The Testar 60mm Guide Scope has a focal length of 240mm and a focal ratio of f/4. The objective is a fully multi-coated achromatic doublet for a greater optical precision. The border of the lenses are blackened to deliver a higher contrast. The 69mm support rings have 3 screws with a nylon tip for a perfect alignment with the main telescope. Having the guide scope aligned to the main telescope increases the guiding accuracy and it reduces the field rotation displayed in the capturing camera. The mini dovetail bar can be firmly mounted on any standard finder scope bracket so you do not require any extra piggy back dovetail bar on top of your telescope. The 31.8mm / 1.25" non-rotary helical focuser permits a micrometric focusing adjustment while a quick release draw tube offers an initial coarse focusing. Designed to use with many guiding cameras it can be used as a great optical finder by adding a 31.8mm diameter eyepiece. This 60mm compact guide scope has an accurate helical focuser that keeps the orientation of the connected camera.Note that with rotative focusers the cables of the guide camera could get twisted while focusing. The precision helical focuser has 8mm of travel while the fast focus device has a 35mm excursion. Specifications Objective lens diameter 60 mm Focal length 240 mm Camera/eyepiece connection 1.25" and male M42 Weight 790 gr Max tube length 270 mm (focuser fully extended) Focus travel 0~35 mm Focuser type Non-rotative micrometric with locking screw Dovetail Specifications 30.8 mm x 89 mm - fits finder scope brackets Dovetail threads 1 x 1/4" , 2 x M8 female thread Included items Guide scope 60mm Tube rings Objective lens cap Eyepiece cap Mini dovetail bar for finder scope brackets 6 x nylon tipped screws 2 x bolts for dovetail-tube rings connection
