Telescope-Accessories-Askar M54 Backfocus Adjuster

Askar M54 Backfocus Adjuster

Back focus can be a challenge for astrophotographers utilizing different combinations of equipment. This backfocus adjuster from Askar is 18 mm in length, and allows you to adjust the backspacing distance of your camera up to ± 2 mm. Essentially, you are provided with a spacer that varies in width from 16-20 mm!

This CNC machined M54 Backfocus Adjuster from Askar has a telescope-side female thread of M54x0.75, with a camera-side male thread of M54x0.75. To alter your backspacing, simply rotate this Askar adjuster. Each index mark denotes 0.05 mm of adjustment, making it easy to find the perfect backspacing distance for optics that require such precision. Once the ideal distance is found, twist the locking screw to hold your backfocus in place.