Mosaic of 6 x 1-minute panels of the Milky Way from the National Youth Science Camp in the dark of West Virginia.
The camp grounds were awesome - reminded me of the summer camp I used to work at in North Idaho when I was in high school and college.
They celebrated the different countries represented by the delegates alongside the posting of the American flag each morning.
After dropping off my duffel bag in the guest cabin, I drove down to the field where Phil and I would be setting up. The trees were very tall, so we had to strategically place ourselves to be able to see the North Star for polar alignment, as well as the parts of the sky we wanted to look at. We also needed to be near each other because we were sharing power from his generator. I can go almost entirely on battery power, except for my ZWO camera, which I've seen online can be battery-operated, but I haven't figured out exactly how to do it yet. But AC power is nice because then I can crank up my dew heaters and run the cooler on my ZWO camera, and have a 2.4A power supply for my tablet (my cameras drain it if it's only plugged into a 1A power supply). Phil wanted a good view of the western sky since his demo was to look at satellites, which his Paramount running TheSkyX can track. They looked at Iridium satellites, since they commercially publish their ephemeris data.
I brought my Celestron Advanced VX mount, Borg 76mm ED apochromatic refractor, ZWO ASI1600MM Pro camera and Astronomik LRGB filters, and then my Orion 50mm mini-guidescope and QHY5 camera to guide it. I also brought my 8-inch Schmidt-Cassegrain on my Celestron NexStar alt-az mount, which is my visual observing setup that I take to outreach events, since I knew there would be lulls in the astro-imaging activity that could easily be filled by actually getting to look at stuff.
The camp consists of three and a half weeks of lectures, demonstrations, workshops, hands-on activities, and out trips. For many of the daytime activities, there are several offered at once with so many spots available, and the delegates sign up for them on a rotating-priority basis. The program organizer asked how many I would like for my session, and I just picked 20 kind of arbitrarily. I could probably do a more focused study with a smaller group, but in general I like to "share the love" of how amazing the universe is with as many people as possible, and I figured 20 was about as many as I could cram into a circle around the telescope. I checked out how many had signed up for each of the two nights, and the lists were totally full, with people writing their names down as #21, #22, etc to try and fit! I told the program organizer that I'd pretty much take whoever wanted to come down. Usually lights-out as at 11 PM, but Phil and I got permission to go until midnight, with the option for some of the delegates to leave at 10:30 PM (mainly so that they wouldn't be trickling into the cabins and disturbing their sleeping cabinmates multiple times).
The staff and guests had access to wifi if you stood closer enough to the office building (there was no cell service to speak of), so I checked the forecast. It was incredible! We got so so so lucky. No clouds in sight!
After dinner, Phil and I hung out down in the field to finish getting set up while the delegates were at an after-dinner lecture, and then they came down at 9:15. Shortly after 9:15, the delegates arrived, and clustered around my table and telescope as close as they could, super excited about the demo. The first step was to align. I wanted the students to participate in the acquisition of the data, so I had them take turns slewing the scope to get the star in the center of the image. I had done the first one so that I could get the camera focused. It was funny to see their reactions to how an equatorial mount moves - "It never goes the way I think it will!" - yessss, welcome to astrophotography! It didn't help that the way I had the Borg scope set up the first night was still on its little wooden dovetail, which is too short to move it far enough forward to balance the weight of my camera hanging off the back. At the Texas Star Party, I fixed this by duct-taping two waterbottles and a pair of binoculars to the end, but I forgot about that particular problem before I headed down, so I had none of those things. Because it was not at all balanced in declination, the dec axis had a hard time slewing, and had a fair amount of backlash.
After aligning, polar aligning, and aligning again, it was finally time to take some images. I also had the 8-inch going this whole time, so students could peel off if they were bored and go look through the scope. It was so dark that I had a whole treasure trove of targets available, even though basically the entire Milky Way and none of the planets were visible due to the high tree line. Nonetheless, we looked at M51 Whirlpool Galaxy, globular cluster M13, and several planetary nebulae, including M27 Dumbbell, M57 Ring, and the Cat's Eye Nebula. Due to the lack of visibility of good Milky Way targets, and the fact I was using the wide field-of-view Borg (1.5 x 2 degrees), I had to choose our imaging target carefully. I also needed it to be bright enough to be exciting in the subframes. I settled on M51 Whirlpool Galaxy, up off the end of the handle of the Big Dipper. After PHD finished calibrating, I took our first subframe with the luminance filter at a little after 11 PM. Boy it looked great! The delegates were duly impressed.
