With a near on full Moon, the choices for deep sky were limited so I set about looking for Sharpless emission nebula. First on my list was SH2 136 in Cepheus. I slewed, aligned, selected the Ha filter, rotated the camera to find a guide star, tried to run autofocus which failed (I set the focus point to 18500 for Ha manually) and then imaged a few subs at 600s, which is when I realised the problem.
Nothing but stars….. I googled around and it transpires that some fo the Sharpless catalogue is emission and the rest is reflection! Now I know this useful fact I will double check each image I go after.
Before I moved on I took a single 300s luminance frame just to see if I could see anything at all. The answer was not a lot, so I moved on. This time I choose an emission nebula, much larger than my FoV but still it should be a pleasing object, SH2 132, an emission nebula also in Cepheus.
I set about imaging 14 x 600s in Ha and then went to bed at 23:48 leaving the system running for another 2 hours before hitting the meridian, as I have not setup the scope to flip yet.
It’s been a while again due to work and the weather. A quick look around the sky this evening and make sure I still know how too use the telescope. So after getting focus
I slewed to Saturn as it was up and as expected it was very small.
I then slewed to the Pacman nebula, NGC 284 also known as Sharpless SH2-128. I switched to narrow band and the Ha filter. I plate solved, centred
and then proceeded to take 300s shots.
The camera was called to -15℃, the outside temp was 16.2℃. The focus position was at 18,000. The camera itself was set to Gain 139 and Offset 10, the rotator at 345.560°.
I took 75 x 300s images until I closed the dome, by which time it was very light. I went to bed in-between the start and end of the imaging run, but then realised the dome safety does not work due to the cable from the ASC being severed due to a Stanley blade incident with weed matting.
The good thing is GingerGeek and I managed to focus the ASC during the day on some trees in the forest across the valley and we managed to get it in focus.
I will process the data last some point and see what it looks like.