From the January 2008 issue

Make the BT70 binoculars “go-to”

Mount Orion's binocular telescope to a Celestron mount for ultimate two-eyed observing.
By | Published: January 24, 2008 | Last updated on May 18, 2023

Orion BT70
This image shows an Orion BT70 on a Celestron NexStar SE mount.
Jon Schwartz
As I mentioned in my review of Orion’s BT70 binocular telescope, which appeared in the March 2008 issue of Astronomy, you’ll need a sturdy mount to get the most out of this fine instrument. One owner has come up with a clever way of accomplishing that feat. Jon Schwartz (photec@cnw.com) of Mercer Island, Washington, uses an 8-inch VersaGo dovetail L-arm from Orion (catalog #05048) to mate the BT70 to his Celestron NexStar SE go-to telescope mount.

As he explains, “The Celestron Nexstar SE mount has an adjustable clamp so the telescope tube can be balanced or removed. Loosen the clamp and the telescope tube slides out of the arm’s dovetail base. You’ll then see a plastic nacelle curved to match the circumference of the telescope tube. In order for the BT70 to clear the arm, this has to be removed, which is done by unscrewing its mounting screws. Be aware that removing the nacelle exposes the NexStar mount’s ring gear and drive pinion, which poses no problems as long as you don’t contaminate the grease. For safety, I decided to cover mine with a Plexiglas disk. Then, just rotate the NexStar’s mounting bracket 90° so it’s vertical, slide the L-arm in, lock the thumbscrew securely, and you are set to go.”

Orion BT70
This image shows the NexStar SE arm with L-arm in place and nacelle removed.
Jon Schwartz
Thanks to the BT70’s right-angle eyepieces, you can attach the instrument to many different telescope mounts. After reading about Schwartz’s setup on the Cloudynights.com binocular forum, I attached my test BT70 to my own German equatorial go-to mount and found the two worked together well. I simply attached the binocular’s tripod mounting bracket to a spare dovetail plate I had for the mount, and I was ready to “go-to” in less than 5 minutes.

Imagine, a go-to binocular. What decadent idea will we think of next?