A few months ago I picked up a Celeston NextStar SLT mount. Slowly, I have decoded the serial commands for the two PIC uControllers that run the altitude and azimuth motors. The uC’s control the two DC motors that drive a worm and large gear to rotate the axis which then through an optical encoder gives feedback on the current location for precise motion control.
Originally I was going to build a full tilt/pan system with steppers, however this system is robust enough and much cheaper. The plan now is to write some python to pull down Astrometry data to align the scope using a raspberry pi and a teensy to do the decoding and joystick control. My longest lens is a 200mm so I think I can keep the full astrometry catalog at that scale on a sd card on the pi to do lookups. I think most of my shots will still be with very wide lenses so I can get away with quick astrometry lookups. So far I have decoded the packet system, but I am failing at grabbing all of the telescope responses due to an issue with CTS/RTS flow control, I think.
Nathan was over yesterday so while I was drinking some tea I thought I would capture the above time lapse of robotlandia. I set my camera to take a picture every 7 seconds, 5 waiting for the system to damp down, and 2 seconds of motion. During the 2 seconds 15% of the time was moving both axes, and then the other 85% I moved the azimuth only. This made for a larger pan and only a small vertical motion.
The camera is not directly aligned to the rotational axes of the alt/az which may cause an issue when doing work on the sky, however for now it adds nice dynamic motion through the scene. I will be adjusting my current mount to one with a quick release and possibly a ball head which will make setup easier.
# Resize the images (wrapper around sips that I wrote a while ago) # gifsicle now has the ability as you can see to do this as you can see # below. shrink -r 750 -o small * # convert to gif sips -s format gif ./small/*.JPG --out small # Combine into a single gif gifsicle --resize-height=500 --delay=4 --loop ./small/*.gif >> rotate_small.gif
From here it is off to gfycat to reticulate the splines into HTML5 video.
Here are some others: