Yet another Eta Carina

[acotiga (Andrei)]

Here is my first take at the Keyhole and Carina nebula.

Time: 36 x 2.5 min @ ISO 800, Canon 350 unmodded, darks, bias, no flats
Telescope: 8" f5 Starwatcher reflector on EQ6 mount
Guider: QHY5v on 80/400 Starwather doublet
Location: Christchurch, NZ, Canterbury Astonomical Society Observatory

It's a bit washed out as the moon was rising for the last half of the shot set. I had to crop the image pretty drastically as the coma was really annoying due to the rich star field.

[rustigsmed (Russell)]

Hi Andrei,

I really like the colours!

You weren't kidding about the coma, does that seems a little excessive for a cropped version for an f/5?

i'm not sure, someone on here would know better than i ...
sorry coma is fresh on my mind, i just photographed almost the same shot of eta carina the other day, have a f/5 and straight afterwards purchased the baader MPCC and trying to sort that out.

best of luck

Russ

[acotiga (Andrei)]

Thanks Russ. In hindsight, I think I’ve done a boo-boo and forgot to secure the focuser. This would actually explain the off centre slight vigneting that I had, due to focuser slop. The other pictures do show coma, but not that bad. First I atributed it to the rich starfield which might have had exacerbated the effect.

I don't know…I'll shoot it some other time probably, but definitely not soon. For my first try on it I’m content.

Has your MPCC arrived yet? Have you had a chance to try it? From what I've read it should be a straight forward job cor a DSLR. I'm however worried about mine as I shortened the tube to make room for a flip mirror.

[rustigsmed (Russell)]

sounds like you've got your problem sorted.


yes, the MPCC, arrived this week. yesterday day, blue skies and light winds by evening very windy and clouds closing in.

still set up the scope, and had a quick crack at it. i couldn't reach focus on the larger spacer provided (needed to go inward more) but could on the smaller spacer provided. I am not sure if its enough distance between the CC and the camera sensor as the wind effected the images.

on one of the 'more clear' photos it looks like its improved but perhaps still some coma around (only looked zoomed in on the DSLR screen). i need to get back out and have another play fiddle. hoping i don't need to adjust the scope. if so it'll await my new setup which should be up and running in a couple of months (eq rather than alt azi).

i'm sure its simpler than this, i've just been reading so many threads on what to do, i think i went back a few steps in understanding from where i was orignially.