Oh No! my precious 100-400 L !!!! (1 Viewer)

[John In Ireland]

The locking ring on my 100-400L will no longer work! When it's around my neck it is hanging at full 400mm. It will no longer lock. I saw tiny pieces of black rubber or something coming from it now and again. Now its totally gone, will not lock at all. Anyone else had this problem???

 

[Bananafishbones]

The locking ring on my 100-400L will no longer work! When it's around my neck it is hanging at full 400mm. It will no longer lock. I saw tiny pieces of black rubber or something coming from it now and again. Now its totally gone, will not lock at all. Anyone else had this problem???

Not yet, but I would get it sent away quickly as you dont know where the other black bits a currently lodged. May be the cheaper option short term

Good luck

 

[Marcus Conway - ebirder]

Mine hasn't locked for years

 

[Jaff]

When I had mine some of the rubber became visible and I cut it away with a knife but it still locked ok. However I believe this is a comminsh fault with these lenses as my dad's lens doesn't lock anymore. He was talking about getting it fixed but I don't know if he's gone through with it. He did ring fixation for a rough estimate after giving them a description of the problem but according to him fixation don't do that over the phone anymore and you have to actually send them the lens for them to give you an estimate of the repair. Seems a bit harsh paying the postage and everything if you find it's expensive to fix and they service the lens at the same time which adds a fair chunk of money to the bill.

 

[Huntso]

Canon at Elstree usually do a fixed fee of £102 for lens repair

Known fault with the black stuff and ball bearings, best to get it looked at in case of any internal problems with broken bits

 

[Keith Reeder]

Mine went like that John, but I improvised a solution by sticking a couple of bits of clear tape (since replaced with a round clear bike-frame protector patch - see attached) near the top of the lens barrel to give the locking mechanism something to grip onto.

Works fine for me - at least I can lock it securely at the short end.

 

[Marcus Conway - ebirder]

Mine went like that John, but I improvised a solution by sticking a couple of bits of clear tape (since replaced with a round clear bike-frame protector patch - see attached) near the top of the lens barrel to give the locking mechanism something to grip onto.

Works fine for me - at least I can lock it securely at the short end.

Ingenious!

 

[tdodd]

It happened to mine. After about two years of careful ownership I noticed flecks of black "tape" emerging from the sliding mechanism. A year further on the lens would no longer lock tightly. Other than that it was still working perfectly well. I took it into Canon at Elstree and they fixed the problem and calibrated the lens fully against my 7D and 1D3 for a fixed price of £127 including VAT and delivery. The fixed price repair includes six (or is it three, I think six) months warranty on the entire lens, not just what was repaired, so if the AF or IS or anything else breaks within the warranty period it is covered. The lens is now better than new.

I believe the problem is caused by one of two things -

1. If you get the lens wet then water can seep into the sliding mechanism and cause harm to that "tape". I think it is actually nothing more robust than paper.

2. If you force the lens to slide when you already have the mechanism tightened then you can rip into the tape/paper and over time it disintegrates. Same result.

I've always been careful to keep the lens dry, and in the event of a couple of spots hitting the lens I have avoided pumping it until dry. I guess over the years I might have operated the zoom when the tension was slightly too tight and as a result have paid the price. I guess it is a weak point in the design and it pays to take extra care not to abuse it.

 

[Overread]

I wonder if its a known design fault and only the result of regular use of the item could you claim for repair under warranty? I know that the EU has pushed some changes in the way Warranties work these days (eg we get 2 years default not 1 year - though most shops don't like to tell us ) and there is something in the paperwork now about products having an expectancy to function for a reasonable time through normal use.

 

[John In Ireland]

I wonder if its a known design fault and only the result of regular use of the item could you claim for repair under warranty? I know that the EU has pushed some changes in the way Warranties work these days (eg we get 2 years default not 1 year - though most shops don't like to tell us ) and there is something in the paperwork now about products having an expectancy to function for a reasonable time through normal use.

I wonder? I would like to know where to start on this one. Just looked at my receipt. 1st February 2008. Hmm.. seems a bit of a long shot.

