8mm Forum: Mystery Lens

This is topic Mystery Lens in forum General Yak at 8mm Forum.

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Posted by Bryan Chernick (Member # 1998) on August 08, 2017, 10:22 AM:

I know this has nothing to do with 8mm but I thought there may be someone here that could tell me what this lens goes to. I picked it up with a lot of other film stuff I purchased recently. It's brass and very heavy. It's about 2 inches in diameter.

I opened it up to clean the lenses and found there are two elements separated by about a 1/2 inch with a collar. each element is flat on the side that is exposed on either end of the brass cylinder with about a 1/2 inch of straight glass then convex on the inside. so the two convex ends face each other. The lens element on the end with the collar is slightly smaller than the one on the other end. It seems odd to me that the convex glass is inward facing like that.

It looks like it could be a projector lens but there are no markings on it anywhere, inside and out. Other than the collar there are 4 holes on the side of the barrel that may have been used to mount it on something. It is very heavy for its size.

Posted by William Olson (Member # 2083) on August 08, 2017, 10:39 AM:

It looks like it could possibly be a lens that fits between the light source and the film gate of a film projector. I forget what it's called but it would focus the light source into the aperture of the film gate. I had a DeJur750 that had something just like this.

Posted by Maurice Leakey (Member # 916) on August 08, 2017, 11:06 AM:

It could be a lens from a 35mm cinema projector. The holes might be to locate the focusing mechanism.

Posted by Bryan Chernick (Member # 1998) on August 08, 2017, 12:34 PM:

quote:
It looks like it could possibly be a lens that fits between the light source and the film gate of a film projector. I forget what it's called but it would focus the light source into the aperture of the film gate. I had a DeJur750 that had something just like this.

Thanks William, it looks like it probably is a condenser lens based on it's design. I suspect it would be for a 35mm projector based on its size. Now the question is, what projector or other device could it have come from?

Maxwell view Condenser lens

Maxwell View and Maxwell's Optical Theorems

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