Exoplanet HAT-P-66b (25/2/2022) – IMT3 + Visual with 22″ Dob!

21:24 – 03:00

So for the first time in a while the observatory is back up and running and it’s Friday and it’s clear! So Bob came over and we set about imaging an exoplanet and getting the 22″ Obsession dob out of the warmroom where it had been sitting since November, and moving it down to the observing plateau by the IMT3b observatory.

A few nights back, during the week I had managed to get the 12″ in the dome balanced with my original 2004, 5″ Skywatcher 130 reflector as a guide scope and the Skywatcher Esprit 120 ED on the other side. The 5″ now guides, however the QHY camera on the 120 is not currently connecting so I need to investigate. Also the MEII hand controller is sending erroneous signals to the mount so I needed to disconnect as it kept saying ‘joysticking’ and moving the mount. Unfortunately the 5″ was pointing at the dowel so I used off-axis guiding instead.

Blue 5″ scope pointing at the dome

I selected an exoplanet on the Exoclock website, and set about imaging. Unfortunately due to my profile on exoclock being set to UTC +1 and me not noticing I started 45 mins into the transit! I will now use this as a test run and process the data and submit.

Exoplanet schedule

So first up was moving the 22″ down to the plateau so it could cool down. I had planned on taking it back up to the Warmroom, however it is so heavy I have decided to keep it in the workshop. I will make sure I connect the electric up for the workshop this weekend thus allowing for the new dehumidifier to be switched on and operational.

22″ UC Obsession telescope

Whilst the 22″ cooled down, we went back indoors and setup the 12″ in the observatory to image the transit. The focus point was 25,000 and I made sure I selected the Red filter. I slewed and aligned on the exoplanets host star and then settled on a 5min exposure due to the low brightness. I started imaging at 9:24pm, the transit start was 8:45pm 🙁

HAT-P-66 b

Whilst imaging continued we went outside and set about setting up the 22″. Things I learnt from this first public outing were;

  1. Remember to put the shroud on
  2. Remember to pub the secondary shield on
  3. Remember to collimate the secondary first
  4. Remember to fit the Telrad dew heater
  5. Remember to find a 40mm eyepiece
  6. Remember to download and print the Parracor chart
  7. Remember to set the Parracor to the correct setting
  8. Remember to buy a 12v battery powered hair dryer
  9. Remember to buy a secondary dew heater

We collimated the scope and then went on to look at M42 which with the 24mm Panoptic looked great. We then slewed to M45 the Pleiades but of course the open cluster is too wide for the for I was using. Then we tried find M81 and M82 but I found this difficult due to the lack of bright stars in the area. So instead we went to the Trio in Leo.

M65 and M66 looked fairly bright and you could make out the dark dust lane in M65. NGC 3628 was visible with direct vision, however with adverted vision it was much easier. It appeared very long and thin.

We had to use s hairdryer on the secondary a lot. The Telrad also dewed up as did the eyepiece. The primary mirror was fine, although with direct headtorch light looked like it was dewed, but upon inspection this was not the case.

At midnight it was time to pack up before I had to do a meridian flip. Bob helped my dismantle the 22″ dob and then place inside the workshop. I could not move it into the room without dismantling which was a shame. It is far too tall.

Once done, Bob headed off home for a well deserved rest and to warm up due to it being 0℃. I headed indoors and performed the meridian flip at 0:23am.

I then left the observatory running until 2:30am whilst I wrote this blog, had a glass of wine and ate an easter egg 🙂 I also went back out to the workshop to tidy up the telescope eyepieces etc that I had not put away.

At 3pm I went on to take luminance for M85 that I needed to complement the RGB data I had processed. I let this running and went to bed.

M85 Lum 300s

I took flats and dark flats in the morning, although I had to increase the exposure to get the required level for the flats. This is strange as they should be the same. I am now concerned the camera my be playing up and causing an issue. I will investigate.

Viewing Report – 26th April 2020 – IMT3

21:30 Slew to M85

Camera -23°C, focus point 74534, temperature 15.81℃

Frame & Focus / Plate Solved / Centred

21:38 Autofocus Run – Failed.

