Now this is an odd one. I just got a request to purchase an image of Arcturus that someone had seen on the New Forest Observatory website. Looking at the image it looked better than more recent 2-framers I’d done of the region. So I went back to the original 2013 data and found the image you see here. This is 60 x 200 seconds using the 3 x Sky90s and 3 x M26C OSC CCDs. And to top it all, it is a single framer. Now I have absolutely no idea how I did this because having a very bright star in the centre of the frame throws out the star tracking prog, it only wants to track on the bright star and a huge bright star is no good for accurate tracking. This is why all subsequent Arcturus images have been 2-framers so I can put Arcturus at the very top and very bottom of the 2-frames and thus track on a much dimmer star. Such are the mysteries of astro-imaging.
