Date: 20 July 2017
Location: Green Bank Radio Observatory, WV
Object: NGC 7000 North American Nebula
Camera: Nikon D5300
Telescope: Orion ST-80
Accessories: N/A
Mount: Celestron Advanced VX
Guide scope: Orion 50mm Mini-Guide Scope
Guide camera: ZWO ASI 120MM
Subframes: 24x360s, ISO-1600
Darks: 9
Biases: 20
Flats: 20
I also did a configuration change - I moved my camera up to the Borg and put on my own Orion 50mm guider, since there are some summertime nebulae up in Cygnus I need a larger FOV for. While Miqaela was imaging the North America nebula, I was right next door in the Pelican Nebula, taking 10-minute (!!) subframes. I figured I'd snag some darks the next night when it was going to be cloudy. What was really amazing about being out where it was so dark was that I was shooting 10-minute-long frames on an f/6.6, 76mm refractor with no light pollution filter, and my entire histogram was still in the first quadrant. It was amazing.
I didn't have the mini-guidescope on at the time, but otherwise, here is my Borg imaging setup from the second night. My cables were also put away - it's usually a bit messier.
This time, I also swapped power sources - I put the scope on the 7 Ah battery, and the dew heaters on the 17. That worked great - the 7 Ah ran my telescope all night (although it was flashing yellow when we were packing up), and the 17 Ah still had power left in it at the end of the night. Oh, also, I finally did get a field flattener for the Borg - someone on Cloudy Nights recommended one by Hotech, which is a non-reducing, self-centering field flattener for any refractor with a focal ratio f/5-f/8, and it's half the cost of the one Borg was selling. Until I took a set of flats, it stacked really weird in DeepSkyStacker though - like, the bottom of the image was warped, and the red and green channels separated in that region, like someone was pushing their hand up under a blanket made of this picture. I didn't save one with this effect, but I should have, because it was crazy. But adding flats fixed the problem. (For the record, you can't see it in the subframes, so I have no idea what that is all about).
Date: 20 July 2017
Location: Green Bank Radio Observatory, WV
Object: IC 5070 Pelican Nebula
Camera: Nikon D5300
Telescope: Borg 76ED piggybacked on C11
Accessories: Hotech SCA field flattener
Mount: Celestron CGE Pro
Guide scope: Orion 50mm
Guide camera: QHY5
Subframes: 17x600s (2h50m), ISO-1600
Darks: 10
Biases: 18
Flats: 20
I don't see a pelican, but I do see some pretty colors! Hydrogen alpha (the red light) is hard to get with an unmodified DSLR, and after meeting a guy at the star party who modifies Canons, I've started thinking about doing it again. (Well, paying someone else to do it - I'm handy, but I'd probably break it, since it would be my first attempt at it). Modifying it would allow much more of the red light through the camera's color-balancing filter.
After two and a half hours on the North America Nebula, the sky had cleared up some more, so Miqaela finally got to image the photogenic Andromeda Galaxy, and she got a great image!
Date: 20 July 2017
Location: Green Bank Radio Observatory, WV
Object: M31 Andromeda Galaxy
Camera: Nikon D5300
Telescope: Orion ST-80
Accessories: N/A
Mount: Celestron Advanced VX
Guide scope: Orion 50mm Mini-Guide Scope
Guide camera: ZWO ASI 120MM
Subframes: 21x300s, ISO-1600
Darks: 9
Biases: 20
Flats: 20
One drawback of shooting through the Orion ST-80 is that it's an achromatic doublet, meaning that there is chromatic aberration. Since it's more meant to be a terrestrial viewing or guide scope, this isn't usually a problem, but for deep sky imaging, you'll start to notice. It also has some coma. In the case of the Andromeda image, the central stars turned out more red and the outer ones more green. We may be able to process that out, but I don't quite know how yet. Despite that, however, I think her images came out great! Definitely better than my first year's worth of astro images - although it helps to have someone coaching each step, rather than my stumbling through reading forums, books, and getting bits and pieces of a variety of people. :) Of course, it can sometimes be the blind leading the blind here, since I haven't been at it for very long myself!
My second target for the night was the Eastern Veil Nebula, something else I've imaged before but it turned out very dim in my Orion ST-80 only taking 1-minute frames last August from my decidedly less dark home location (see that image here). This one came out WAY awesome, despite the fact that I only got three subframes before some impending clouds with lightning made us decide to go to bed.
Date: 20 July 2017
Location: Green Bank Radio Observatory, WV
Object: Eastern Veil Nebula
Camera: Nikon D5300
Telescope: Borg 76ED piggybacked on C11
Accessories: Hotech SCA field flattener
Mount: Celestron CGE Pro
Guide scope: Orion 50mm
Guide camera: QHY5
Subframes: 3x420s (21m), ISO-1600
Darks: 10
Biases: 16
Flats: 20
Sometime, I'm going to piggyback my DSLR with like a 200mm focal length lens or something and get the entire Veil Nebula/Cygnus Loop. That'd be awesome!! The Veil Nebula is a supernova remnant from a supernova that happened somewhere between 3,000-6,000 BC. It's about 1,470 lightyears away, and the whole thing is about 100 lightyears across now. It is bright enough to see in a telescope too - I looked at the Eastern, Western, and even the central portion known as the Pickering triangle through a 12-inch Dob with an OIII filter. It was incredible! I was so glad to get to see it at last! It jumped right out with how dark it was up at zenith.
We went to bed at 4:30 AM again after taking a little more time to secure the tarps over our scopes and make sure all of our other stuff was away in tubs. It's a good thing we did too, because it rained like crazy that morning and throughout the day! A little water got into my accessory 3-drawer bin (which mostly contains screwdrivers, cables, and cleaning tools), and into Miqaela's empty mount box, but otherwise everything stayed nice and dry.
We were basically the only ones at the entire star party who stayed up all night (and definitely the only women), so sleeping late was difficult due to people talking loudly at 7:30 AM, but we managed to get enough sleep to continue to function the rest of the weekend.
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