Back in the day, lens cleaning was a front and center concern, with everyone discussing their preferred methods and products. I had a blower brush, tissues, and fluid as part of my kit. But now, ...
I bought this som berthiot 20mm f1.9 lens assuming it was a c-mount but it is much smaller with an elongated screw mount. Can't figure out what type of mount this could be. Here it is compared to ...