Instrument: Celestron SCT
Mount: Orion Atlas EQ-G
Method: Go To
7:00 PM, July 28, 2012. I arrived. We talked DSLRs for a bit. I showed him the special custom feature menus for controlling the mirror lock.Mount: Orion Atlas EQ-G
Method: Go To
We set to work testing computer control.
Downloaded the latest Prolific drivers from the web and installed them. I hooked up my USB-to-serial adapter from The Source. I showed Manuel show to determine the COM port, if necessary, from the Windows Control Panel Device Manager list.
Fired up Stellarium and configured the telescope plug-in. No joy. I wondered if it might be a version issue so I upgraded his Stellarium from version 0.10.x to 0.11.x. While installing, after he assured me there were no custom settings or landscapes, I deleted all the old configuration data. We tried the application again. Still nothing. It would not connect. Jumped on the web and did some searches. It was optimistic. It sounding like some people were using it directly, that we didn't have to using the old control drivers or ASCOM. I finally found a note that talked about various Windows 7 settings and that gave me a clue. Probably a 32 vs 64 bit issue or something with Access Control. I forced the app to run in XP SP3 mode. Success!
We were driving the Orion Atlas EQ-G with Stellarium!
I cautioned Manuel about the lack of control. I emphasised that Stellarium only does slewing. No parking. No alignment options. One cannot cancel a slew... I urged him to be careful. I wondered if Orion had anything like Celestron's NexRemote. Manuel did not have any additional software. I didn't see anything on the Orion web site.
We headed outside for the parkette.
10:25 PM. I completed preliminary testing for Stellarium on the 'scope while Manuel fetched a few more items from the house. It worked. Quickly, I viewed M57, the Tim Horton, Albireo. I let Manuel slew to M13. He liked it.
I set up the ASUS netbook computer put on some music. Some good ole' rock and roll, for Manuel.
We started the polar alignment process. I manually aligned the mount with the little mount 'scope. And then we fired up EQ Align. Having good views of much of the sky, we were looking forward to a good run.
10:59. We were half way through the EQalign process.
11:47. While waiting for 10 minutes for the drift analysis, I did some whole sky viewing. Reviewed my star names. I spotted ΞΆ (zeta) Ursa Minoris. I checked the brightness: mag 4.25. Not bad, despite the moon light.
12:00 AM, July 29, 2012. The aligning software was done. Interesting. We made only very small adjustments to the mount during the process. In some cases, just loosening a knob was all that was needed. I.e. we didn't need to make large changes. I realised that meant that my initial polar alignment with the mount 'scope was rather good. Probably within 3 minutes-of-arc. We did the altitude adjustment 2 times, releasing and retightening the top screw. We did the azimuth once.
We considered the alignment software. It certainly was powerful. And now familiar with the process, it seemed much faster. And fairly straight-forward, despite poor English documentation. A keeper! I encouraged Manuel to ponder a presentation. Of course, he wouldn't be able to show it live; he'd have to simulate it. Perhaps he could take screen snapshots.
I had wondered earlier if Manuel's use of computer control might be limited. I'm biased. I find it invaluable. For my visual work. For star parties. But as an imager, Manuel may not need to drive the 'scope about the celestial sphere. He's on one target for the night... Yet having the Stellarium drive the 'scope during the alignment process was actually very handy. It made it much easier. I hadn't expected that per se.
I wasn't sure his original intention but when he saw the sky and the constellations, Manuel suddenly said he wanted to image the Great Galaxy. I checked SkyTools and found the elevation of the Andromeda Galaxy. Behind the east row of houses. And even then, when it rose, it'd be directly over their roofs. And over the city. In the light dome. Through a lot of air. A bright gibbous Moon... I asked if he didn't want to work on M13 so more. Nope. OK. Well, we have to wait for about 30 minutes then, I said.
12:11 AM. I observed the Cat's Eye nebula, in Draco, for fun. It was very small and very colourful. A blue-green pinpoint.
12:22. M31 had cleared the roof line. In the eyepiece, we spotted M32 below! We couldn't see M110.
We installed the QHY-9 camera. Manuel started to focus. I reminded him that he need to focus first on a bright star.
1:15. Manuel started imaging with the QHY-9. The galaxy was still large, taking up much of the frame. I successfully determined the orientation by comparing with the simulation in SkyTools. I suggested turning the camera to get a better composition, given the aspect ratio. He agreed. I rotated the camera 90 degrees. But then, I wondered if we went too far.
He kept trying to push the subframe times to draw out more detail. But we kept getting non-round stars above 45 seconds. I wasn't surprised. We weren't guiding. I wondered if it was the periodic error showing. He had never done the training. The 20 and 30 second subs were good. Even SkyTools did not recommend longer subs until the Moon set. It showed our signal-to-noise to be 7 (after 2:30, it would double).
We also saw some coma in the corners.
At one point Manuel said, "I think we're gonna get lucky, I don't know why." I thought that very curious. Astroimaging does have a dash of luck. And that applies to weather, seeing, transparency, etc. But the things one can control? Alignment, gear errors, motor errors, cone error, glass distortion, dew, stray light, moonlight, elevation, heat sources... all that can be managed. Very interesting.
2:00. I was certain of it now. The field rotation was not correct. Or best.
Unprocessed 70 second sub. North is up; east is left. M32 is easily spotted below centre, slightly left. M110 is just barely visible near the top-right corner. The bright star below M32 and slightly right is HD 3914 at magnitude 7. Mag 13 and 14 stars visible in the field.
We captured a few more subs. I reminded him to take some darks. And called it a night.
We saw some weird streaks or lines in some of the subs.
I thought it ironic that we were packing up at precisely Moonset.
I was fairly pleased the evening. We tested the USB adapter with Prolific chipset from The Source and found that it worked. We tested Stellarium with the control cable and USB adapter and found that it work. And took advantage of the conveniences immediately. We tested the EQ Align software with a good view of the sky and found it worked very well.
2:35. Back home.
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Wikipedia link: Andromeda Galaxy.
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