Hearing the experts speak
Last night, I made a special trip out to the wild west of Johannesburg to attend a meeting of the West Rand Astronomy Club. They were having a talk on astrophotography, which was to be given by my new friends Cory Schmitz and Tanja Sund. A quick look at my own efforts, compared to what they’re doing, shows that I have a great deal to learn. I was surprised, though, that they did not have a lot to say which I had not heard at other talks in previous years. In fact they glossed over a lot of the technicalities which I’ve long since memorized and instead spoke at length on what they’ve learned through hard trial and error.
So what did I gain from the talk? First, and most importantly (and something my last imaging session taught me), the mount is more important than anything else. It has to be rock steady, and the polar alignment has to be as close to perfect as you can manage. Second, use tethering software to control the camera and save images direct to hard disk. This will reduce heating inside the camera body, make it much easier to see where the camera is pointed, and allow for exposures longer than 30 seconds. And finally, I’ve had my ISO values set all wrong: Cory is uncomfortable using an ISO of higher than 800 in all but the darkest and coldest of conditions (although with their new cooled CCD camera, which runs at -20°C, that’s one thing they no longer have to worry about). So, my next observing session I’ll spend the required time to get the mount properly aligned. And I’ll put the camera on the piggyback mount, with the 55mm lens, so as to minimize the effect of any alignment errors. And then I’ll see what comes out. And if accuweather’s forecast is right, and if time permits, that will all happen tonight. Here’s hoping!