Don’t think I’ve mentioned it on this blog before, but I’ve been a self-labeled Space Nerd for as long as I can remember. The science and physics are fascinating, but looking at it is absolutely beautiful as well. My folks had given me an entry-level 4″ refractor when I was young (along with some moon and solar filters). The first time I was able to see sunspots and craters on the moon, I was hooked. Something about the vast distances, the sheer amount of stuff out there completely intrigues me to this day!
After a long wait I finally invested into a “lifetime” scope a few years ago. It was Orion’s new XT12G, a monster 12″ Newtonian reflector with GoTo and tracking functionality. It is an excellent light bucket! On good nights here in northern California, making out the shape of the Andromeda galaxy with the naked eye isn’t all that hard to do. I’ve enjoyed it immensely over the past couple years, but I got bit by the astrophotography (AP) bug almost immediately. After learning some of the basic in and outs of AP, I began throwing money into savings for a new astro-imaging rig. Earlier this month the time came to pull the trigger on a purchase, and this is what I ended up with!
Just about all amateur astronomers are using CCD imaging instead of film now. It’s far more forgiving and flexible, but the cost for a good camera is steep. The two schools of thought are using a general purpose DSLR camera attached to the telescope, or a camera specifically designed for taking space pictures. Being I had zero prior astro-imaging experience (or really any photography for that matter), I chose to purchase a camera designed only for taking space pictures to keep things simple.
But there’s more. The next decision is whether to use a monochrome or a color imager, the latter often being called a one-shot color or OSC. There are some advantages in using a monochrome camera (which I can elaborate upon in a later post), though it does crank up the complexity factor a bit. To continue my simplicity efforts I chose an OSC imager.
The camera I ended up with is the Orion Starshoot Pro 2 OSC.
If I knew then what I know now, I probably wouldn’t have bought the XT12G. Don’t get me wrong, it’s a great telescope–but really only for viewing. It’s the mount. Almost all large Newtonian reflectors use a Dobsonian-style mount in which the scope is mounted on turntable for Azimuth slew, and on a vertical mounting fork for Altitude slew. While this keeps the mechanics of the mount very simple (and inexpensive) the mount needs to track in two separate axes to follow the sky. Fine for viewing but not so good for photos. Through the apparent view of the eyepiece or camera the sky will not move smoothly as it zig-zags in right angles and will rotate as the night sky revolves around the telescope.
The alternative is called a German equatorial mount, or GEM for short. Unlike Alt-Az mounts a GEM is polar aligned, and after proper calibration only needs to move on one axis to follow the sky accurately and squarely. The result is an image that stays planted in the optical tube with a high level of precision that Alt-Az mounts cannot muster. Perfect for long-exposure pictures! Being Orion has always taken care of me in the past I chose the Atlas EQ-G.
And holy cow is the Atlas EQ-G a big hunk of metal! The mount weighs over 50 pounds without counterweights! Yowzer. Zero fun factor lugging to a dark sky site, but the weight and fortitude of it keeps things stable during long camera exposures. Also, it has an autoguider port which I utilize for more accurate sky tracking. Orion may not be the most prestigious telescope manufacturer out there, but it’s hard to deny the value quotient of their products. The Atlas is a fine piece of equipment for the money; especially compared to the competition.
The telescope isn’t quite the biggest concern in AP applications, oddly enough. In fact, some really good pictures have been taken with smaller refractors, much like my first telescope. However, since I had the camera and mount up to a certain level, I didn’t want to completely undercut them with a subpar scope. Nor did I want spend a lot of dough (the camera and the mount combined = ouch). Figuring I’d stick with Orion one more time, I chose the 8″ Newtonian Astrograph. It’s specifically tailored for photography, and with extremely fast optics (f/3.9!) getting wide deep space panoramas were on the agenda. Since I was already familiar with Newtonian-style reflector scopes and collimating them it was a natural choice. Having a bit of familiarity in this new realm is a good thing. It’s a pretty good buy, too!
I also picked up a Starshoot Autoguider to use with my finder scope, even though it was out of my budget. The Atlas EQ-G ends up tracking things amazingly well, however having that small bit of insurance that everything is staying planted in the viewfinder exactly where it’s supposed to is quite nice. Especially when you’re spending hours and hours out in the middle of nowhere in the dark only to find out all your pictures are blurry. In that context the extra expense didn’t seem so expensive.
Putting it all together
My brother, Ethan and me went out for first light with the scope a few weekends ago. Unfortunately we had a half-moon to contend with, but turns out it was kind of helpful as we had no idea what we were doing and needed to plenty of adjustments in the dark. I guess it’s an AP rite of passage to photograph the Orion Nebula. Orion is high in the sky throughout Winter and M42 is a very bright object making it easy to capture. Perfect noob material!
We made plenty of mistakes: Not taking a “dark” series of images, forgetting to disable the laptop’s sleep timer and losing about 30 minutes’ worth of exposures (grr!), completely misadjusting the coma corrector lens, having the collimation a bit off (tried to do it in the field without much success), as well as not having a clue how to focus the scope with the camera installed and doing it “by eye” with the camera out.
Nonetheless, I think our first effort is nothing less than extraordinary. I give less credit to the operators and far more credit to the exceptional performance of the equipment: We’re hard evidence even complete dummies can take great photos! Sure there’s some blurriness and obvious visual distortion–but this is plenty of incentive to get me back out there again. What do you think?