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Telrad Reflex Sight


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I have owned my LX 200 for about 3 months now (it's used) and have had great success using it. Initially, I found that aligning the scope on the two stars for the altazimuth "Goto" mode was difficult with the 8x50 viewfinder provided with the scope.

I finally discovered a three stage approach to positioning an alignment star in the main scope's field of view (or "FOV"). First, I found that I could align the scope quicker by looking down the telescope's optical tube assembly (or "OTA") and roughly aligning the star on two screws on the top of the tube. The star would then be positioned somewhere in the viewfinder's field of view. Second, I would position the scope so the star was in the cross hairs. Finally, I would position the star in the middle of the reticle eyepiece (or "EP") mounted on the scope. (Later, I found the reticle EP not necessary for causal viewing, a regular low or medium power EP worked fine.) Ugh!

About a month ago, I read about various red dot or reflex "heads up" finder devices in The Backyard Astronomer's Guide by T.Dickinson & A. Dyer (A great book.) After looking at several models at the local astro store, I decided to by the Telrad. I'm very pleased with this remarkable device.

Although bulky and boxy (the Volvo of finders), the Telrad has a large viewing window for easier, less obstructed finding. I can't stress how nice the large field of view is. The Telrad generously allows my eye to be at various positions behind the scope but still maintain a star in its central reticle.

The LED sighting rings that your eye sees are spaced at concentric diameters marking 1/2, 2 and 4 degrees. The reticle is brightened or dimmed using the same knob that turns it off and on.

The base to which the Telrad attaches to the OTA uses aggressive double sided tape. The body of the Telrad attaches to this base via two dovetail struts. The Telrad is very secure and easy to remove from the OTA.

Three adjustment screws allowed for very easy alignment with my scope's field of view. To align the Telrad, I simply aligned my scope on a bright star and then adjusted the three Telrad screws until the star is in the middle of the reticle. I like the circular reticle because it does not obliterate the star in it's center, unlike the 8x50 viewfinder cross-hairs. Remarkably, the Telrad remains aligned despite being removed from its base and then replaced on the scope (as you would when transporting the telescope, which I have twice now). I have not had to realign my Telrad since I first aligned it.

Now, aligning my telescope on any particular star is very easy and accurate. I have found that a star centered in the Telrad is always near my telescope's center field of view.

The Telrad also provides a good check on the accuracy of my aligning acumen (veteran astronomers need not read further). Several times I have chosen the wrong alignment star name from the list in the Meade handheld controller for the LX200. Upon looking into the eyepiece, I only find an empty field or unfamiliar stars. A quick glance through the Telrad alerts me to my silly mistake. I then go through the telescope alignment routine once again, which is not nearly as time consuming as before.

A this time, I simply have no use for the 8x50 viewfinder. Perhaps I could use it in the future as some kind of retrofitted auto-guiding scope or give it to the kids as a simple telescope they could use.






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