Ad Astra Observatory

This was one of Those Nights. Everything went wrong.

It started with killing power supplies. I am trying to get a reading of the amperage coming out of the mount, which will hopefully tell me if my worm gear is properly adjusted. But every time I hook up the Fluke to the power supply, the power supply shuts off. After much head scratching and testing, it turns out that I have something wrong with my Fluke. I’ll get it serviced (or a new one). So I can’t check the amperage on the mount.

On the other hand, the mount’s Voltage looks fine. It only drops 0.02 volt between idling at sidereal and full-on slew in both axes. Nifty. I don’t know if that’s a testament to the mount or to the power supply, though.

What was really going on is that I have a brand new scope that I’m trying to get in service. I’ve had the C9.25 for a few weeks now, but I’ve only just gotten all the extra parts that are needed to integrate it into my setup (in particular, I needed a top rail for the guidescope and I also needed a gear for the motor focuser).

So, once I gave up on checking the mount amperage, I had to focus the camera on the new scope. That took forever (RoboFocus is not fast without software, and I hadn’t hooked up the computer yet). I’m used to being able to just push the drawtube to get it close, but I can’t with the C9.25 — it’s an SCT, and the focuser doesn’t have a drawtube.

Then I had to get the finder lined up, also took longer than I was expecting.

Once the main scope was all ready to roll, I (prematurely, as it turned out) started getting set up to image.

I pointed over to M51. It’s a nice easy target, “let’s see what this 2350mm can do” I said.

So I start looking for a guide star and can’t tell if the guider is focused, so I have to go refocus that (which involves leaving M51 and pointing to a bright star and doing that whole mess, which I should have done before I slewed to M51 in the first place…), and get the guidescope and its finder all synched up, too.

OK, back to M51, again. The GOTOs are not dead-on at the moment (higher magnification, plus I’ve been messing with the mount and probably have a shaky pointing model — another thing for the todo list). So I spend a little time recentering; have to figure out which buttons move the object in which directions (it’s upside-down and backwards from the Newtonian).

Once I get M51 centered in the main scope, I point the guidescope to a guidestar and try to calibrate.

But the stupid mount won’t calibrate! I tried everything I could think of (throw it into Visual mode, aggro = 10, etc) and I finally give up and decide that the guidestar is too bright. So go find a dimmer guidestar (have I mentioned how bad my skies are? I can barely see mag 3 stars in the finder). Once I did that, everything is fine, the mount calibrated.

OK, deep breath. Last couple of things and I can start imaging.

So I go to turn off the Visual mode…

AND PRESS DEC- BY MISTAKE. GRRRRRRR!

So now I have to recenter the object (a few 10sec shots on the main cam) and reclibrate the guider. I get that all done, I start up the guiding, and for some reason it’s just hating guiding in Dec. I don’t know what is up. Dec errors are in the 15” range (normally I expect <2”) and steady.

So I try turning off Dec guiding; if the mount is properly polar-aligned, all Dec errors should be related to seeing, and since seeing is random, they should average themselves out.

WRONG. I got a huge Dec drift when I turned it off. Ouch. We’re back to polar alignment problems again (a problem that has been plaguing me for over a year now). Sigh. So, Dec back on, bump up the aggressiveness a bit to keep it in line, and we’re off and imaging.

I have the laptop in the observatory on a docking station so that I can use it with a screen if I have to, but during an imaging run, I keep it closed and use VNC to see what’s going on.

I have a new Mac (long story) and haven’t tried using Mac VNC to connect to the PC yet, so I try it…
Totally screws things up. Screwed it up so bad I had to shut down VNC Server and restart it on the PC. Even after that, I still can’t connect from the mac. I gave up and connected from an Ubuntu laptop.

At this point, it’s 10:30 and I’ve wasted basically the whole evening sorting out bugs.

And even after all that, for the first 15 minutes or so, the guider was still settling in , so the first 3 or so photos were unusable because of trailed stars (a result of guiding errors).

And then everything started guiding fine for the last 8 shots or so, which is nice. I would have shot for longer, but it was well past midnight at this point, so I shut down for the night.

Essentially, I was just doing autoguider/periodic error testing last night, so I wasn’t really expecting a great result.
However, the output photo is just tragic; M51 is escaping out of one edge of the frame, because between recentering and the initial guiding errors, the scope had drifted a *long* way.

What a night. Hopefully I’ve gotten most of the bugs out of the new setup and I’ll be able to just go out and image this weekend.