M51

[Mark_C]

Hi all,

Had an extensive break in the weather last night which managed to bag me 71 x 300s exposures on M51 with an additional 15 x 300s from a previous session. This was imaged at 2800mm @ F10 with a Celestron Edge HD 11" on a ZWO AM5 mount using a 2600MC. Image was software binned in Pixinsight 2x2 and optimised with BXT and NXT.

Conditions were quite difficult as the first part of the night was slightly breezy and of course at this FL guiding can be a pain, but it calmed down later in the night and am very happy with the results.

Overall pleased with the outcome and am really enjoying imaging at this focal length, it's possible to frame some really small objects. F10 is a bit of a pain but absolutely workable if you have dark enough skies (I'm currently in a B4 area).

Next target is M101!

 

 

[Icesheet]

Fantastic result and I'm amazed the AM5 is carrying that beast with such results!

[saac]

Cracking image there Mark. 

Jim

[Mark_C]

Thank you for the positive feedback, I really appreciate it! 😀

Absolutely delighted with the AM5, it has exceeded expectations and makes a very nice setup as both the scope and mount are highly versatile! Never would have expected this setup to work but it handles the C11 with no issues at all! I am now wondering if ordering the 0.7x reducer for the C11 is actually worthwhile as so far these results even at F10 are nothing short of fantasic.

The only issue I sometimes find is finding a decent guide star but it does help tremendously in having an OAG-L with a larger prism and an ASI174MM attached, that larger sensor really makes a difference!

[900SL]

Superb image, very detailed!

[assouptro]

On 08/03/2024 at 05:08, Mark_C said:

Thank you for the positive feedback, I really appreciate it! 😀

Absolutely delighted with the AM5, it has exceeded expectations and makes a very nice setup as both the scope and mount are highly versatile! Never would have expected this setup to work but it handles the C11 with no issues at all! I am now wondering if ordering the 0.7x reducer for the C11 is actually worthwhile as so far these results even at F10 are nothing short of fantasic.

The only issue I sometimes find is finding a decent guide star but it does help tremendously in having an OAG-L with a larger prism and an ASI174MM attached, that larger sensor really makes a difference!

Great image Marc! 

I know what you mean regarding the guide stars at that focal length especially around m51! 
(I have a 12” Meade which I use at 2084mm with a Starizona reducer/flattener)
I was using the Celestron oag until recently, it’s massive prism and ability to rotate was perfect but it eats up loads of back focus and my latest rig hasn’t the space so I’ve resorted to the tsoag9 (my first ever oag purchase around 10 years ago?!) it is really fiddly and doesn’t have the biggest chip but thanks to a rotator I can normally find a guide star 

Imaging at this focal length is great fun, it’s not without its challenges but I enjoy it! Even on large nebula it can be fun to get up close and personal with just a small interesting area and there are many more guide stars around Cygnus and Cassiopeia! 

One thing to consider, re- the 0.7 flattener it will speed up your subs, so less waste due to guiding errors, wind, planes etc so it may be worthwhile in the future? 
 

Anyway, that’s enough waffle from me, going to go back to your image and enjoy 😊

Thanks for sharing 

Bryan 

[tomato]

Very nice, I love the detail and subtle colours.

[Mark_C]

11 hours ago, assouptro said:

Great image Marc! 

I know what you mean regarding the guide stars at that focal length especially around m51! 
(I have a 12” Meade which I use at 2084mm with a Starizona reducer/flattener)
I was using the Celestron oag until recently, it’s massive prism and ability to rotate was perfect but it eats up loads of back focus and my latest rig hasn’t the space so I’ve resorted to the tsoag9 (my first ever oag purchase around 10 years ago?!) it is really fiddly and doesn’t have the biggest chip but thanks to a rotator I can normally find a guide star 

Imaging at this focal length is great fun, it’s not without its challenges but I enjoy it! Even on large nebula it can be fun to get up close and personal with just a small interesting area and there are many more guide stars around Cygnus and Cassiopeia! 

One thing to consider, re- the 0.7 flattener it will speed up your subs, so less waste due to guiding errors, wind, planes etc so it may be worthwhile in the future? 
 

Anyway, that’s enough waffle from me, going to go back to your image and enjoy 😊

Thanks for sharing 

Bryan 

Bryan, thank you for the kind words! Glad to hear from someone else who has also endured the difficulities of long focal length imaging, it really is a wild ride but its well worth it. The M51 is a bit of a nightmare at native FL to be honest, even with the big prism and large sensor, there seems to only be 1 prominent guide star so if conditions aren't great , guiding suffers a lot as multi star guiding is either sketchy or just isn't functional.

The Celestron OAG was one option I had considered as the rotation feature was really attractive along with the big prism, but like you had unfortunately discovered it really consumes a great deal of backfocus which would cause issues with the way my ZWO system is set up. Another consideration was the Askar OAG but I think that has a slightly smaller prism.

Absolutely 100% agree that a reducer is something that I should aquire and should be considered an essential purchase for this scope - not only will it reduce oversampling a little, but like you say imaging at F7 will allow for light collection in a shorter space of time.  The great thing about the APS-C sensors is that there's plenty of cropping potential so lessening the FL isn't an issue. 🙂 

I think the aim for me in this instance was to stretch the limits of what's possible with this telescope on a mount that's not even supposed to be rated for imaging beyond 900mm. 🤣

Just waiting for another long session to arise, doesn't look promising though as weather has been/looks to be awful 😞 and it doesn't help with the nights now rapidly drawing out.

8 hours ago, tomato said:

Very nice, I love the detail and subtle colours.

Thank you, really appreciate it! 🙂

Edited March 13 by Mark_C

[Ags]

APOD!

I was trying a similar shot with somewhat lighter equipment - a HEM15 and C6, but the night was too windy (still learning my way around this new mount). Next year I might move to Bortle 4 skies - looking forward to that after a decade of Bortle 8...