It was around 30 degrees with a stiff breeze, but I could see Mercury clearly sinking toward the western horizon. One thing I have found is that speed is of the essence when imaging Mercury. The planet is usually low on the horizon when it becomes visible and it sets quickly. I set up, my hands rapidly numbing in the cold (you can't use gloves to set up a scope), and powered up the scope.
I found Mercury, centered it, and replaced the eyepiece with the imager (a modified Lifecam in an eyepiece tube). I had a tough job centering the planet in the field. My ETX has some backlash problems and fine adjustments can be problematic. In addition, I could not precisely polar align (no time and the pole star was not visible), so the planet drifted out of the narrow field of the imager rather quickly. After 3 or 4 minutes, however, I had Mercury centered and roughly stable. I hit the capture button on SmartCap and the program locked up completely. I've never had that happen before, but it locked solid. I had to manually power off the machine and restart it. By the time the laptop came back up, the planet had drifted out of the field and I had to send more time recentering. Focusing was hard with numb fingers and a bouncing scope. The planet was twinkling viciously and the image in the scope was almost formless. For some reason, the adjustment sliders stopped working in SharpCap, so I went ahead and captured a few hundred frames monochrome (SharpCap comes up with the saturation at zero). I restarted SharpCap and then took a couple of sets of color captures. The first showed the pinkish color of the planet well, the second was overexposed, and SharpCap locked up again solidly and I was unable to adjust the image. By this time, Mercury was very low and I decided to hang it up for the evening.
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