Viewing Report 31st May 2021 – IMT3b

19:25 – 03:28

Bob came over again tonight which is great company. He setup his Skywatcher AZ-GTI portable mount with his Tak FS60 on it so we could do visual throughout the night on a goto mount along with my star hoping through the 100mm binos.

Skywatcher AZ-GTI

I started the evening whilst light, measuring for the replacement T2 (M42) adapter for the camera train. Given the 0.083 microns per movement of the FLI Atlas focuser I need to reduce the image train length by 3mm. So the new adapter needs to be 31mm, current M42 adapter is 35mm. Meanwhile my AstroCat Fluffy decided to get some more sleep before dark.

Fluffy taking a hard earned nap

Next up was writing the Lat Long on the dome so I can give it to anyone that visits. With that done I started testing the rotation of the dome to make sure the dome no longer slips since I put the anti-slip tape around the edge. After spending some 15mins rotating the dome it seemed ok, it would be fully tested later when I redo the Tpoint model. This is due to the 2.1 arc minutes of error in my azimuth polar alignment that needs adjusting by 4.2 tics.

I adjusted the mount as above and ran a 20 point model. This told me the error int he azimuth was less than 1 arc min and that there was no need to adjust the mount any further, however it had low confidence. So now I will run a full 212 Tpoint model to see what it reports.

212 TPoint Model map

On starting the run I hit another problem, the mount hung and beeped. This was due to a balance problem on the tube which is weird as I thought it was fine. However maybe I had not rebalanced since adding the rotator properly. I removed a little weight at the front of the OTA and shifted it backward. I then tried again but again it hung and beeped. It transpired to be the same loose cale I had before, the focuser cable which had come loose. I applied some more white electrical tape to hold it in until I get round to changing the 2.1mm adapter.

At 23:40 I started a new TPoint run and am now 7 stars in and all is well. That did not last for long, around 47 Tpoints and I kept getting blank images. It seems the dome had lost its position. The Home sensor does not seem to be registering. I slewed the dome manually to Home at 123 degrees and synced that back into the dome controller. Starting the TPoint again resumed stars being seen.

Meanwhile Bob was moving from object to object without the AZ-GTI mount. M5, M57, M10, M12 along the way. We easily split Albeiro although Bob was slightly worried about my eyesight as I initially struggled. We saw the head of Scorpius pop up above the tree line but we didn’t get M4 from the IMT Plateau and Antares only just made it above the tree line. So I decided to relocate my bins to another spot in the garden by the Sun Plateau so we got M4 through them. M17 was seen through he 100mm binos also, looking remarkably like a Swan! Finally as it got light just after 3am we nabbed Saturn, Jupiter and the Moon.

We could see the star HD 200329 and Titan along with Saturn

By the end of the night I was at 187 TPoints so not enough for me to be confident the whole sky was mapped, nor enough to fix the model and have Protrack running. I will continue the mapping when dark tomorrow night.