I am having an issue where my 5-6 year old 17-55mm lens is vibrating/shaking rapidly with my C100. This just started happening while I was in Vegas for CES. I shut down the camera and removed the lens and then put it back on and it was fine for a while. But 2 additional times is did this spontaneously. It's a fast vibration like the lens/camera are sitting on an electric sander. Turning IS off fixes it but obviously I have not IS then.

I tend to think this is the lens but I thought I would ask if anybody here has seen this behavior before. I haven't seen it on any of my other IS lenses but I also use the 17-55mm most of the time.

Even though it appears to be working now I have a fear that this could happen again at the worst time and ruin a critical shot. Until I get it fixed I feel like I will be on pins and needles, however I have had experiences in the past where I send items that are having intermittent problems to Canon service and they send back saying nothing is wrong. Probably because the item didn't malfunction while they tested it.

Thanks for any advice.

I have the Canon 17-55mm F2.8, amongst many Canon lenses. It is my workhorse lens on my s35 cams for sure.

Not had this fault (or heard of this before) but I did recently have a different fault with my 5 year old Canon 10-22mm F3.5 (a non IS lens).

It turns out my lens fault was caused by a fatigue crack in the internal ribbon cable that Canon (zoom) lenses have. I guess this flexible cable connects the contacts on the lens mount to a moveable sub-assembly inside the zoom lens, and over time they can become fragile and crack. In my case I ended up with a non-working iris. It cost me just under £200 to get the lens repaired (by one of three Canon certified repair centres here in the UK). It was a sudden/complete failure (i.e. easy to diagnose), but only after a couple of "strange" episodes a few days before....

So why is this relevant? Well I mention it as during the process I learnt that ribbon cables failing in Canon lenses are, whilst not common, certainly not unheard of - even in top of the line L lenses.

Maybe it is something to do with the ribbon cable in your lens? It might be (at the moment) just a hairline crack in the wires within the ribbon that control the IS motor...or maybe it is something else entirely....I am no lens technician.

The other thing worth mentioning is that putting the lens on my Canon 7D body gave me a diagnostic error code...which I then googled and started learning the above! If you have a Canon DSLR (or a friend with one) it might be worth seeing if you get a code displayed when it does this fault?

Anyone got any other ideas?

I do have 7d. I will try this and see if it generates any codes. Thanks for the idea.

I own the lens and I think it would be crazy to ignore such a problem if it's your primary lens. I'd get on the phone with a Canon Service tech instead of waiting for it fail on a job.

Well I tried it on my 7D and there are no error codes however whenever I press the shutter button and the image stabilizer engages the video becomes very shaky. So... I guess I am calling Canon service in the morning. Thanks guys. I'll let you know when I get it back and how easy and quick it was. (being hopefully optimistic here).