However, it is SO BRIGHT. I have a perfectly clear night, the forecast is even calling for good seeing and transparency conditions, but I can't image because the moon is up nearly all night, and it's nearly full! And it won't rise late enough to squeeze in any imaging between post-sunset darkness and moonrise until a week from now :( So a week of taking darks it is!
Except, I'm having a bit of a problem with the dark frames. Here is a single dark frame, auto-stretched:
It looks like a bright light, just off the edge of the frame. Now, this is a 10-minute long frame (on my ZWO ASI294MC Pro), so it shines brighter above the background, but it's present in shorter-exposure frames too, just less obvious from an auto-stretch. My first thought was that I had a light leak somewhere, so I made sure I had the cover over the scope the next time I took darks. But the result was the same. I debayered the image so I could see if the light had color, but it was white, which either means it's actually a white light, or it's far enough infrared to not look reddish and just appear white (much like how a remote control looks in your cell phone camera). The extra weird part is that it's not really showing up in the light frames. So then I thought, maybe it's a lot dimmer than it looks, and the light pollution and target are so much brighter than it that it won't show up. However, when I calibrated some light frames with matching dark frames, the light showed up inversely as a shadow, since it had been subtracted out from what wasn't really there in the image. Very weird. Further testing is needed...unfortunately this camera doesn't have a physical shutter, so light could be leaking in from somewhere, but I have no idea where, except for its own red LED that is quite far away and facing the opposite direction as the camera chip. (And I haven't seen this in my ZWO ASI1600MM Pro, which is the same body design). More testing is needed...
Anyway, since the moon was setting around 3:15 AM, I set the telescope to start at 3 AM and just do M33, M77, and the Flaming Star Nebula before sunrise. Worked again, no problems! Now I have 168x3-minute frames on M33, which is 8.7 hours. That is hands-down the most amount of data I've ever collected on a single target on the same imaging rig! So I think I'm going to go ahead and process it during this full-moon break and see how things go. Get excited!
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