Cahill Rooftop Observatory

Equipment Database - SBIG Clear Filter

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SBIG Clear Filter
Adapter Size1.25"
Transmission (Visual)95%
Transmission (CCD)94%

Usable on:

This filter will usually be found mounted inside the ST-9E's filter wheel.

This filter does not actually filter anything, but is designed to have the same thickness and index of refraction as the SBIG Red, Green, and Blue filters. It can therefore be used as a "clear" stop on the filter wheel without forcing the observer to refocus the camera.