jeep_daddy Loc: Prescott AZ

It's simply to shave weight off the lens assembly. The original EF500 f/4 lens was about 8.5lbs and to sell a new MK II lens they had to do something to shave weight off so that they could justify selling it for $3,800 more than the original. Anywhere they can save weight, they did...

Gitchigumi Loc: Wake Forest, NC

LOL! 👍🤓👍

imagemeister Loc: mid east Florida

speters Loc: Grangeville/Idaho

My guess its for those folks that like to add straps to their lenses, this could be used to loop it through!

Hsch39 Loc: Northbrook, Illinois

I'm surprised no-one is using this safety feature. It's there to secure the camera and lens with an additional strap.

imagemeister Loc: mid east Florida

Hoggers here seem to like to live dangerously ! .....

Picture Taker Loc: Michigan Thumb

A strap.

patrick M

The canon mount had a lock mount but that was a little different. So the correct thing to do is contact canon by chat. They will tell you or go online to canon support and look up mounting

cjc2 Loc: Hellertown PA

It's not there by accident which suggests it's for some accessory like a carrying strap, especially if there's a second one somewhere else on the lens. Might try the information that came with the lens or get that on-line. Best of luck.

Doc Barry Loc: Huntsville, Alabama USA

Nope, strap mounts on the lens body.

jim quist Loc: Missouri

GAFL

patrick M

Contacted canon support they don’t know some type of manufacturing deed

amfoto1 Loc: San Jose, Calif. USA

I don't think it's for strap attachments. At least in the case of Canon lenses, all the ones with that hole in the tripod foot already have two strap attachment lugs on the side of the barrel. So there's no need for another one on the tripod foot. I wouldn't thing that a very good place for a strap attachment anyway. It would put a lot of strain on the tripod ring, carrying it by a strap attached there.

Maybe it's intended as way to attach a security cable, to prevent theft, since it's found on the "high dollar" lenses. However, it wouldn't be possible to use it when the lens is on a tripod (whether or not any lens plate is being used for quick release). NOPE... According to the user manuals, all (?) the lenses with that "slot" in the tripod foot also have a "Kensington" style safety cable slot (it's hidden under a cover on the knob that tightens the tripod mounting ring).

Maybe it's intended as a way to attach the foot for storage when it's removed from the lens. NOPE... some (many? most?) of the lenses with it have non-rmovable tripod ring feet.

Or maybe it's there as a place to hang your lens while it's drying out after you wash the mud off it.

Hey, maybe it's a "church key", for use popping the caps off beer bottles.

Or, it's a place for scuba divers to tie a rope while retrieving the lens you dropped in the lake or ocean.

P.S. I have RTFM of a number of the Canon lenses that have that slot in the tripod foot. Nowhere is there any use for it mentioned. I certainly wouldn't use it to attach a strap! There are much safer mounting points for a strap, on all the lenses I've been able to check.

cjc2 Loc: Hellertown PA

Although I'm inclined to go with your last thought, this is going to remain one of the great mysteries of life. I'm still sticking with some sort of strap connection although I have seen flash gear attaching points on feet made by the likes of RRS. As I am a Nikon shooter, I can't check mine out. The mystery remains...

imagemeister Loc: mid east Florida

The 100-400 II has the slot and no other attachment locations on the body of the lens .....

The slot is more for tethering when NOT on a tripod ....

What is RTFM ?? ...
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