It looks over-saturated, but it's not - that has to do with how the raw FITS files are viewed.
Subsequent frames streamed in, and everything looked good. At midnight, it was time for the students to turn in, but the skies were still incredibly clear, and the Milky Way was at last getting above the trees, so I decided to stay out.
Once the students had left, I switched filters to the red filter, but the guiding was starting to degrade, and all of the frames were turning out poorly. I knew it was because declination was out of balance. I had tried to find a Vixen dovetail to attach it to, but couldn't find anything that was long enough, or that had countersunk holes for the screws, since the bottom of the dovetail needs to be flat in order to fit into the dovetail slot on the mount. I have two long Vixen rails, one for my 11-inch SCT and one for my 8-inch SCT for putting a guidescope onto that I use dovetail clamps on, but they're the wrong polarity - it's perfect for sitting on top of a scope, but it won't go into the dovetail holder on my mount in that orientation, and if I flip it over to fit, then the dovetail clamps are the wrong way. I have been pondering this problem for months, and am amazed that I can't find a dovetail that works, it's not like I'm connecting anything weird to anything else weird, just a refractor to a mount, a very standard setup.
Finally, inspiration struck, as it can when one is sleep-deprived: I could remove the wooden dovetail so that I could move the rings closer to each other, and then attach it to two of the holes near the end of the dovetail rail for my 11-inch SCT. Then, I could set it all the way forward, where the screws holding the telescope clamps in place would be outside of the actual dovetail holder on the mount, but having it this far forward would probably be exactly what I needed for balance. Now, I didn't have any 1/4-20 bolts that were short enough, so I had to use a couple of washers to get some extra distance. So I performed some midnight field surgery on my setup, hooked everything back up, and voila, I was able to balance!
Also, the pads rubber-banded to the top are hand warmers - I only have one dew heater controller, and I didn't want to have cables running between the imaging setup and the visual observing setup, so the dew heater controller was over with the 8-inch, since it has a far greater need for dew resistance.
Once all that was done, M51 was getting fairly low and in the mush, and the Milky Way was nice and high, so I decided to image a target that is best done under dark skies with a refractor: the North America Nebula. By this point, it was about 2 AM. I took 5-minute subframes, and guiding was looking a lot better. Not phenomenal, but good enough for a wide FOV refractor.
The subframes didn't reveal much, but I didn't expect them to, since it's a large and diffuse nebula. Only stacking would tell me how well it was going to turn out. And turn out nicely it did! At least, with just the luminance - I definitely didn't have time to get a full set, but I did manage to get 7 subframes before I called it quits and went to bed.
Date: 8 July 2018
Location: National Youth Science Camp, WV
Object: NGC 7000 North America Nebula
Camera: ZWO ASI1600MM Pro
Telescope: Borg 76ED
Accessories: Hotech field flattener, Astronomik LRGB Type 2c 1.25" filters
Mount: Celestron AVX
Guide scope: Orion 50mm mini-guider
Guide camera: QHY5
Subframes: L: 7x300s (35m)
Gain/ISO: 139
Stacking program: DeepSkyStacker 3.3.2
Stacking method (lights): Media kappa-sigma clipping (2,5)
Darks: 20
Biases: 30
Flats: 0
Temperature: -25C (chip)
I finally climbed into bed and passed out at around 3:30 AM. A night well-spent! Unfortunately, I had forgotten my sleeping mask and earplugs, but it was chilly enough that night that I just pulled on my knit hat over my eyes. I figured I'd probably wake up with everyone else, and then once they got out of the cabin, I could sleep a few more hours and miss breakfast.
'Twas not to be.
At 7 AM, orchestral music blared out of the camp's PA system.
I want to wake up in the morning
Where the rhododendrons grow
Where the sun comes a-peeping
Into where I'm a-sleeping
And the songbirds say "Hello!"...
nooooooooooooooooooo
And then the song finally ended...
And stay here in West Virgnia
Where the rhododendrons grow!
All right, back to sleep.
Nope! Another 30 minutes of music to make sure that all of the campers were not doing what I was trying to do. So I gave up and got up and trudged to breakfast. Luckily, I've discovered I operate pretty well on little sleep, and I was already running a sleep debt from Friday and Saturday nights. Multiple cups of coffee were in my future.
So far, so good!
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