Astro-Tech illuminated
multiple reticule finder

The Astro-Tech #ATF multiple reticule finder is a single-power illuminated multiple reticule red-dot finder for astronomy and daylight terrestrial use. The lightweight and compact Astro-Tech finder features a precision ground reflex lens viewing window with minimal parallax; four different reticule patterns; seven brightness levels; and a two-part mounting base for installing the finder on a variety of telescopes.

A lever at the rear of the finder can select any of four different reticule patterns. They include a single dot, such as that found in most traditional red dot finders; a plain crosshair; a circle with four short bars that extend out from the edges of the circle; and a dot within a circle. The reticule patterns project onto a multicoated optical glass viewing-window that is roughly the proportions and shape (but not the actual size!) of a 16 x 9 HDTV screen. Viewing the sky through the window, the red reticule appears superimposed on the sky or daytime landscape. You can choose the reticule pattern that best suits your viewing style and personal preferences. See the actual projected reticules in the feature image below. A supplied rubber cover slips over the glass screen to protect its premium coatings when the scope is not in use.  

The Astro-Tech finder is CNC-machined from solid aluminum for strength and durability, rather than molded of fragile plastic, as are most red-dot finders. The finder is anodized a non-reflective matte black. The finder’s matte black dovetail base is also CNC-machined from aluminum stock.

The supplied two-piece finder base can be used in either of two ways. The mounting stalk by itself is 13.5mm wide and will fit into the finder mounting bracket provided with most larger Astro-Tech and TMB refractors and into the Antares quick release finderscope bracket, as well as into most other brands of quick release bracket shoes.  

If both pieces of the two-piece base are used, the curved base will mount on small Astro-Tech refractors, the TMB-80 refractor, and most William Optics and Stellarvue refractors (all using the 5mm mounting hardware supplied with the base). The underside of the mounting shoe is felt-lined to keep from scratching your telescope’s finish.  

The two-piece base can also be used on most catadioptric telescope rear cells (using the existing telescope trim hardware that seals the accessory mounting holes located at the 1 o’clock position on the telescope’s rear cell). The sharper curvature of the base needed to fit smaller refractor bodies may leave a small cosmetic gap between the underside of the base and a larger catadioptric telescope body, but this will not affect the performance of the finder.  

Click-stop azimuth and altitude hex head adjustment bolts allow you to line up the finder with your main scope optics. The adjustments are very accurate, with each click stop equal to one arc minute of position change. The appropriate hex head wrenches are supplied for both clamping the finder to its base and making the altitude and azimuth adjustments.  

There is a combined on-off switch and rotary brightness level control on top of the finder. The control provides seven click-stop brightness levels, allowing you to match the finder brightness to all lighting conditions and targets, from lining up on the Moon to the locating faint naked eye stars without having the finder brightness overpower the faintest stars.  

The finder uses one user-replaceable 3-volt CR2032 lithium camera battery (supplied). Replacement batteries are readily available at Wal-Mart, Radio Shack, camera stores, etc. 

Just $59.95