I apologize if this has been covered before because I've had no luck in finding the answer.
I recently purchased a Retina IIIc and I would like to use common filters for B&W film with the camera such as red, yellow, orange, and green. Everything I have read to this point says that the filter threads of the IIIc are 29.5mm. Searching the internet tells me that I may never find any filters with that thread.
The best I can come up with on my own is a 29.5 to 37mm step up ring with an additional 37 to 52mm step up ring. That will allow me to purchase filters at a more reasonable price as it is a far more common thread diameter.
If there is a better way to work around this I'd love to hear it?