I had another clear night last night and managed to get a few hours on two targets. I’d previously tried this target before on my IMX484 based camera and I’d barely caught sight of it. My new camera, however, got some good data. I was able to process this and get something interesting but it could do with another few hours of data to do it justice.
I finally had a clear night to test my new camera and it did not disappoint. This is the best, least noisy image I’ve taken yet. I chose Eastern Veil nebula because I’d taken that before so I could compare it directly to my old camera. I plan to make this the first panel in an 8 panel mosaic to try to get the entire Cygnus loop, if I get enough sky!
Finally in early September, we have some visible sky. However, it wasn’t perfect. There was lots of very high level fine cloud which made seeing pretty poor. In addition, the full moon is rising in the North East which makes my favourite piece of sky out of bounds for now. So, I decided to go back to basics and practice my focus & noise control on a boring star cluster. I’ve never actually taken an image of M13 before, but they’re all pretty much the same. Anyway, given such poor conditions, I’m quite happy with the way it turned out.
After a month of cloud, I finally got some sky time from 11:30pm until 3am. I decided that I’d take a gamble and try something different for this session. I imaged with my UHC filter in tandem with my IR cut filter. The reason I did this is that my UHC filter seems to let through too much IR which ruins the stars, so the IR cut will trim the top end. I noticed that a lot of UHC filters are advertised to be used in combination with an IR cut so I’m not doing anything weird. The idea of the UHC is to cut down on unwanted light pollution and focus on the wavelengths that matter. However, this means that light will fall on the red and green photocells in the camera sensor and the blue will be discarded. In effect I’m throwing away a quarter of my data which means my imaging session needs to be even longer. Hopefully this is offset by the quality of data that it actually collects.
If that experiment were not enough, I also decided that I wanted to image more of the sky than I could actually see with my camera. The only way to do this with my equipment is to do a mosaic of more than one image. I decided to start simple and take a 2 frame mosaic. So now my image time requirements have doubled again at a time when I’m not getting much sky.
Over the 3 hour session, I managed to get an hour of data on each mosaic frame however I discovered in post processing that seeing wasn’t as good as I thought it was so I had to discard a number of subs. In total, I got somewhere between 40 and 50mins on each frame.
The end result was a mixed bag. On one hand I’m pleased that I managed to suss out mosaic processing on the first attempt. On the other hand I’m upset that I couldn’t get more data. I’m still on the fence regarding this UHC filter. I’m not convinced that it’s giving me better results than just broadband. Perhaps I need a better filter? The final image is noisy and I stretched it as far as I dared. I then saturated it to death to get something interesting. What a frustrating hobby this is.
Well, it’s wired up and programmed, and it worked first time. I had a chance this evening to test it in NINA. Works perfectly :)
