Takahashi Micro-fine focuser for Takahashi refractors w/4" focuser

This micro-fine focusing knob replaces one of the standard focusing knobs on all Takahashi refractors using a 4" focuser - the FSQ-106, FS-128F, TOA-130F, FS-152, and TOA-150.

It has dual concentric knurled focusing collars. The larger outer collar focuses the telescope normally. The smaller inner fine focus knob is geared to operate at a 10 to 1 reduction ratio. Ten turns of the smaller fine focus knob turns the larger focusing collar one revolution. This allows focusing that's ten times more precise than even the already smooth and accurate Takahashi focuser can provide. Critical planetary and CCD focusing is markedly easier and more precise with the micro-fine focuser. Ball bearing races in the focuser provide extremely smooth focusing in all temperature conditions. The larger focusing collar can be used at any time to override the fine focus knob and make quick large-scale focus changes.

Except for a user-supplied common Phillips head screwdriver, the micro-fine focuser comes with all the tools and appropriately-sized hardware you will need to install it on your Takahashi 4" focuser refractor. Installation takes only 5-10 minutes. The focuser is designed to be left in place on your scope permanently.