I was just given a Korona VI 5x7 that looks a bit ugly on the outside but inside is beautiful. That got me to finding lenses in my collection which would cover 5x7.
I was given a Klimsch Apo-Ronar 480mm f/9 (made in Western Germany to give you an idea of the age) process lens and I've read these are fantastic performers. Problem with my lens is that the front and rear elements seem to have almost been etched. I encountered a similar look to glass when I purchased my 1972 Mercedes-Benz 220D. The glass had a few decades of maybe hard water or some kind of chemical etching that needed to be removed. I buffed the Mercedes glass and it's been good since.
When I got to looking at the front element of the Apo-Ronar, the coating was badly worn but it also had texture. It was almoat like lacquer and the lens was merely translucent because of this. It would resolve a very diffuse image. I've been carefully polishing this with cerium oxide and this coating is largely gone but I still have a ways to go to get the front surface at least uniform. I see that the glass almost has a bubbly or wavy texture to it and while it is polishing out, it's disconcerting to say the least. It is beginning to resolve a better image but the front element has a long way to go then the rear element will get the same treatment. Has anyone else seen a similar phenomenon on an old lens such as this?
Thanks all.
Phil Forrest