What focal reducer is this?

Does anyone know what kind of focal reducer this is? Thanks, Chris

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Chris
I have one that came as part of a Celestron assembly with an SCT to T thread adaptor in front and a prism diagonal behind to provide a .5 focal reduction at the eyepiece. I have used it in front of a low light video camera (with 1/3" CCD) and was getting about a .5 reduction.

I hope this helps.
Steven Jindra

That is the f5 telecompressor. Celestron and Orion both carried these. (Don't know if Meade ever made any.) These were common prior to the f6.3 reducer/corrector. Celestron originally sold them for photography, but later married them with a diagonal and a shorter tube (shorter than the standard T adapter they sold) and sold them as a visual f5 adapter (Late 70's, early 80s). With a 35mm film plane, these produced a circular image with some curvature at the edge. The reducer/corrector was developed to increase the field and provide better edge correction. When used with the original Celestron off axis guider, an extension tube was often needed as these units went after the guide pickoff prism and the focus change required that the eyepiece be placed about 1.5" further out.