Details
- Rig: ZWO ASI294MC + Stellalyra Classical Cassegrain + HEQ5 Pro
- Software: NINA/PixInsight, GIMP
- Filters: None
Integration time:
* OSC 33 X 120s (66m)
* Total: 1h06m
This evening was unexpectedly clear though with a thin layer of high, semi-tramsparent cloud which affected guiding and visibility. Around half the gathered frames were discarded. The clouds got thicker around 1 am so I closed the observatory roof and left the calibration frames for the morning. As has been the case recently, calibration frames have been very problematic but I did finally resolve two outstanding issues:
- The ASI294MC must have the offset set rather than left to default. Confusingly, the ASCOM driver does not allow the offset to be specified in NINA so the native ZWO driver must be used.
- Flats made with the Gerd Neumann flat panel show strange reflections in the Stellalyra CC (and I think the 200 PDS too) when the panel is in contact with the rim of the OTA. When the panel is located six inches away the reflections disappear. This strange problem only seems to have become apparent recently, possibly with the change of cameras to the 294MC and the QHY 268C. To be investigated with the 268C/200 PDS.
As the Moon was below the horizon for the duration of the session I left the rig without filters. This also helped to maximise light transmission - the F12 scope is a little slow for DSOs. However it did perform really well and much better than I really expected it to.
The image above was created using the output from StarXterminator which allowed me to leave behind the background “noise” of the super-bright stars of the centre of the cluster and show better the hot blue and colder yellow stars.
