Last updated: 22 July 2005
Subject: ETX Green Laser Pointer Sent: Wednesday, July 20, 2005 17:32:06 From: Ray Schmidt (firstname.lastname@example.org) I have been told many times that the main drawback of GoTo Scopes is that you do not learn the sky. Well, my solution to that was to mount a 20mW (for darker sites 5mW would be more than adequate) green laser pointer under the scope, and after the ETX has found the object of interest, I briefly flick the laser on so I can see exactly where it's pointing in relation to other stars and constellations. Note that the laser can also be used for sighting on an object without having to use the finder-scope. The following points are worth noting for anyone wishing to do something similar: 1. The pointer needs to have an end-mounted push-on/push-off switch for accessability, and to avoid wobbling the scope. Alternatively, the switch could be mounted on flying leads for remote control. 2. Fixed nylon screws were used at the front and two adjusters at the rear for lining up with the optical axis. The mounting rings were scavenged from the original laser mount as supplied, although they could easily be made from rings cut from a length of aluminium tubing. 3. The third adjusting screw has been removed and replaced with a coil spring which holds the laser in suspension against the other two adjusters, because of limited space under the OTA. 4. The positioning of the laser is quite critical to enable easy access, without hitting on the base as the OTA elevates. 5. CAUTION: Lasers used carelessly can be dangerous. This is not recommended for use around crowds of people, for example in public displays or large star parties. Ray Schmidt Australia In position ready for use.Mike here: Of course, the standard caution about airplanes and laser beams applies!
Looking from underneath The mount Close-up of tension spring Slung under the OTA The laser in place The mount in place without the laser Regards Ray
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