Well apparently, it’s been over a year since I posted about astrophotography, so I’m well over due to put something up. My last post I talked about setting up an old laptop with Linux to use to control my camera. Like most of what I’ve posted about here, what was a good idea in theory turned out to be not so great in practice.
Without going into all the gory details, the camera control software I found didn’t work quite the way I needed it to. Further research turned up a couple of Windows apps that were designed to do the exact job I wanted to do. One reinstall of Windows later, I had trial versions of Backyard EOS and Astro Photography Tool (APT) installed, and ready to test.
Both apps seemed to do a good job, but the trial version of Backyard EOS expired before I got a chance to test it at night. That left APT for me to use, and it seemed to do everything I needed it to. I did a couple of test runs, and found that while the software worked perfectly, my ability to capture images was hugely limited by not having some sort of tracking mount for the camera.
A quick word on why a tracking mount is essential for most astrophotography: As the earth spins, the stars we see at night will move across the sky, meaning that if we point the camera at the sky and leave the shutter open long enough, the resulting image will show stars as a series of arcs, rather than points of light.
The length of time it takes for this to become obvious depends on the focal length of the lens. Wide angle lenses allow for longer exposures than telephoto lenses. There are various methods to calculate the maximum exposure time before stars leave obvious trails in an image, the simplest being the 500 rule. This method simply calculates the maximum exposure time by dividing 500 by the lens focal length. For example, a 300mm lens has a maximum exposure of 500/300, or 1.6 seconds. My 15mm lens has a better exposure time of about 30 seconds, meaning I was limited to mostly wide-angle shots if I wanted to get decent images.
So, getting back to taking actual photographs, I haven’t been much inclined to do any astro photography, since my results were always disappointing, due to the short exposure times I needed to use. That changed recently, when I acquired a Skywatcher Star Adventurer 2i tracking mount for my camera. My first quick test of the mount, without computer controlling the camera, showed promise. My second attempt is now the header image for this site. I’m looking forward to getting better acquainted with how my computer setup works, and how the tracking mount works. If only the weather would play nice and keep the clouds away at night.
I like messing with stuff and seeing what I can make it do. Computers, electronics, photography are my main hobbies, but I also enjoy bike riding, gel blasting and music.