The filter slide for the Schuler Astroimaging BVRI filters is made of ABS plastic with an overlay of HDPE to retain the filters in the cells. The slide glides in white HDPE guides with a detent mechanism to hold the filter slide in place. The internal parts of the tube needed to be cut away to fit the filters in place. Currently the filters need to be changed manually, requiring a step ladder to reach them most of the time.
The filters in the slide are B (blue), Visual (green), R (red) and I (infra-red). The I filter is the same diameter as the others but the clouds were not visible through it, only the sun was bright enough to see anything in the photo.
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