The ST-80 is a great deal for a low-cost, wide-field telescope (see my page on modifying the ST-80, and it's siblings, to maximize its performance). When I wanted to use it for solar photography, I quickly discovered this lightweight equatorial mount could not handle a severely off-balance load. It would just swing to vertical, no matter how tight you cranked the locks.
This version is equipped with a 1/4 x 20 tripod socket on the bottom, so no balance adjustment is available. Even if I removed the socket, and used tube rings, the main body is so short that it still would not balance.
A few minutes with some scrap oak led to a very serviceable solution. A 1/4 x 20 bolt extends through a square block to mount to the scope. A couple of carriage bolts running horizontally through the block provides a means for mounting the scope block to the base board. I cut a 1/4 inch slot through a 3/4 x 3/4 stick using a router table, and mounted it along the edge of the base board. The carriage bolts extend through the slot and are capped with a couple of knobs. The base board is mounted to the equatorial mount with two 1/4 x 20 carriage bolts running down through the base board and through the factory mounting holes in the mount head.
Copyright © W Berglin 2001 - 2009