This is an old, familiar target for me. There are a few hours in January-March when there is little else visible from my backyard that I can shoot in the eastern sky. This year, I was planning on spending five hours on it to get a deeper image. I was also trying out my re-furbed H9, back from England, and a new Astro-Tech coma corrector. I transferred the FT focuser to the Orion 6" Imaging Newtonian, put the coma corrector on the filter wheel, and set up in the backyard. I started at around 8:40 pm. By 10:25, I was shooting and quickly realized that the distance between the coma corrector and chip was wrong, probably too far. I went out, took the whole assembly apart, removed an extension tube, and put it all back together. This image shows much better control, actually quite good. I have some oddities left, which I cropped out. I'm not sure whether they are from camera or corrector.
Anyway, I had everything focused and trained on NGC 2903 by midnight, and I was prepared to gather light on this distant galaxy for the next five hours. After 40 minutes, I looked outside. Clouds! Ahhh. How did that happen? I checked the weather forecast. It had changed while I was setting up, from clear to cloudy for the rest of the night. Oh, bother. I brought the whole assembly inside.
That is why this image is only 6x5'. That's all I could get. But, you know, I post what I get. It's a blog, not an art gallery. Transparency was about a 5 out of 10, so with reflected light of the burbs, there was a bit of sky glow. But, hey, it's another galaxy, and these details are all available to those who can look up with the right equipment! Distance estimates for NGC 2903 range from 20 to 38 million light years.
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