[zman]

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Hi,

Having a tough time finding a replacement front lens cap for my Tokina 500 mirror lens. Searched the internet trying to find out what size cap it is, with no avail. Anyone out there know what the size is ? Will a snap-style cap work ?

Thanks again for your help.

[NewportPreacher]

Is there some indication of the filter size anywhere on the lens? Should look like "ØXX," where XX is the filter size in millimeters. I don't know about mirror lenses, but on "regular" lenses, one would get a lens cap for an "XXmm diameter lens" and it would work just fine.

Again, I have no experience w/ mirror lenses, so YMMV.

[zman]

No designation on lens for a filter size. Outside diameter of lens barrel measures 82mm. Will continue a search for a slip-on style lens cover to fit that dimension. Just looking for some additional protection when I carry the lens in my camera bag. Otherwise it's protected well in the Tokina hardcase the lens came in.

Thanks.

[HawaiianOnline]

Measure it to see if a hoodie or neoprene slip on type cover would work. The one in the link will fit a lens that is 4.25 to 4.75 inches in diameter.

[excanonfd]

No designation on lens for a filter size. Outside diameter of lens barrel measures 82mm. Will continue a search for a slip-on style lens cover to fit that dimension. Just looking for some additional protection when I carry the lens in my camera bag. Otherwise it's protected well in the Tokina hardcase the lens came in.

Thanks.

If lens barrel's OD is 82mm, then the filter size should be 77mm, that is if the lens manufacturer has followed standardized filter sizing. Standardized filter ring size is; 49->52->55->58->62->67->72->77->82->87mm. It would be best if you can measure the ID of the lens barrel with a caliper, or if there is a camera shop that sells used goods take the lens there and try to fit some filters on to confirm the exact size.

Best type of cap I've found is a screw on metal lens cap, bit of a pain to get it on and off out in the field but it's discreet, no chance of coming off accidentally and the ultimate protection for the front element. 77mm Screw in Metal Front Lens Cap NEW Sonia Brand | eBay For convenience sake, I only buy these screw in caps for those lenses that do not have centre pinch snap on caps available; larger than 82mm.

Hope this helps,

[zman]

Thanks to all for their suggestions. My Tokina lens hood has internal threads. I measured them to be 72mm and luckily had an old snap front lens cap that fit perfectly.