Ad Astra Observatory

I spent some time in the fasteners aisle at McLendon’s Hardware on Saturday morning, looking for longer collimation bolts for Trixie. The mirror cell has nice, easy-to-source hardware (1/4-20 countersunk for the main bolts, 10-24 pan head for the lock bolts). I knew that the reason Veronica’s bolt-lengthening exercise went badly was because I’d failed to upgrade the springs, which are the “push” part of the push-pull action. So I spent some time figuring out springs, too, and was able to find a set that looked reasonable.

In a nod to aesthetics, I decided to put in brass bolts to replace the stainless stuff that had been in there. Trixie’s original build used brass hardware, but at some point I lost interest in all that, and switched over.

The new bolts went in fine (although you have to tear the whole mirror cell down to do the replacement of course), and the new springs work a treat. I spent a little time collimating the scope, and moved on to other projects, waiting for clear sky.

Among these was another attempt to get my astronomy rig running under a VM. I sort of started to make progress there, but for now I’m sticking to the PC. There’s some kind of weirdness between various implementations of USB under VM’s that really makes things difficult.

I have to take a moment to give thanks to the astronomy gods, because it seems like I get a single clear night right when I need it, keeping me going on this journey towards getting my astrophotography rig running again. After several days of rain, Sunday dawned clear and bright, and it stayed mostly clear all the way until the optics frosted up around 11:30pm. If I’d had dew heaters on, I could have gone all night, as it was still clear on Monday morning. Nice!

So as soon as I could see Jupiter, I started setting the scope up. I’d have started earlier, but I continue to worry about dewing optics, so I wait until I have something to look at. When I started setting up, it was still light out, but by the time I got started on polar alignment, I could see Polaris. Perfect. I need to make a fixed spot on the driveway to set the scope up, because I end up having to do a lot of tweaking every time. Shrug. The polar scope has been working well enough for what I’m doing.

I got Trixie mounted up and balanced, and then put the camera into the focuser to confirm that the new collimation bolts had done their job. They had! W00t! With the MPCC attached (and the compression-ring drawtube), I was able to take a star past focus with about 3/8″ of backfocus left. So somewhere in there is “perfect focus”.

The night turned into an exercise to find that perfect focus point.

I’ve had these focusing exercises before, and so I was not confident in the process, but I proceeded anyway, because it seemed like the next logical step (although that may not have been the case, it is however the step that I took).

I pulled the motor focuser from Veronica and installed it on Trixie. Veronica is pretty well in pieces now, as I’m waiting for the new spider to arrive, too.

I then dug out enough cabling to get the motor focuser running. It turns out that I’d acquired a 12v/1A wall wart with a long(!) cord at some point. Nice. I have never really gotten the hang of how to set up the motor focus control box. If I need to use it at the eyepiece, I need really long cables going all over the place (one to the focuser, one to the computer, and one to the power strip), which I then have to deal with for the 95% of the time that I’m not actually using the thing. sigh.

Anyway, I confirmed that the 350D and SSAG were both working in MaxIM DL 5.08 on the venerable Dell XP machine (which was driving the observatory in CA), and quickly got the motor focuser integrated as well. Art walked me through the settings in FocusMax (I am going to have to write that stuff down at some point), and I spent the next couple of hours attempting to complete a “first light wizard”.

In short, that sucked.

I needed to tweak the exposure times so that a decently-bright star would show up every time. I also had to get the focuser back to “somewhat focused” after FocusMax sent it off the deep end a couple times. MaxIM also crashed quite a bit. Once I got everything running, it was starting to get really cold, so I switched from sitting at the scope in the cold to running VNC from the Mac (that worked on the first try! Thank you, previous me, for setting that part up!). The Mac had its normal problems getting Wifi signal out in the shop (I need to figure out how to extend my wireless network out there), but at least it was warm and lit.

After my second or third failed attempt at a V-curve, I got mad, gave up, and pointed at a bright star to focus manually. I got things close enough and moved on to point to some DSO or another to try to get an image out of the evening.

I fear some kind of serious problem in my optical train — bright stars were coming out sort of kidney-shaped and there were double diffraction spikes, even when I was as close to focus as I could get it. I need to do a full analysis, but like I said, at this point, I just wanted to see if I could get an image of something.

I was pretty cold and tired, so when I started noticing that the optics had dewed up, I gave up and shut down for the night. When I pulled the rig apart and got it back inside, I noticed that it wasn’t just dew on the optics — there was a small coating of frost on some parts, too. Yikes.

So in retrospect, I actually got a lot of new stuff done. Trixie can now focus every piece of equipment. I got the full imaging rig up and running (2 cameras and a motor focuser). I tested guiding. I tested DSLR control. I tested motor focuser control. I attempted some GOTO’s. I got VNC running again so I can check things remotely.

On the down side, FocusMax remains a thorn in my side; I think that Art will end up having to massage it himself at some point. I need to figure out the strange images that the optical train is putting out. I’m still searching for a VM solution to the observatory, because the Dell is not going to last forever. And I discovered that I’m really going to need an observatory here in WA, because sitting out on a cold winter night is really not cool, and heaving around Trixie at the start and end of the session means that I am cutting my sessions short, so that I have enough stamina to do teardown at the end of the night.

Good progress, I should be able to get an image (even a really terrible one) next time I’m out.