Similar to a finder scope, these guide scopes feature a 1.25" non-rotating helical focuser. The focuser is a standard 1.25" compression ring unit with an external M42 X .75 t-thread. So one can either use the camera's t-thread or a 1.25" nosepiece. These guide scopes have been very popular for guiding a refractor. The 50 mm guide scope fits on either our 50-60 mm finderscope rings or our 50-60 mm guidescope dual ring systems.
These guide scopes now come with a 10 mm threaded extension. Using the threaded extension, this guidescope may be converted into a straight through finderscope! Just install the extension between the focuser and main finderscope tube as shown below and add our optional 1.25” reticle eyepiece. But please note, this guidescope is not designed to work with a diagonal.
The Stellarvue guide scope weighs 18 ounces and works with all of our standard 50 mm ring systems. This guidescope employs the same high quality 210 mm focal length, broadband fully multi-coated objective lens as in our top rated F50 finderscopes. Other fittings are black anodized. Main tube is interior painted in ultra flat black. Focuser is lubricated for improved stability and smoothness. Tube is 54.5 mm in diameter, dew shield is about 58 mm in diameter. The length is 9 1/4” - 9 3/4”.
Some guide cameras have a very short backfocus distance. If you cannot attain focus with your guide camera and need to focus beyond the maximum extension, you may purchase additional STE52 extension tubes to increase the distance between the focuser and objective lens.