Originally posted by Scott C. . . .
But my question to you all would be, what freaking mount is this thing?! because I want to use it!
Hi, Scott C.
As Aaron28 said, mirror lenses often come with an interchangeable T mount. But I think Sears 500s were sold with fixed mounts.
Are you familiar with Canon's FD mount? I believe your lens has a fixed FD mount. Except your Flickr photos appear to show that part of the mount is missing.
FD is a breech mount with a rotating collar. And I don't see that collar on the lens in your photos. Maybe the collar came off when you removed that teleconverter?
I'm attaching some photos of a Canon FL mount lens I have. FL is also a breech mount, but older than FD. Your lens will look different because it doesn't have any auto stop down hardware since your 500 doesn't have an iris.
My lens - with and without its mount collar (the circled screw stops the collar from rotating too far)
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