Is my Taron viewfinder radioactive?

[dak]

I have recently purchased a nice Taron external viewfinder with framelines for 35/85 mm. Its optics, however, are so yellow (almost gold) that I wonder if there is no some thorium in it. I've heard about thorium in microscopes eyepieces. Any idea if it was used in camera finders as well, or it was always banned?

 

[Phil_F_NM]

Viewfinder optics which are yellow were either done from the factory to increase contrast (this is usually in rangefinder optics) or due to aging balsam cement. If it is a non-RF viewfinder, it is probably just balsam cement aging, but it could be coating as well. Rare earth glass was very expensive and almost certainly not used in viewfinder optics, as they do not require the refractive index for image drawing, since they are only used for composition, not to project the image onto film itself.

Phil Forrest

 

[mpaniagua]

Pretty unlikely, since, like Phil says, VF don't require the refractive properties that rare earth/radiotive elements provide.

I would say you are safe and won't grow a third eye 😉

 

[Franko]

This is comforting to hear. One of these finders is more or less welded to my IIIf. No third eye yet but it's hard to explain my forked tongue.

 

[dak]

I can live without a third eye, but a third arm would be handy when fiddling with all these bottom loaders and removable back cameras. Thanks, guys!