After Starfest…
I got back from Starfest on Sunday. It was a very enjoyable session though I only imaged for one of the three nights. On Thursday night we had a considerable cloudburst which took up most of the night, so most people turned in early, and on Saturday night I spent time walking around with friends looking at and through some of the Monster scopes (25”!), but on Friday night the sky was clear and dark (about 21.4 magnitude/sq.arcsec, though I didn’t record it and may be off a little), so I spent several hours puttering about with the scope and camera. I aligned the scope very roughly by levelling the mount and synching on the sun, then adjusting the mount position to minimise the telescope shadow. This worked well enough for visual observing, and surprisingly well for imaging. I had neglected to prepare my computer adequately for shielding others from the display, so I worked the imaging from my camera’s LCD screen. That led to a few oohs and ahs as I reviewed the captured images in the camera, but reviewing them on the computer screen later was disappointing.
The image shown here is a composite of two 30-second images of M8, the Lagoon Nebula (lower) and M20, the Triffid Nebula. Processing consisted of level adjustment and the removal of a dark frame. There is no stacking to reduce noise as I only captured one image of M20, but I will process M8 again as I think I have a couple of decent images of this object.
I also tried five minute captures, but at that point the lack of alignment (sounds familiar!) shows up objectionably. I suspect the alignment was out because I left the scope unattended briefly while putting the computer away, and there were a couple of folks hanging around when I got back. The images still looked ok on the camera LCD, so I kept going. Next time I’ll be sure to have some sort of red screen for the laptop. The images do show that five minutes was a reasonable exposure, and that longer exposures could be attempted with autoguiding in place or at least a guide scope so that the scope could be guided manually.
Speaking of guiding, I have picked up a ToUCam and an Orion 80mm f/6 which I hope to set up to control the scope. More info on this as things develop.