21:50 Integrating M85 Event 1 Frame 1 for 300 seconds
Lost guide Star

22:13 Switch Guider to SW Lodestar

Integrating M85 Event 1 frame 1 for 300 seconds. Aborted run as M85 approaching the meridian and guiding graph was not looking good. Guider not calibrated.

Meridian flip to Chertan in Leo, Tak FS-102 now on top of configuration, Esprit below the OS 12″ so will be the better to guide with the QHY5 MiniGuideScope attached to the FS-102.

22:51 Slewed to a star field near Chertan for Auto Focus run. Start focuser position 72885, final focuser position 72178 ….. nice graph.

22:56 Calibrated QHY5 MiniGuideScope guider

Review calibration

23:08 Calibration suceeded, guiding.

Stoped guider and slewed to M85 which had just crossed the meridian.

Frame & Focus / Plate Solved / Centred

23:21 Integrating M85 Event 1 Frame 1

23:44 Telescope connection lost due to poor communication

23:48 SGPro reported USB error – lost FLI Focuser. FLI connects Ok in The Sky X.

Fix is to click on the spanner in SGPro for the Focuser and Rescan, Focuser now reconnects.

00:01 Re-centered M85

PHD2 restarted as it appeared to have hung.

00:12 Integration new Luminance sequence Event 1: 180s, Event 2: 300 seconds.

Viewing Report 20th April 2020 – IMT3

Viewing time period – 20:15 – 23:46


H56-1 / NGC2903-OS-Ha-300s x 12 – Done

NGC3395-OS-Ha-300s x 24 – no Ha so aborted

M94-OS-Ha-300s x 8 – Done

M85-OS-Ha-300s x 24 – no Ha so ignoring

Flats () Darks () FlatDarks ()

Camera Temp -26℃


  1. Cool down scope and dome – done
  2. Turn off Dehumidifier – done
  3. Turn off fans on scope – done
  4. Find home – done
  5. Slew to nearby star to target – done
  6. Select filter and focus – done 74,517 Ha – done
  7. Slew to target and take a test image using Frame and Focus – done
  8. Solve and Sync and then right mouse click on object and Slew Here – done
  9. Setup SGPro Sequence with details – done
  10. Make sure guider connected and calibrate – done
  11. When guiding run sequence – done

Tonight we will take a bunch of Ha images for 4 targets we have been imaging recently with Ha data being provided through the 12″. I have selected the 4 objects in order of passing across the Meridian first. We should aim to get 2hrs of Ha in each, in which case we may need to take the rest tomorrow.

Auto focus run before dark on Ha using 20s subs @ 21:00 focus position is now 74,517 at focuser temp 15.84℃

Autofocus on Ha

Autoguiding on 10s with one of the 2 stars in the FoV of the guider for OS12.

@21:17 started taking the first image. Noticed quickly the guiding in Dec went up, so stopped and recalibrated guider. Then started guiding on 8 second subs.

Guiding 8s OS12 Lodestar

So the sequence is now running and taking frames of the first target in Ha NGC2903 aka H56-1.

H56-1 / NGC2903 Ha 300s

After 12 x 300 seconds on NGC2903 I slewed to NGC3395 and took the first Ha image, but unfortunately it was very dim so not worth pursuing. Instead I have now switched to M94 which is currently on the East side of the Meridian. I will take 24 x 300 seconds Ha with no guiding. It will require a meridian flip in about 90 minutes. I will then leave Bob to complete the Ha on M94 for the rest of the night as M85 does not have any Ha within it.

Bob continued and had a little success, cloud rolled in at 23:46 so frame 9 onwards are no good so we got 8 frames in total for M94, we will continue another night. The shutter was closed as Bob did the meridian flip due to cloud.

I tried to take calibration frames the following day at 7pm when the outside temp was 15.5℃, the inside was 18.5℃ but the ASI camera on the OS12 would not get lower than -25℃. I now concur for with Bob and GingerGeek that we should lower the cooling temp to -20℃ for the remainder of the Spring and Summer returning to closer to -30℃ in the Autumn / Winter. For now I had to wait for the temperature to drop outside and thus inside to cool down the final 1℃ to take the calibration frames. By 20:22 the temp outside had dropped to 12℃ and the internal temp to 15.8℃ which was enough to cool the camera to -26℃.