Details

• Rig: ASI 1600MM Pro + Sky-Watcher 200 PDS
• Software: NINA/PixInsight - Software Set 2
• Filters: ZWO 1.25" - Narrowband set 1

    Integration time:
    * SII 75 x 300s (375m)
    * Ha 86 x 300s (430m)
    * OIII 53 x 300s (265m)
    * Total: 1070m/17h50m

    Integration time target
    * Target: 20 hours
    * Progress: 89%

Notes

28th April 2023 I recently acquired a more capable processing PC which has opened the door to re-processing of lots of old data which was languishing untouched due to the unreasonable length of time required for the old PC to run Pixinsight. Nine months after the initial acquisition, the Hubble palette image above is the first of these reworkings. The data is not perfect, O2 in particular being very weak, but the new PC is eye-opening in its capability and speed.

13th August 2022 I persevered last night with various PHD2 settings which seemed to sometimes improve guiding but in every case degenerated within a few minutes into guiding RMS showing occasional huge spikes. Again I threw away half of the subs though some were lost to cloud later in the evening.

   Integration time:
    * SII 10 x 300s (50m)
    * Ha 16 x 300s (80m)

12th August 2022 More lost frames tonight - half of the subs were discarded due to poor star shapes again. I now need to stop imaging and troubleshoot the poor guiding.

   Integration time:
    * SII 20 x 300s (100m)
    * Ha 16 x 300s (80m)

11th August 2022 More lost frames tonight - half of the subs were discarded due to poor star shapes. I spent the first hour re-running polar alignment and running a Guiding Assistant and expected better results. I think there may be a problem with the mount. To be investigated.

   Integration time:
    * SII 10 x 300s (50m)
    * Ha 13 x 300s (65m)
    * OIII 11 x 300s (55m)

10th August 2022 A very disappointing session where over two thirds of the subs were discarded due to poor star shapes. Was the wind sufficiently strong to cause this? I will check the focus of the guide scope but there are few reasosn why guiding perfromance should vary so dramatically between nights in an observatory environment.

   Integration time:
    * SII 3 x 300s (15m)
    * OIII 16 x 300s (80m)

10th August Continuing with the Cave Nebula this evening. I have removed the dew shield which I think catches the wind to see if that imporves the guiding compared to the awful performance last night. Checked the guide scope focus which is giving an HFR of 1.8 so as good as it gets! Adding an equal amount of all three wavelengths.

9th August 2022 I have decided to add as much OII and SII data to this target as possible to provide a better balannce with the strong Ha signal. Tonight is clear but a little breezy.

17th July 2022 Ran a quick test in PixInsight to see what the Cave Nebula data looked like. OIII and SII are quite weak but the HA data is lovely. The total integration time is a couple of hours less than expected at 8h15m.

13th July 2022 Still managing to gather a few more subs each clear night but throw away 10-20% due to poor sharpness (guiding or bad transparency?) I now have just over 10 hours of usable data on this target.

5th July 2022 Guiding went horribly badly last night until, on checking at 12.30am, I ran a PHD2 Guide assistant which showed a huge amount of declination backlash. Once this was compensated the guiding performed well but still with some largish correction pulses on both axes. Not wanting to upset the session and needing sleep I left it running but I now need to check polar alignment and balance before the next inaging session. There appear to be no cable snags.

3rd July 2022 The unexpectedly frequent clear skies have allowed me to try out some new targets, however with some guiding challenges. My suspicion is that as the set up has not been changed in the observatory that the atmospheric conditions are causing the erratic results. It has been very humid with heavy dew for the last few days following a week of substantial rain. Here are three extracts from the PHD2 logs from the same night showing bad (1.13px RMS but the results seem much worse than this - see top image), average (0.45px RMS) and excellent (0.17px RMS) guiding stats. The only difference between the current set up and the really consistent guiding of recent weeks is the target and the seeing.