The Smokin' Hot Galaxy - M82

[powerlord]

The cigar galaxy ! - see what I did there... 😚

Shot with SW 300PDS, Baader mk3 CC and asi2600 over the only 2 clear  nights in the last month!

So at the moment, 7 hours of 10 min subs. The plan is to next add a night of Ha, and if the weather gods are kind, maybe another 2 nights or so of RGB and enter it into the comp.

But for now, I'll share what I have so far. It's already better than any M82 I've shot before - so hopefully can get even better.

At this scale, guiding is king - At the end of the day I've got a massive telescope (and with a foot of dew shield on the end, it's around 12+ feet high on the mount), guided by an EQ6-r, with 20kg hanging off the balance bar*. So it takes a bit of balancing, and a fair bit of tweaking to keep the guiding RMS well under 1". And since I'm at about 0.52" per pixel I need very good seeing AND guiding RMS <0.6" to get good subs. Luckily that EQ-r has always been the best of the two, and I only had to throw away a handful of subs. And unlike last month's data of M101 - which just wasn't good enough seeing for most of it to be worth integrating, these 2 sessions have been worth it.

Anyway, without further ado, here's what I've got so far. It's starting to get filled with lots of faint wee galaxies everywhere too, which is nice.

stu

original:

 

re-edit after Olly rightly pointed out I'd somewhat lost the plot with the colours:

 

Obviously I'm really missing the Ha - and it's a target that demands it - so here's hoping for some clear skies!

 

*I can see me being found one day having been dead a week under this thing and the police report working out - "we assume he must have been trying to single handedly lift up the 25kg 6 feet tall telescope by himself and trying to balance on this here step ladder on one foot while holding it over his head to attach to this mount thingy, lost his balance and been smacked in the head by the telescope on landing. Luckily we found his dog before it starved to death...

 

Edited April 20, 2023 by powerlord

[ollypenrice]

The whole image is very red. Indeed it looks fairly monochromatic brown. This is a surprise because the 2600 OSC chips I use tend to be colour cold. Are you using some kind of LP filter? It might be productive to look into what's subduing your blue and green channels.

Olly

[ONIKKINEN]

Pulling some really nice detail from the core here! Im amazed your setup handles the 300PDS so well, it just seems like way too much scope for the modest mount but clearly it has worked.

[powerlord]

16 minutes ago, ollypenrice said:

The whole image is very red. Indeed it looks fairly monochromatic brown. This is a surprise because the 2600 OSC chips I use tend to be colour cold. Are you using some kind of LP filter? It might be productive to look into what's subduing your blue and green channels.

Olly

Hmm. it didn't on the calibrated monitor. But yeh I agree.

the channels are balanced and the background is neutral though. No filters other than inbuilt.

I'll have a look - maybe chuck it through Siril's photometric calibration. stay tuned...

[powerlord]

right - you know that way you get focused on bringing out the details, composition and totally forget the colour balance..

so - this needs starting again. rather than delete post, I've just deleted the image for now. I'll update tomorrow when re-edited.

 

[ollypenrice]

7 minutes ago, powerlord said:

right - you know that way you get focused on bringing out the details, composition and totally forget the colour balance..

so - this needs starting again. rather than delete post, I've just deleted the image for now. I'll update tomorrow when re-edited.

 

There was nothing wrong with the details, they were great. A good test of image colour is to check the spectral class of the stars in a catalogue. If the OB class stars in an image aren't blue - they should be!

Olly

[powerlord]

3 hours ago, ONIKKINEN said:

Pulling some really nice detail from the core here! Im amazed your setup handles the 300PDS so well, it just seems like way too much scope for the modest mount but clearly it has worked.

yeh it does feel a bit precarious - but it's guiding in the 0.5" rms area so can't complain. Now I'm playing with it more, I'm learning when it makes a difference and when it's not worth the bother. With average seeing, it's fair to say it doesn't add a lot more than my 200pds. But when it IS good seeing, it really does show its colours (sic)

stu