So who stripped their lense's hood mount?

I wonder if I will get any help with this nasty but apparently infrequent problem: About a year ago I purchased a new 135L. The hoods of my currently nine EF lenses are each a bit different but none had that particular "dry" feel when mounting that I experienced with the 135. While turning fairly easily, the hood would make squealing or slightly grinding noises, and the fit when locked felt just a bit lose compared to other hoods.

I was always concerned about wear on the hood mount and apparently for good reason: Despite very infrequent use of the lens a recent inspection revealed an alarming degradation of its hood mount with dulled, even ground-off areas.

Needless to say, the lens was never exposed to substantial amounts of abrasive dust, and it has been cleaned regularly and thouroughly. Nor did I misalign the hood or something. There's also no obvious defects on the hood.

So what are my options in order to avoid total failure of the bayonet (at least) or even to return the lens to its original state (at best)?

• I might use a bit of silicone grease as a first aid measure to ease the grinding.

• I could replace the hood to see if the problem persists.

• I could send the lens to Canon for a warranty repair. Being in the second year of EU warranty I'd have to prove that Canon was at fault though. Hardly practical.

• I could request a cost estimate for a repair. Judging from reports about the notoriously delicate front ring of the 50L I'd guess a bill of several hundred Euro. (Edit: The 50L's hood mount is known to come off sometimes, not for wear.)

I wonder if any of you experienced any similar problems and how you dealt with it.

Hmm. Never noticed anything like that, but then again, I rarely remove my 50L hood. I might suggest a very careful application of the silicon lubricant, and then just leave the hood in place. Is there a reason you need to frequently remove the hood?

I store my hoods reversed, it's just a matter of space in my pack. I have had that squealing noise with several of my hoods, especially my 24-105. Nothing fits loosely, in fact just the opposite, I'd better start checking to make sure I'm not wearing anything out.

hiketheplanet wrote in post #17141951
Is there a reason you need to frequently remove the hood?

We are talking 135mm L with a 10 cm (just guessing) hood, barely suitable for storage/transportation​. The 50mm was just mentioned for reference.

I ordered a replacement ET-78II hood today to check for any deviations. My best guess is a very unfortunate interaction between a slightly out of spec hood and some microscopic residue of Japanese beach dust (even though other lenses are totally unaffected). The scary thing is: the problem seems to worsen on its own once the surfaces are dulled, despite meticulous cleaning.

You are right Bonpu, the bayonet seems less smooth on the ET-78II then on other hoods (either original Canon or aftermarket) and the rough molding spots in the middle of each bayonet segment are quite pronounced. I smoothed them down somewhat with a wooden dowell and passed a soft graphite pencil tip allround (rather than using grease).

The marring of the lens finish was, by now, only superficial in my case.

Thanks for posting this.

Yep, my 135 f2 L hood is the ET-78II & it's horrible to twist on and off but the inside of my bag is like a Tokyo apartment complex, so it's what I have to do.

Two Hot Shoes wrote in post #17142575
...the inside of my bag is like a Tokyo apartment complex...

Excellent simile.

OP: I had this on an aftermarket hood. There was enough plastic dust coming off of it (from the grinding) that I ended up pitching it quickly, swallowing my penny pinching pride, and buying an OEM version.

I would use bees wax or paraffin for lubrication, not grease.

Or chap stick...

As soon as I saw the title I figured you were talking about the 135L. This is a very, very common problem. It would be interesting if you tried sending it in for repair under warranty. I certainly wouldn't pay for a repair since it will just happen again. I guess you could lubricate it, but then it will probably just fall off, or not lock in place properly anyway.

And no, it does not happen with other hoods, so talk of 50L's etc is mute anyway.

I added some superglue to the inside of the hood and let it dry - added enough friction to keep it on and stop it spinning (at least until the glue wears out).

This is an older lens with a not very good hood attachment. Not sure if a new hood will help though since I can't remember which part of the mechanism gets worn down (on the hood or the lens or both). Good luck in finding a solution.

The hood feeling not really attached on my 135L is something i noticed a few months ago. But i havent used the 135L very much. However i dont think its a big problem as it is attached on doesnt come off so easy...

Also, on my 70-300L the hood everytime squeezes in wrong and i have to do it very careful in order to screw it on correctly..

Is there a difference between ET-78 and ET-78II? I have the latter and it doesn't feel loose, only rough.

I've been doing this for years. Lick the top of your index finger and run it around the inside mount of the lens hood.

yogestee wrote in post #17145923
I've been doing this for years. Lick the top of your index finger and run it around the inside mount of the lens hood.

that's wrong, you are supposed to buy something

garbidz wrote in post #17152767
that's wrong, you are supposed to buy something

Hahahaaaaa....