Let down by L series

[nighthawk]

I was lucky enough to take possession of a new 17-40 L lens for my camera about 4 days ago, but it wasn't until today I managed to get it on the camera and do some shots with it.

All started well, but I needed to switch to manual focus, and the thing just will not STOP auto focusing!

with the switch "clicked" into the MF position it can't help itself from attempting to focus on what it thinks is the right point. In practice though it doesn't manage to get it right and ends up with a missed shot.

For such an expensive lens, i'm extremely annoyed!!

Any of our esteemed snappers been let down by Canon's L series before, or is 2005 going to be a baaaaaaaad year for me when everything goes wrong?

[parrot of doom]

A simple botch would be to find which contacts on the lens power the auto focus, and stick a small square of sellotape over one of them.

[srider]

nighthawk said:

I was lucky enough to take possession of a new 17-40 L lens for my camera about 4 days ago, but it wasn't until today I managed to get it on the camera and do some shots with it. All started well, but I needed to switch to manual focus, and the thing just will not STOP auto focusing! with the switch "clicked" into the MF position it can't help itself from attempting to focus on what it thinks is the right point. In practice though it doesn't manage to get it right and ends up with a missed shot. For such an expensive lens, i'm extremely annoyed!! Any of our esteemed snappers been let down by Canon's L series before, or is 2005 going to be a baaaaaaaad year for me when everything goes wrong?

Sounds like it's faulty. There should be no attempt to AF with the switch to MF.

[srider]

parrot of doom said:

A simple botch would be to find which contacts on the lens power the auto focus, and stick a small square of sellotape over one of them.

Great idea, get a new £600 lens, and botch it with sellotape to get MF

[EmmaP]

Sounds odd. Must be a fault. I'd take it back and get it sorted. If you start messing around with contacts you will probably ruin your chances of getting it fixed under the warranty.

[parrot of doom]

srider said:

parrot of doom said: A simple botch would be to find which contacts on the lens power the auto focus, and stick a small square of sellotape over one of them. Great idea, get a new £600 lens, and botch it with sellotape to get MF

You'll note the careful use of the word 'botch'.

[murph7355]

Give the contacts a quick clean before sending it back, on both the camera and the lens. It could just be there's some dirt on it (if you haven't done this already).

If there's still no joy, send it back as faulty.

I only have 1 L lens so far and it's fine. Not heard of any others experiencing faults either but I'm sure they must happen.

Look on the bright side - perhaps this is the only bit of bad luck you'll get in 2005

[V6GTO]

Don't have this problem with my 100-400L IS.

Martin.

[nighthawk]

The contacts are very clean with no signs of any marks.

neither my 18-55 or the 75-300 IS do this, so it must be within the lens.

Kind of glad i didn't save the extra £11 by buying off the net, because it's going back to the shop within the next hour