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andyc
29-04-2015, 11:06 PM
Well it's been a long while between photos! A mix of bad weather and dodgy health (nothing dramatic) has kept me from the skies, but at last this week I managed to get under some clear skies with the scope. Even managed to remember how to set it up and got the guiding going OK. The skies were awfully teasing with stratocumulus rafts and a quarter Moon for two nights, but mostly clear last night :D

The southern Pinwheel, M83, 15 million light-years away in the constellation Hydra.

- 130 minutes of exposure at ISO800 (26 x 5 mins), 150mm Newtonian, EOS 60D, HEQ5pro, guided, darks, flats and bias subtracted. Processed in PixInsight and Photoshop.

A larger version of the wide view (http://www.pbase.com/andycasely/image/159888507/large)

Larger version of the closeup (http://www.pbase.com/andycasely/image/159888504/large)

Had some issues with DBE producing quite grainy images (lots of black pixels?), so in the end I skipped the step - so the background is a bit uneven.

astronobob
29-04-2015, 11:28 PM
Considering time between sessions, you gotta be happy with that Andy, stars look very round, nice colours and detail, its all there :thumbsup:

sil
30-04-2015, 07:23 AM
I'd be happy to get that, lots of structure.

kosh
30-04-2015, 07:16 PM
Quite nice Andy!

cometcatcher
30-04-2015, 11:47 PM
That's a beautiful image!

Camelopardalis
01-05-2015, 08:18 AM
Nice one Andy :thumbsup: your perseverance has paid off, hope all is well.

Flugel88
04-05-2015, 05:46 AM
Some nice detail in there Andy Worth dodging the clouds for.

raymo
04-05-2015, 12:36 PM
Very nice Andy, but I notice that you have the blue gradient in the
bottom half of the image. Cometcatcher posted instructions for
eliminating gradients in his reply no.11 to my current post of NGC 5128
[Centaurus A]. Maybe you could make a fine image even finer.
raymo

andyc
04-05-2015, 10:27 PM
Thanks everyone! Am pretty happy with the result.



Hi raymo (and thanks too!), I was well aware of the gradient, my battles with PixInsight's DBE just weren't quite producing the result I wanted. I left it out in the end so that I could simply get an image out! Subtracting the DBE background left quite heavy fine-scale noise (with many black pixels), though a flat broad-scale background. The image is much prettier with the broad gradient and smoother fine-scale structure. I have a couple of plans to get the DBE working better when I have time. I'll have a play with the background in Photoshop as you suggest, but it's probably more effective if I can get DBE working as it will be within my initial processing workflow - fewer unnecessary file/program conversions. All part of the fun!