Back imaging after a break while overseas, and with a gear re-shuffle, so time to share a couple of shots. Preliminary processing only, I am waiting for the dirty weather to give me time to do some more.
NGC253 imaged 29th October, from the backyard. 9 exposures of 600 seconds each. Coma from the f4 scope, but this is now sorted with the Baader MPCC that arrived yesterday.
Helix from last night, 30th October, and the coma corrector really works. 10 exposuers each 600 seconds.
Both with the homebrew 8" f4 newtonion, riding on the AP400GTO, and with the SBIG ST2000XCM. Seeing was less than ideal for both, but you take what you are given.
Nice images! What exactly is your homebrew 8" f4??? Did you grind the mirror or is it sourced from somewhere. It looks like its going to be a great scope for imaging!
Hmm, by homebrew I meant I built it up, but no, I didn't grind the optics.
They are GSO mirrors, I simply built the tube (rolled it from 1.3mm alloy), made a spider/secondary holder, and also a primary cell.
Focuser is a Feather Touch, with motor, so as soon as I work out how to use FocusMax, hopefully I will have auto-focus.
Nice Gary. Both of them. I like the detail in 253.
A question though about the star spikes. Are the vanes on your spider offset as the star spikes aren't equidistant around the stars or equally sharp. In the Helix image you have clear spikes only coming out of the bottom of the stars (and less than 90 deg to each other) and the top pair are blurry. In the 253 image it is different with the spikes out one side wider than 90 deg and the other side showing short multiple spikes?
Can't really see them in the Helix shot, and maybe this is as a result of the coma corrector, or perhaps just not as many bright stars.
The 253 shot didn't have the coma corrector, and also has brighter stars. If you look at the shot of the front of the scope you will see why they are rounded and non-equidistant. The budget option for the spider will be the reason.
Thanks team.
yes, the baffles are a copy of the old Intes Micro style, and I have them on the 10" as well. Work? Hope so, as the effort put in should have something to do with it. I reckon they do though.
The spider vane was simpler than doing the four way thing, and it seems to work OK as well.
The camera isn't all that big, unless you are a Starlight Xpress owner. It is better than a smaller c amera and a separate guidescope.
Thoroughly enjoyable renditions of these two objects Gary. Not sure what went wrong with some of the stars on the NGC253 image. Some look like its a blooming problem, yet they do not spike. Look forward to seeing more. Well done.
At this stage Jase I am putting it down to a lack of coma corrector, an over-abundance of coma, and the curvy secondary holder I dreamt up.
I have a series of NGC1365 from last night so will see what they look like.
Gary
Nice work Gary! Like that helix one exp! good to see some of your images again!
Looks like a nice job there of your homebrew 8". Will be making up another one soon myself hopefully with less faults than my current one.
With your curved spider, maybe it is not curved enough causing those spikes? I think you would need to have a 2 vane spider curve a total of 180 degrees (90 degrees each vane) to spread the diffraction pattern a full 360 degrees so no bright spots, spikes show..like the protostar one in the link.
cheers Gary
Nice work! You’ve grabbed a couple of beautiful images there. The detail in NGC253 and the colours in the Helix are gorgeous. Looks like you’ve mastered that one shot colour camera – well done!
I just bought a ST2000XCM so it's good to see what they are capable of on familiar objects. The Baader MPCC is a great piece of gear ay ! I've never looked back since I bought mine for my newts.
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Both of them. 
I like the detail in 253.
