Unmounted Hoya Filter Question

Does anyone happen to know what diameter the glass is in a Hoya 46mm filter? I want to get my 52mm Hoya R72, who's glass diameter unmounted is a hair under 49mm, down to 43mm for a project I'm working on... until it dawned on me that the 46mm filter, unmounted might be just what I am after.

Jacob

Welcome to APUG

Check out (there was a url link here which no longer exists), fourth post down. (Yeah, I just knew someday, somewhere, someone might ask this! )

I don't think I reported the actual dimension though, so let me know if you still need that and I can go measure it.

Jeff

Thank you... I enjoyed your post. I think you are right that the Hoya 46mm is going to have a glass diameter of something pretty close to 43mm. I looked into grinding and/or cutting the 52's glass to size, but in the end decided the best route was to buy a 46mm and take my chances. At least it should be closer, and any mods much easier to make. (As such, I have a 52mm R72 in perfect condition for sale! Hint! ;p)

I emailed Hoya optical Friday, but have not heard back yet. I'll measure it when it comes in (Tuesday?), and leave a note here in case it might be of help to anyone in the future.

"Unfortunately it is hard to find exact dimensions of the glass in commercial filters." - so, so, true!

Jacob

Jacob, it sounds like it is going to work for you - I just measured the optic and found the diameter to be between 42.9mm and 43.0mm (as near as I can measure with my cheapo caliper). Good luck!

Jeff

Awesome, and thank you! That is great news. I find it interesting that you measured just a hair under 43, as I with the 52mm measured just under 49 technically, somewhere between 48.8 and 48.9 mm, but that was beyond the precision I had available to me.

Thank you again!

Jacob