lower right of your image.

[Northrim]

I would agree with UP4014Fan.  The focus seems a bit soft,  also you seem to have either tilt or imperfect backfocus.

[smiller]

Nice first ring nebula.  I don’t have much advice but perhaps a few thoughts and questions:

 

1) What method do you use to focus?

 

2) I noticed some coma especially the upper right.  Since it’s uneven perhaps there is a bit of tilt and it may be tilted away in that corner.  If so, straight if it up would at least even it out a bit.  I notice you have a field flattener, but I’m not familiar with that scope and what star quality should be expected with a full frame camera.  That’s a big sensor and every scope has its limits.

 

3) From, B7 you would certainly benefit from a dual narrowband filter on those emission nebula even with an unmodified camera.

[Peter Morrison]

The soft focus is most likely caused by mis-collimation.  All stars are comet shaped with the head pointing to the bottom left.  It looks worse in the top right which might indicate tilt, but work on collimation first.

 

Peter

Edited by Peter Morrison, 17 June 2025 - 05:48 PM.