Tonight I thought I'd go back to the Horsehead and redo the H alpha exposures. But when I asked the GoTo to take me there, it instead put me right on the Flame Nebula. I decided to go with the what the mount apparently preferred.
I'm current imaging with my MK-67, an f/12 Mak-Cass. Its focal length is 1800 mm. The ST-8300M's pixel size of 5.4 microns is about 1/3 the size it should be (about 16 microns for the average poor seeing I get here). I'm therefore binning 3x3 on the camera, which give me about 1.65 arcseconds per pixel. Looking at some of the subs, this seems to work very well.
As I write this I've got 22 subs in for the Flame. Tomorrow night I'll go back (unless the mount has other plans) and shoot some other bands if it holds clear.The odd lines I mentioned last time are gone. I asked on the MAS forum about the noise I was getting the other night. It looks like the best suggestions were about bad or loose cables. Something was acting up tonight when PHD went crazy. The oddest thing was that each exposure caused the PHD window to jump back and forth by about the window frame's width (8 pixels or so). It also couldn't calibrate correctly. Multiple restarts didn't fix this, nor did unplugging the USB cable at the laptop. However unplugging and reseating the cable at the autoguider did the trick. I begin to suspect that the autoguider's socket is the problem.
The Horsehead image came out okay, but needed more exposures. I think the flame will look much better. I aim to get 30x5min exposures for it.I'll post the Ha images in the next couple of days.
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