I recently purchased an 8.25" (210mm) Red Dot Artar lens in barrel (circa late 1 960's or early 1970's) and would like to mount a lens shade to the front of the lens. Unfortunately, the filter thread size of the lens appears to be different than all standard filter thread sizes made today. The closest standard size cu rrently being made is 40.5mm, but that is slightly too big.

1. Does anyone know if lens shades were ever made either by Goerz or by any othe r manufacturer that would fit onto the front of the Goerz RD Artar 210mm?

2. Is anyone aware of any other way of attaching a lens shade securely to a lens without screwing it on?

3. I am aware of being able to have an adapter ring custom-made to accommodate a standard filter thread, but I've been quoted $50. as the price it would cost--a nd don't want to spend that much money if I can help it--the lens didn't cost mu ch more than that!

Thank you.