My Account

New to Astromart?

Register an account...

Need Help?

Orion’s LaserMate™ Deluxe Laser Collimator

Posted by Clayton Cramer   07/07/2004 00:00:AM

Orion’s LaserMate™ Deluxe Laser Collimator
Test: Orion’s LaserMate™ Deluxe Laser Collimator

My homebuilt 8” f/7 has—at times—given me startlingly crisp and beautiful views of the Moon and planets. At other times, the results have been very disappointing. I would occasionally see Cassini’s Division in Saturn’s rings—but only occasionally, and I knew that the problem wasn’t seeing conditions.

I knew that my experience was pretty typical: a well-collimated reflector is a joy; a poorly collimated reflector makes you contemplate buying an apochromatic refractor. To correct this difficulty, I bought my first laser collimator three years ago from MoonLite Telescope Accessories. (It was a competent, reasonably priced unit that, unfortunately, they no longer make.) The results were impressive. I was now able to consistently get the most out of my optics. When the atmosphere was calm, I could often see Cassini’s Division all the way around the planet, and even in less than perfect seeing, I could at least get a hint of it at the ansae (those parts of the rings to the extreme left and right of the planet).

A laser collimator is the way to go, no question, but there is one problem with using a traditional laser collimator on a Newtonian reflector—-you need to look into the scope from the front, to see if the return beam and outgoing beam are coincident. Since my arms aren’t six feet long, I had to look at the inside of the tube, move to the back of the scope, turn the adjustment screws on the mirror cell, and then back to the front again.

If I could persuade my son to help me, collimation took about 20 seconds. If I did it by myself, it took about ten minutes—-and I would often settle for less than perfect collimation. It was slow, and more than a little frustrating.

A few months back, a friend brought to my attention Orion’s LaserMate™ Deluxe Laser Collimator. The Deluxe model provides an interesting feature: you can do all the collimation from the mirror cell end of the telescope.

The first attempt at ordering one was unsuccessful; Orion was apparently not quite ready to ship. The second try produced one with the speed that I expect from Orion; in less than a week, UPS had left a box on my doorstep.

The Deluxe model has a 45 degree polished surface with a hole drilled through it. The outgoing laser beam passes through that hole on its way to your diagonal. If your optical path is out of collimation, the return beam will hit that surface, and reflect back to you.

From the mirror cell end of the telescope, you see an intense red dot on the 45-degree surface. Instead of running back and forth between the two ends of the telescope, you just turn the screws on your mirror cell, and watch the return beam move back and forth. Because the movement is “real time,” you immediately see which turn of the screw moves the return beam in the correct direction, towards the center hole.

The return beam, if everything is perfectly collimated, will hit the output hole—-with just a little diffused laser light, because the return beam has diverged a bit, and doesn’t all fit back through the hole through the diagonal. The return beam doesn’t exactly disappear, but turns into something like a faint symmetrical spray of red.

I found myself wondering if perhaps the return beam would completely disappear in a shorter focal length telescope, because there would be less divergence of the beam over a shorter distance. After all, in an 8” f/7 reflector, the laser beam has traveled more than 112” (2844 mm)—-enough time for even a laser beam to spread a little. So I pulled out a 3” f/4.5 Newtonian I built some years ago. (That focal ratio on a 3” reflector is not a misprint, but an error in judgment.) The LaserMate™ Deluxe gave the same faint spray of red—and a bit more symmetrical, suggesting that I may have some work to do on my big reflector.

How much of an improvement is the LaserMate™ Deluxe over the traditional laser collimator? Instead of spending ten minutes—and settling for less than perfect—I now can collimate in twenty seconds. I start at the front of the scope, and verify that the outgoing beam is hitting the center spot on the primary. I make whatever secondary position adjustments I need, and then I move to the mirror cell. In almost no time at all, I am done, and ready to observe.

Saving ten minutes doesn’t sound like a big deal—-until you realize that it is now practical to check the collimation when you first open up your scope—and then check it again after the telescope has cooled to ambient air temperatures. I could have done that with a traditional collimator—but I wouldn’t have taken the time to do so, because using a traditional laser collimator was such a nuisance. I also found that collimation on my 8” f/7 reflector changed slightly as I moved the tube in azimuth. This was a hint that I needed to look for and tighten some loose screws that were holding the mirror cell and diagonal.

The LaserMate™ Deluxe is a reasonably attractive piece of construction. The only component that seems cheap or clumsy is the “on” switch, which is just a thumbscrew. On the plus side, it seems like a simple part to replace if you ever lose it. In my experience, products that use conventional switches are nuisances to repair when the switch breaks.

How accurate is it? A traditional laser collimator test is to rotate it in the focuser, and see if the return beam moves. If it moves, the laser isn’t exactly aligned with the body of the collimator. The LaserMate passed this test without difficulty.

Because I had another laser collimator that worked fine, I decided to see if they gave comparable results. After using the LaserMate, I collimated with the MoonLite collimator. I couldn’t see any appreciable difference in results—except how long it took to complete the process.

The LaserMate is attractively priced at $79.95—well worth it for the time it saves me. I suspect that for those who are using a traditional laser collimator—or aren’t using one at all—it will be worth it to you as well.

Clayton E. Cramer is a software engineer in Boise, Idaho.

Click here for more about the Orion Lasermate. -Ed.