Leica 90 F1 (Picker X-ray machine only)

[KEH]

Hi Brian,

Curious to know what you know about this lens:

http://www.keh.com/camera/Leica-M-Fixed-Focal-Length-Lenses/1/sku-LM069990377660?r=FE

The description at KEH states:

90 F1 (PICKER X-RAY MACHINE ONLY) (CANADA) 35MM RANGEFINDER MANUAL FOCUS TELEPHOTO LENS

Is this lens convertible to something useful (like Leica M or m4//3)? Seems to be a very appropriate question for the "Mad Gearhead Scientist."

Thanks,
Kirk

[Brian Sweeney]

I've seen this lens on Ebay before, and that is my only knowledge of it. It is "fixed distance", no helical. I've seen an auction where some fixed rings were included to take the place of a helical.

Most lenses for X-Ray machines and CRT's have a very small back-focus. I have a 42mm F0.75 lens, backfocus is so small you might be able to use it with a CCTV type camera. It sits a few millimeters from the image plane. Not enough of an image circle for 35mm.
I'll add these lenses to the list of things to document here.