NGC5367 - a comet in interstellar space

[tim.stephens]

Still a work in progress - I'm going to try and acquire more luminance data tonight if the weather gods are feeling nice. BUT I'm happy enough with the results so far.

This is was taken over ~3.5 hours last night:
2 hours luminance
20/30/45min RGB 2x2 bin
Astronomic 2c
Explore Scientific ED80 triplet (from Glend! Thanks Glen!)
Orion field flattener
Atik 428ex
xagyl motorised FW
Orion TOAG and QHY 5l-II

I'm really loving the small APO scopes. I can set up all my gear in 15 minutes and two trips AND I don't have to be that careful with polar alignment (still, have my legs marked on the concrete, I just don't have to drift align in PHD2).

Fantastic!

Hope you enjoy. Still a novice imaging processor - does anyone have tips for removing noise from RGB channels when stretching (apart from the obvious, shoot more RGB)? I tried 2 and 3 drizzle in DSS but not a huge improvement.

Larger Astrobin here:
http://astrob.in/249127/B/


Tim

Edit: for those interested, there is a shift in the focal point of these RGB filters when used with this refractor/FF combination but the difference is very subtle and I didn't notice it at all on the FWHM measurements on subs. The difference is quantifiable using a bahtinov mask but again, only minor and worst on the blue, as others have reported. Doesn't seem to be a need to refocus on filters IMHO.

The Astronomic 2c are parafocal on my RC8.

[Atmos]

Looking good Tim! You could possibly push the saturation a bit more but that is just a personal taste :)

Almost all refractors will have some focus difference between some filters, usually in blue as you have noted. I also get some shift between different 3nm narrowband filters :)

[tim.stephens]

Right! First thing I checked when I had the scope out under the stars was the focus point for each filter. I guess I've been spoilt a little with the RC8, once focused in a session it rarely needs a tweak.

Just on the topic of focusing... for a bit of fun, I made a DIY motorised focuser (Arduino with temperature) and mounted it to the stock GSO crayford. Bit of a disaster as the stepper motor I used didn't have enough torque to move the crayford, as this needed to be tightened to support the imaging train.

Bought a moonlite from Ron about a month back and only just found the time to build a mounting bracket. Works a treat and I'm getting predictable and normal V curves in SGP now. I'll keep an eye on it over winter but we've had some cold nights here from warm days and I haven't noticed the focus shifting. This is a steel tube RC8 too.

Don't think I need to fit a focus motor it to the ED80... or do I?

Clouded out here too :-(

Tim

[Retrograde]

That's a really nice shot. Looks like you are on the right track :thumbsup: