Last updated: 21 February 2009
Sent: Saturday, February 21, 2009 10:43:54 From: Jan M. Hollis (email@example.com) For less than $20 on Amazon, I bought an NCStar Red/Green Dot gun sight, designed for the paintball crowd, to use on my ETX-125EC. The sight is very rugged, made from aluminum, has a clear 25 mm diameter objective, weighs 132 grams, is 104 mm in length, has two different size dovetail settings, and comes in either black or silver. The resulting dot size is a nicely resolved disk approximately 5 arcminutes in diameter. The paintballers complained that the unit is often too dim for daytime use, so I took the chance that it might be fine for astronomy. The battery that comes with it is a 3Volt CR2032. When I got the sight I had to take the battery out and the electronics disk that it sits on to access 4 small screws to loosen the rheostat so that the unit more easily turns on/off and changes between red and green dot brightness settings. At 3 volts the dot is bright enough for daytime use, but I found if you leave the unit on for a day or so, the voltage drops to about 2.8 volts and then it is almost impossible to see the dot in daytime but is just perfect for nighttime use. Subsequently, on the web I found that the discharge curve for CR2032 batteries quickly drops to ~2.8 volts but stays there for hundreds of hours -- no wonder the paintballers are complaining! In any case, I think this particular gun sight makes a very good telescope finder, and pass along these comments for what they're worth. Cheers, Jan M. HollisMike here: How did you mount it to your ETX?
I used 3M VHB double-stick tape (Ace Hardware) with the sight mounting brackets set for the 3/8" dovetail. This tape is clear and very, very tenacious. Attached are two photos of the unit. Also shown in the pictures is a yellow line level for finding Home position....
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