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View Full Version here: : Never image on Friday 13th! And another green thing!!


DiscoDuck
14-05-2016, 03:32 PM
I made the mistake of imaging on Friday 13th!! :)

All sorts of issues, e.g. I tried to "fine tune" my polar alignment and ended up way out. Also the CCD was filthy so cleaned it (twice!!) and still ended up with rubbish on it.

Ice formed on the rubbish during the session and so the flats couldn't remove it fully - hence the drastic crop of the image attached, resulting in the Cinemascope style aspect ratio, as I had to take out the whole top bit. Some Photoshop spot healing done too in the top left to remove residual dross - so my apologies for a heavily photoshopped image. There's probably a couple of stars missing that should be there - think of it as an anti-nova!

In spite of the Cinemascope look, it is far from a blockbuster image!! And I mainly put it up to ask if anyone knows what the small faint green area is about a third of the way down on the right hand side. It's definitely in the subs (just can make it out with an extreme stretch). But cannot see anything similar on an APOD image I checked. Any ideas? I don't think for a moment it's a discovery - just another Friday 13th problem I haven't worked out yet!! Maybe the same UFO that photobombed Mark's image?? :)

Anyway, after that long waffle, image of NGC 6729 (and 6723) - 17x20 mins QHY8 OSC on an RC8 scope - attached and also on Astrobin (http://www.astrobin.com/248959/). Needs more data (without ice ideally!) as this is from the 'burbs and so struggled with noise as well.

Thanks for looking.

Paul

Atmos
14-05-2016, 03:42 PM
It looks like you have some really nice data there Paul! You have also answered why last night was so terrible for me!! Didn't think that Friday the 13th would have caused so many issues but I managed maybe 3 hours of usable data from 8 hours of attempted imaging :P

It looks like you have been a bit heavy handed in the noise reduction (looking at the nebulos regions) but it's good!

DiscoDuck
14-05-2016, 03:47 PM
Thanks Colin. I don't think it's excessive noise reduction in that nebula - more the opposite as I think it was oversharpened when it had too much noise for the tool I was applying (high pass filter in Photoshop). But, as I said, hope to get more data. Minus ice and green things!!

multiweb
16-05-2016, 09:37 AM
Nailed it! This is unbelievably sharp. Well done. :thumbsup::thumbsup::thumbsup:

spiezzy
16-05-2016, 01:51 PM
well i think it is frigging AWSOME

gregbradley
16-05-2016, 02:23 PM
Very nice. The green spot looks like some sort of reflection halo.

Greg.

Bart
16-05-2016, 02:24 PM
More data will only enhance it, it is quite nice already.:)

DiscoDuck
16-05-2016, 06:45 PM
Thanks Marc.



Glad you like it :)



Sounds reasonable. But why green?? It's clearly green in the subs too. Reflection issues I've had before tend to be white.



Thanks Bart. Gotta wait till the next new moon now I guess :(.