I’ve waited a long time to get a good night for shooting. What was not expected : a lot of people at my usual quiet spot.

As I mentioned in the previous post, because of some guiding issues, I shifted to Pacman Nebula during my shooting session on Tulip Nebula. The target was bright enough to shoot only 19 lights frames exposed at 180s each.

I know that this nebula has some blue part (O3 gases), but I didn’t want to compromise my polar alignement changing manually the filter. The Hyperstar lens is replacing the secondary mirror of a Schmidt-Cassegrain Fastar tube, so a filterwheel is not an option. There is a filter drawer between the Hyperstar and the camera … and if you are not that sure you can change it without moving the tube, then it’s better to let it go.

I got guiding issues on this target too, and I need to understand what went bad. On my next session (an upcoming posst), I got the same thing and I think it is about the automatic guide star in PHD2 (the guiding software) being too low. I need to work on it …

• Exifs : Celestron C9 + Hyperstar / PegasusAstro Nyx-101 / PlayerOne Poseidon C Pro cooled at -10°C / Askar D1 HaOIII filter / Guiding System Askar 135mm scope with PlayerOne Ceres C

19 lights 180 seconds each - 16 selected for stacking (48min exposure for final shot)

20 biases - 20 darks (done at home in a dark room the day after, these are difficult to do on the Hyperstar) - No flats.

Stacked with Pixinsight (WBPP)- Post-Treatment with Pixinsight with a minimum of processes.