You are here: Home : Library

Lens redioactivity - measurements
Actinometry of old lenses

Lens Result Comment
Yashinon 1:1.8 f=5.5cm 81nSv/h too old for this problem?
Yashinon-DX 28mm 1:2.8 210nSv/h
Yashinon-DX 50mm 1:1.4 81nSv/h
Yashinon-DX 50mm 1:1.7 84nSv/h (Version with chrome ring)
Yashinon-DX 50mm 1:1.7 84nSv/h (black version)
Yashinon-DX 50mm 1:2 66nSv/h (chrome version)
Yashinon 55mm 1:1.2 981nSv/h *
Yashinon-DS 50mm 1:1.4 680nSv/h
Yashinon-DS 28mm 1:2.8 86nSv/h
Yashinon-DS 50mm 1:1.7 762nSv/h
Yashinon-DS 50mm 1:1.9 76nSv/h
Yashinon-DS 50mm 1:2 95nSv/h
Yashinon DS-M 28mm 1:2.8 80nSv/h a surprise as it's a winde angle lens - maybe too recent or the new 8/7 formula works without special glass
Yashinon DS-M 50mm 1:1.4 572nSv/h
Yashinon DS-M 50mm 1:1.7 798nSv/h
Yashinon DS-M 55mm 1:1.2 1056nSv/h *
Yashinon DS-M 1:4 200mm 86nSv/h as expected: a tele lens doesn't need glass with high refractive index
Yashikor 28mm 1:2.8 80nSv/h
Yashica DSB 28mm 1:2.8 82nSv/h
Yashica DSB 50mm 1:1.9 81nSv/h
Yashica ML 50mm 1:1.4 83nSv/h
Yashica ML 50mm 1:2 81nSv/h
Porst MC 1:2,8/28mm H 79nSv/h
RMC Tokina 24mm 1:2.8 83nSv/h
Super-Takumar 55mm 1:2 380nSv/h it's not only Yashica ...
Topcon UV Topcor 50mm 1:2 283nSv/h *

Remark I : the mesurement has been carried out directly behind the rear element - result is without substraction of natural radiation (ca. 83nSv/h for most lenses, 64nSv/h for lenses marked with "*" in the comments).

Remark II : this is by no means to be understood as a scientific report :-)

Reference for the amount of natural radiation: Jährlicher Bericht 2004 gemäß Strahlenschutzvorsorgegesetz ("Yearly report as orderd by German Radiation Protection Precaution Law")

This page is continuously updated with new results
(Last update: 3.7.07 - 21:01 MESZ)