 

[John In Ireland]

Mine went like that John, but I improvised a solution by sticking a couple of bits of clear tape (since replaced with a round clear bike-frame protector patch - see attached) near the top of the lens barrel to give the locking mechanism something to grip onto.

Works fine for me - at least I can lock it securely at the short end.

Hey presto! .... Thanks for that Keith. It at least gives me a short fix for a time.

 

[Overread]

I wonder? I would like to know where to start on this one. Just looked at my receipt. 1st February 2008. Hmm.. seems a bit of a long shot.

Do you have a Trading Standards or some similar government/independent group? They would be the best people to ask for specific advice on what your options are.

 

[Huntso]

since replaced with a round clear bike-frame protector patch

From the looks of it the glueless cycle puncture repair patches would also work and might be easier to get hold of. I use them to protect from rubbing my bike frame, Park ones are very good

Good fix from Keith, not so good they use such shoddy workmanship in a thousand pound lens

 

[Keith Reeder]

Honestly, I don't see there being much chance of making an approach to Trading Standards stick.

As Tim says above, the material is apparently nothing more than a treated paper; and it seems to last most people at least two years. Certainly that's when I first started to see flakes of "black stuff" appearing on my lens - but it still functioned for a good while after this evidence started to appear, and it didn't become a "problem", if you can call it that, until about three years in.

Now I use my 100-400mm at all sorts of focal lengths, and - as Tim observes - I almost certainly haven't diligently loosened the locking ring completely before every such zooming action, so I might well have contributed to the eventual failure of the tape; it would be hard to provide a compelling argument that two/three years isn't a "reasonable" amount of time for the component to last, given how much variation there will be in how (and how carefully) the lens is used from one owner to another. I've got a pal who has had his 100-400mm as long as I've have mine (since 2006) and his has shown no signs of this issue.

Besides, my "fix" has been perfectly functional for a couple of years now, so it's not a critical failure anyway, just a nuisance - although I might feel differently if a big piece of black tape was spreadeagled over a lens element! - and one to put down to experience.

Having said all that, I'm sure that Canon could come up with a more durable alternative to treated paper..!

 

[Keith Reeder]

From the looks of it the glueless cycle puncture repair patches would also work and might be easier to get hold of.

Possibly too thick, and probably too permanent, Huntso.

 

[John In Ireland]

I improvised a solution by sticking a couple of bits of clear tape (since replaced with a round clear bike-frame protector patch - see attached) Works fine for me - at least I can lock it securely at the short end.

Limping along now with clear sticky tape. Never heard of a bike-frame protector patch. What are they used for and where can I get one?

 

[Keith Reeder]

http://www.stif.co.uk/mtb/product/system-ex-clear-frame-protectors/4505

I had some of these lying about (I'm a keen mountain biker and actually use these things for their intended purpose), so if the price here seems a bit steep I'd suggest sticking with (no pun intended) whatever you're using now, John: if the cosmetic end-result isn't that great, stick the tape on the underside of the barrel - it will have exactly the same effect but not be visible to a casual view.

As tapes go, waterproof tape like this: http://www.amazon.co.uk/50mm-Waterproof-Weather-Proofing-Tape/dp/B002ZHN8U0 is probably best, all told - and it has plenty of other uses, of course.

 

[Huntso]

Possibly too thick, and probably too permanent, Huntso

Fair enough Keith, not sure how thick they are in comparison although thinner than the useless carbon Pace protector patch
Work a treat on the headtube of my mountain bike and they come off cleanly with a drop or two of citrus degreaser

 

[John In Ireland]

I can see a few minute black particles through the viewfinder but doesn't seem to be reproduced in a photograph.

 

[tdodd]

I can see a few minute black particles through the viewfinder but doesn't seem to be reproduced in a photograph.

That's just grot in the viewfinder and on the focusing screen. The black bits we are talking about exit the lens where the outer and inner barrel slide over each other when you zoom. Even if bits fell internally they would be so far out of focus that you would never notice them.