Yesterday, December 28, my planetarium software warned me of an Io shadow transit later in the evening- when one of Jupiter's moons casts a shadow on the planet's surface. The sky was clear and it wasn't too cold so I planned on trying to capture it.
I was worried about the approaching haze in the west leading up to that time. Indeed, it was thick when I got everything set up yet I could almost see the tiniest black speck on the planetary disk in spite of it. The haze actually cleared after a few minutes and I was certain I could see the shadow at x125 magnification along one of the cloud belts. I realize trying to boost the magnification when dealing with planets is not the recommended school of thought, but it worked so whatever!
After I was satisfied I found it and admired it a bit I proceeded to set up my imager. This is where it all fell apart. I have the Orion Starshoot Color Imager IV and it just uses a generic webcam capture software. Having fiddled with the exposure settings and allocating file space I started the capture. I was recording at 30fps for 100 seconds which should have given me 3000 individual frames I'd sort and stack later. Unfortunately, I must not have allocated enough file space and the frame counter at the bottom of the application window was dropping more frames than it was capturing. So I tried again, allocating much more space but as I was recentering the planet and readjusting the focus, the image on my monitor started blinking and blacking out all together. This happened a few months ago with Venus but the imager still picks up light when I point it at the monitor. I'm completely baffled. I decided to try to capture it anyway but I was losing as many frames as last time and it was starting to black out for several seconds at a time so I aborted and got around 800 frames.
Well, ok, let's work with what we have. The first .avi file wouldn't load in Registax. I'm not sure what the problem is but when the progress bar pauses at 67% I know I'm boned! The second file, the one with the black outs, loaded nicely though. I aligned and stacked several times with different quality cut off settings giving me between 200 and 400 frames with no noticable difference so I stacked as much as I could and tried to sharpen the result. That is is what you see below.
I can't be certain, but I want to say I can see a black smudge on the southern cloud band but this may just be wishful thinking.
