Originally Posted by SHOZ
But a 22mm filter will screw onto a 3/4-16 mount. Fits loose though.
There's a 0.116 inch (nearly 1/8 inch) difference between those two thread sizes. I could see a 20 mm threading onto a 3/4 spud, but a 22 mm on a 3/4 spud seems like there wouldn't be any thread engagement. If there's enough thread engagement then it's probably why using the wrong filter can cause the wrong filter to blow off the mount.
But a 22mm filter will screw onto a 3/4-16 mount. Fits loose though.
There's a 0.116 inch (nearly 1/8 inch) difference between those two thread sizes. I could see a 20 mm threading onto a 3/4 spud, but a 22 mm on a 3/4 spud seems like there wouldn't be any thread engagement. If there's enough thread engagement then it's probably why using the wrong filter can cause the wrong filter to blow off the mount.