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Horsehead and Flame Nebulae, and the Ghost of Alnitak (Grrrrr!) 17 Nov 2020

Started by The Thing, Nov 20, 2020, 19:05:29

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The Thing

Perennial favourite for the time of year. Shame about the Ghost, it's a nasty doughnut and I could have a go at making it less obvious but it would probably introduce worse nasties. It's most likely caused by a reflection off the Optolong l-Enhance filter.

46x240s Gain 120 Offset 4 Temp -5c

Image date, time and location:   2020-11-17, 04:00CET (mid), Manche, France
Telescope aperture and focal ratio:   TS1506UNC Newtonian,, GPU Komakorr corrector
Camera and filters used:   ZWO ASI294MC Pro, Optolong L-Enhance dual band filter
Processing applied:   Pixinsight (EZProcessing), Darktable




Carole

That's a really nice image Duncan, pretty noise free, and nicely processed.

I see what you mean about the ghost, very annoying.

Pixel peeping there is something going on with the star shapes.  Left hand side there is a small "star" sitting on top of every star, but on the Top left the extra star sits at about 1 o'clock and on the right side bottom the stars are elongated.  I think this might all be down to coma/spacing?  But who am I to talk it's taken me years trying to deal with tilt and get the spacing right. 

If you don't zoom right in it is a lovely image.

Carole


Roberto

You have done really well!  You could easily crop the image to remove the reflection and it would still be top quality.

Roberto

The Thing


NoelC

Lovely bit of sky and beautifully captured.
Well done Duncan.
Didn't notice the ghost until I zoomed in - I guess there's nothing you can do about it at that FOV?

Noel
Swapped telescopes for armchair.