I have just acquired a Rodenstock 210 YSAR in barrel.Any one have any info on this?What is the YSAR all about?The seller assured me it was sharp and will cover 5x7.What is rare earth glass?Was I taken for a ride?THANKS

-- Henry Butler (HBtl@aol.com), February 27, 2001

Answers

The Ysar is Rodenstocks version of the Tessar, I believe.
Rare earth glass is optical glass that has the addition of some Lanthanides in the melt. This increases the refractive index without overly increasing the dispersion (Abbe number) of the glass.
As to whether you were taken for a ride or not depends on how much you paid.

-- Pete Andrews (p.l.andrews@bham.ac.uk), February 28, 2001.