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Atmos
05-08-2016, 10:09 PM
First night out in near two months! Went up to Heathcote for the dark skies, so lovely and dark. Figured that while I was up there I should do something that actually takes benefit of the moonless skies. Had planned on getting a good 7 hours of data on a subject but with a lot of mount issues (the EQ6 just wasn't playing very nice good a good couple of hours) I eventually half gave up with trying to get it perfect and just went with it. Having to get up at 3:30 am to pack up and get back home to unpacked and go to work, wanted to get some sleep :P

So, there is trailing and I haven't even tried to go over 200s. Less than perfect but just happy to be out under the stars :) CCDInspector is currently telling me that I have 0.2mm of tilt, I had planned on working on that, need to do it on a non-work night :D

Link to Astrobin (http://www.astrobin.com/full/258077/0/)

Link to Rework (http://www.astrobin.com/full/258077/B/)

6x200 RGB
50x200 L

No dithering and no calibration.

EDIT: Just ran a whole bunch through CCDInspector and its closer to 0.5mm off. I know I don't need any packers or anything, just a screw driver to play with the focuser collimation screws and an hour or so :P

Placidus
06-08-2016, 09:39 AM
Just the thing! Nicely done. Good colour balance and saturation.

If you find yourself with nothing else to do, Barnard's Galaxy responds very well to an H-alpha filter.

Paul Haese
06-08-2016, 09:42 AM
I really like that field of view on this object. Looks like there is a bit of IFN in the back ground too. Its scattered around so I doubt it is a gradient. Despite your the issues it has come out pretty good.

Atmos
06-08-2016, 10:10 AM
Something I can do from my Melbourne backyard! Thanks MnT :)



Thanks Paul. After the initial stack I wasn't sure if it was IFN or just a mishmash of gradients. As you say, it is scattered so less likely to be gradients. They're very faint, blacker areas are around 1875 ADU while the IFN is just a tad over 1900 ADU. It is a lot easier to see in the straight luminance. The attached image is the raw Luminance.

topheart
06-08-2016, 10:16 AM
Great sense of depth!
Cheers,
Tim

Atmos
06-08-2016, 11:15 AM
I put all 68 files into CCDInspector and from that culled half of my images. Anything with an Aspect over 15 has been removed, actually turned out a lot better overall than I was expecting!

R: 2x200s
G:4x200s
B:5x200s
L:22x200s
So now down to 1.8 hours but MUCH happier with the result.

I ran a Local Histogram Equalisation on the background (256 radius) to enhance the IFN. Processed the stars separately this time, first time around I didn't see the point in putting time into terrible data :P

It is now even noiser than all getup but happier all the same.

Link to Astrobin. (http://www.astrobin.com/full/258077/B/)