re: Amateur photo of the Andromeda Galaxy

This is a comment from the guy who took the “picture”

there are a lot of variables to acquiring good data through a telescope. the telescope is attached to a camera, filter wheel and focuser all of which sits on a finely geared equatorial mount, necessary to track the stars within a high degree of precision over the course of many long exposures. the mount is also connected to a second smaller telescope and camera which actually tracks a target star and via a computer program sends commands to the mount to keep the star in the crosshairs. Two other programs run concurrently while imaging: a mount control interface and a sequencer which runs the imaging session: what target, how long, what gain setting, what filter, when to focus, how much to heat the dew heater to keep condensation off lenses. All these systems have to talk to each other for a session to run smoothly, and each of them has their own set of variables. On the rare clear, dark (no moon) night, everything has to run perfectly to get quality data, and acquisition is only part of creating an image. You also need to shoot calibration frames to compensate for optical aberration, noise from the camera and environment, etc. Once you have all the data you need, the second part, processing, has as least as many variables, as you’ve got to take all those 1s and 0s and transform them into a pleasing image. At any step of this process things can go wrong. Hope this helps!


Literally not a real photo
Computer rendition.