Did I get a bad copy of the 135mm f/2???

I just received my new 135 f/2 when I got home from work. I was so happy and try it out immediately. It appears that the AF is a little slow. I originally thought that there might not be enough light, but after a compared it to my 17-40mm, it's even slow than the 17-40mm. Is it possible that the 135 slower than the 17-40mm, or I just got a bad copy???

Also, I suspect that the AF is not as accurate as it should be, what is the best way to test it?

Any suggestions and inputs would be appreciated.

Thanks.

The AF on the 135L should be as fast, if not faster, than the 17-40L.
Also, the AF on the one I had was more accurate than on all of my other lenses.

I had to send mine in for a tune up...it wasn't focusing well when I first got it. Now it is very zippy!

"Also, I suspect that the AF is not as accurate as it should be, what is the best way to test it?"

Find a brickwall and stand at an angle to the wall - say 45 degrees. Select the largest aperture (f2) and the center focus-point in the camera menu. Halfpres the shutter for autofocus until you hear the beep-sound. Fully press the shutter to take a picture.

Upload the picture in your favourite photoediting-program. Find the center of the picture and look at it at 100 %. See if it is the sharpest part of the picture. If not your lens or your camera has a problem with autofocus.

To test any lens/camera for Focusing issues, follow the this link, it´s the best one (and I have used/tested 3 or 4 diffetrent test charts/procedures):

http://www.canon-dslr.com …/Canon_SLR_Focu​s_Test.htm

Good luck

I found with my 135 that it is easy to be misled when using wide aperatures. At F/2 and when the subject is close, the depth of acceptable focus is so shallow that the overall image is soft -- softer than you might expect. This took some time to get used to. I had no questions about the speed of autofocus.

Thanks all for your input, I will try to do some sort of testing as soon as I can.

Mareen - do you suggest that I send the lens back to Canon if there really is a problem?

Quite frankly, I would just return the lens if I could easily buy another one. However, I spent a few weeks to look for a dealer who had it on stock. Not everyone is carrying this lens unfortunately. Since I want to get my triple rebate, I think I just cannot afford waiting for another few weeks. Just painful

Thanks.