Thursday, March 19, 2015

Astrophotography

As I said previously, I've been getting into photography, and specifically Astrophotography. I picked up a nice camera, and have been filling up memory card (got a new one on order, as well as another hard drive) with short exposures until I finish building my equatorial mount.

The trick with astrophotos is that since the earth is rotating, the sky is moving with respect to an surface bound observer. This wouldn't be so bad, except that in order to get really great images of the sky, you have to measure (read, expose the camera sensor) for a long time. Long exposures do two things: allow very dim light to impact the sensor, and average out the black background that is space. It's a real battle with signal to noise ratio, and has been a great refresher of my electrical engineering, and even useful for my mechanical engineering background.


This is the best photo I've done so far. It's a stack (read: average) of about 100 four second exposures of the region around Cassiopeia. There has also been a bit of what is called stretching in photoshop in order to bring out the brightness in some areas, and enhance the darkness in others. I've gotten a lot of compliments on it, but I know I can do some way cooler stuff if I just put some work to it. So using my 3D printer, I am making a Barn Door Tracker to help take longer exposures. I'll post some of the cooler stuff here when I get it!