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Adventures in Variable Star Observing

Despite the temperature last night, I decided to get my telescope out and try to hit one of the targets for Exoplanet Watch's January observing campaign (XO-6b). Of course I didn't even see it, with or without my telescope, but no venture is ever a failure, just another learning experience. Last night, I learned A LOT.

My normal setup for deep sky observing is my Celestron NEXSTAR 130SLT computerized telescope, which is a 130mm Newtonian telescope (I call her Newt). She has an aperture of 130mm, a focal length of 650mm, and a focal ratio of f/5. Rather tan load it up with 8 AA batteries (which I've found gives me less than 5 hours of working time), I connected it to my Celestron 12v PowerTank. I popped in a 9mm eyepiece, which is closest to my NexImage Burst camera with the 13.1mm nosepiece, so I have less fine adjusting when I switch over. I mounted the StarSense AutoAlign and connected it to my computer by USB cable from the handheld controller; using the CWPI software I use this to align my telescope, then calibrate and re-align it. After it's aligned, I can then use either the CWPI software or Starry Night to control my telescope and point it at what I want to observe. Once I know everything is visible and aligned correctly, I swap out my eyepiece for my NexImage Burst and I'm off to the races!

If all goes well, that is. Last night, nothing went well.

First of all, despite the 2 to 3mph winds (pretty still), it was 40 degrees Fahrenheit. I am no longer made for cold weather, and I'd already nursing a runny nose the previous week. The only thing that kept me going was the promise of getting my first variable star data to run through Exoplanet Search's EXOTIC program. But hey, my soda remained chilled, bubbly, and fresh-tasting!

I knew going into this that my current location wasn't ideal. I moved out of the city last fall that I'd have better viewing at my new place, but what I didn't anticipate was that no matter where I set up my equipment, there was always a streetlight in my scope's field of view. I did manage to get it set up in just the right spot so I only had to contend with one streetlight, but it wasn't until later into the evening I realized that one streetlight was in the same general area as XO-6, and with an apparent magnitude of 10.20 I wasn't gonna get to see it at all. (But I didn't learn that until later into the evening.)

Next was aligning and calibrating. The StarSense AutoAlign is super groovy and takes about 10 minutes to get the job done, but it's not perfect. Once the initial align completed I needed to calibrate by centering on an object then syncing it back to the software and running the alignment again. The problem I ran into was my setup-my computer was about 5 feet from my scope (I didn't want the computer's glare to influence my view), so I was constantly moving back and forth to look into the eyepiece then use the computer to slew my scope. It was tiring and took a LOT of time. By the time I got everything aligned and ready to go, I'd wasted over 2 hours, and it was really freaking cold.

When calibrating, I centered on one of the brightest objects in the sky-Jupiter. Once everything was aligned I swapped over to my camera and had to fine-tune the view because of the difference between the camera and eyepiece. I opened up my standard capture program, iCap, and had at it. Unfortunately, I hadn't had my scopes out since last summer and totally forgot how to work the freaking software, and had to change all the settings since my computer had been reformatted since then and I'd lost all my previous settings. So that took another 20 minutes. I did manage to get an OK picture of Jupiter considering Newt isn't my go-to scope for observing planets (that would be Maks, my 90nn Maksutov-Cassegrain telescope).

Then I switched over to SharpCap, a program that will not only capture the images but the FITS data needed for Exoplanet Watch. I'd never used this program before, and I learned real quick it's NOTHING like iCap. I wasn't able to figure out the gain, exposure, or other controls and despite being centered on Jupiter it took another 10-15 minutes to get it to come up on the screen. I was able to get a 1 minute video of Jupiter, but it was worse than the picture I took with iCap.

The worst part was when 10pm rolled around, and the neighbor's sprinkler system kicked on, hitting me & my telescope in 40 degree weather. I took it as a sign to call it a night, got all my equipment back inside, and made myself a cup of peppermint hot chocolate.

So last night was a major learning experience with a bunch of takeaways I hope to pass on to everyone out there who're wanting to get into astrophotography or collecting video/still image data from your telescope. If you just skipped to the bottom without reading about my trials & tribulations, here are the short notes:

  • During setup, I need to set up my computer facing north (for better determination of how my scope is slewing in relation to my software), and needs to be an accessible distance from the telescope so aligning and calibrating isn't a pain. To reduce computer glare, Windows 10 and 11 settings have a night mode feature that can be turned on.

  • Practice with all the software before going out! This will prevent wasting time figuring it out on the fly. I can set everything up inside and not only practice, but make changes to settings like auto file naming and file storage.

  • I'm going back to my Army training and writing out SOPs (Standard Operating Procedures) for viewing sessions-hardware setup, alignment & calibration, navigation, and data & image capture. Having written instructions will help since my memory is crap.

  • Prior to viewing sessions, figure out statistics on what I'm going to view. If I'd known prior to setup that I wouldn't be able to see a 10.20 magnitude star with my equipment, I wouldn't have bothered. Planning ahead for both what I want to view and what else I could view will prevent me from flailing around like an idiot.

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