Viewing Report 28th/29th June 2019 – IMT3 Observatory

Viewing time period – 22:34 – 03:52

Point Run within TheSkyX

Well it was time again to perform another TPoint run and adjust the polar alignment. Tonight was all about refining the previous alignment using the Point software which then measures the error once you have 20 points and reports back how many ‘tic’ marks on the mount you have to adjust.

The first run produced an error of +17.8 arc minutes for the azimuth so I had to a adjust the mount counterclockwise 22.8 tics. The error in dec was 8.3 arc minutes so I had a smaller adjustment of 8.6 tics on the altitude.

justing the mount using ‘Tics’

I then ran a second Tpoint model, again just over 20 points and this time the error was reduced to 12 arcmins for the azimuth but 12 for the altitude so dec. Instead of adjusting by tics now was the time to start drift aligning using PHD2.

I brought up the program, found a start near the Meridian and near the celestial equator and quickly found a guide star since my FoV indicators within TheSkyX now line up. The error in the drift align matched very well the error within the Point model so I adjusted by the number of Tics suggested in TheSkyX. Once done I performed a third Point model of 20 stars.

Example FoV Indicators

By this time it was already 1:34am and I had been refining this for 3 hours, the new model told me that I was only 4.2 arcseconds out in azimuth and -2.9 arc mins out in dec. Once again I went back to PHD2 and from then on just drift aligned to refine the error.

PHD2 Drift Alignment small error

This took until 3am when the error was a mere 0.8 arc seconds for the altitude so Dec and 0.1 arc seconds for the azimuth so RA. This was then good enough to take a quick 10min unguided image through the 12″ which is 2.5m focal length. Very impressive.

10 min unguided exposure – note the doughnuts due to it getting light

I then quickly finished off by performing another 20 point TPoint run so I had a model to use tomorrow night so that both Bob and GingerGeek can further commission the two refractors. I will perform a further longer Point run for turning on ProTrack in a few months.

For now it is light, the birds are singing and I ought to go to bed 🙂