Focusers, Mirror Cells, Para-Focal Rings & More

        After twenty years experience as a pattern maker in the aerospace industry, Dave Rubenhagen was "down sized".  Instead of lying down to surrender, Dave setup shop and founded DAR-Astro.
        All of Dave's products are his original designs,  and 100% made in Canada.  Custom modifications for an extra charge is available.  Currently Dave makes focusers in 1.25" and 2", but rounded and flat base, mirror cells from 6" to 12.5", ParaFocal rings (very popular with some owners of Zeiss bino-viewers), and the focusing assembly for the SanJo binocular telescope.
        This page is still under construction and more products will be slowly added.  Right now plans are in the works for larger mirror cells in the 16", 20 and 24" range to be brought out in the 2-3 years, but honestly they exist at this moment only as auto cad drawings.  We will keep you up to date.


DAR-Astro 12.5" mirror cells, top and rear view.  9 point support on the 10" and 12.5", 3 point support on the 8" & 6" size.  We are looking at an 18 point support on the 16" model and perhaps a 27 point support on the 20" and larger models.


DAR focusers.
            Image one shows the 1.25" focusers, one fully retracted, the other fully extended.  Image two shows the 2" focusers.  In each picture, I have placed a Vixen 20mm Lanthanum in beside the focusers for scale.
            The bronze barrel is the coarse focus (9 threads/inch) while the aluminum is the fine focus (20 threads/inch).  Tested operational  at -30C below AFTER being frozen solid for two weeks in a row.    That fact probably does not mean much to many of our world-wide customers, but we have a running joke here that most telescope designers obviously never used their products in a Canadian winter.  For our customers in Canada, Alaska, Russia and the Scandinavian countries, you'll love these focusers in the middle of January - not only do they never freeze up, you can easily use them with gloves on!
            For the rest of our customers in warmer climates, they work great in the summer too.
            These focusers are intended for visual use on newtonian telescopes.  We are working on  a modified version with a locking focus that would be suitable for astro-photo or CCD work.

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