Camera rework

The need for a larger camera FOV had become painfully obvious, but I wasn't happy to put out the cash for a bigger camera. The final straw was when I realized that, in order to connect my separations to the Sun's celestial frame, I needed to be able to center Venus on the solar image. I couldn't determine the center of the solar image unless I could have the disk completely on the chip.

After a bit of research, it became plain that it would be smart to remain in the same camera family in order to stay compatible with the hardware and software already in place.

Looking at the other ZWO cameras, I wanted a monochrome chip with a larger physical format. The MM174 seemed to be a good match to my needs. Here are its specs:

At an effective focal length of 0.74 meters or about 29 inches, this camera offered a 0.55 x 0.87 degree FOV, which, compared to my former camera's FOV of 0.28 x 0.37 degrees, had almost 5 times the area. Due to the larger pixel size, 5.68 microns to 3.75 microns, the larger chip had a similar number of pixels, so the displays were almost unchanged. The plate scale would be about 2.6 arcsec/pixel. I ordered it and substituted it for the prior camera:

Between my better understanding of the mount pointing problems, and with this much larger FOV, I was able to dispense with the finder telescope. After some fine tuning, I was able to drop target stars within two arc minutes of the FOV center, reliably.

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