Loading...

Radioactive Lens -- Leica 50mm f/2 Collapsible Summicron (M39)

10,906 views

Loading...

Loading...

Loading...

Rating is available when the video has been rented.
This feature is not available right now. Please try again later.
Published on Sep 6, 2011

Lens: Ernst Leitz GmbH Wetzlar Summicron f = 5cm Nr 1023xxx (M39/LTM mount -- 1953?)

This video shows the radioactivity from a Leica M39/LTM 50mm f/2 collapsible Summicron camera lens, as measured by a simple geiger counter with a pancake probe.

Apparently some early collapsible Summicron lenses may have used radioactive thorium-containing glass (type SBC?) from Chance Brothers Glass in the UK. In 1954 this glass may have been replaced with non-radioactive (for all practical purposes) Schott LaK9 glass with similar optical properties.




One source says that early Summicrons with thorium are in the following serial number ranges: 920xxx-922xxx, 993xxx-995xxx, 1009xxx, 102xxxx, and 104xxxx.

Loading...

When autoplay is enabled, a suggested video will automatically play next.

Up next


to add this to Watch Later

Add to

Loading playlists...