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3. M31, Andromeda Galaxy
Notes: The detail in the central nebula is good and the core is less overexposed. Our polar alignment was fair at best, as we kept the alignment from October 21. The stars are closer to round than in images (1) and (2), and focus was improved by using the fine focus in Nebulosity. The short exposure times have the advantage of reducing smears caused by tracking error and poor polar alignment, but they also have drawbacks: (1) a poor signal to noise ratio as evidenced by visible red grain if we try to magnify; (2) only a fraction (half?) of the disk is visible because we are not getting enough photons from the outer regions of the disk.
Altered in Photoshop, this image became Image (4), above. Detail in the disk was brought out by selecting the entire disk region, putting it in its own layer, and stretching it. Zoom in/out with ⌘↑(+/-) (Mac), ctrl (+/-) (PC).