70-200 F4 L owners - need your help

I am getting a lot of soft pictures with my 70-200 F4L, I dont understand why, I thought it would be sharper. Here is some examples at 200mm, f4, and on a tripod. I took about 10 in a row and they are all this soft, the cat was just sitting there not moving at all. I am getting lots of soft pictures with it, but its particularly bad at 200mm wide open. Am I expecting too much of it? Do all of lenses look so bad wide open at full zoom?
I have done some focus tests on it, seems to be focusing fine.

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I always shot with mine wide open and obtain very sharp images. I suspect it's front focusing. The dry leaf in the front appears to be more in focus. Have you tried any focusing tests?? Maybe you should if you haven't don't so.

It's very abnormal for a lens like this to produce such results...although you did run focusing tests, it is possible that the lens is indeed back/ front-focusing but didn't reveal it because the test wasn't run extensively or correctly. If this lens is new, I'd suggest returning it and trying another piece.

I have to agree _ is does look soft. I've gotten very nice results at f/4 with mine.

Are you using a filter?
I've had very bad experiences with my 70-200 f/4 L and filters.They just don't mix. If so remove it and test again.

My first copy back focussed slightly but that doesn't seem to be your problem. The second copy was fine and is still sharp at 100%. Bracing and light are critical.
Were you tripping the shutter by hand or with a remote?
Are you sure the cat didn't move? - the ground and leaf look sharper than the cat's face.

I'd say don't give up on it yet - do more stringent focus tests and make certain that the softness can't be attributed camera shake.

The leaves on the floor definitely look more in focus than the cats face.

Yeah, my copy's pretty good too. Like everyone said, that's what I noticed with the closer crop, the ground and leaves look pretty sharp.

Oh, just a suggestion too, but just in case...what AF point are you using?

Hi Shniks;

I agree, it´s front focusing clearly. I have had a similar expirience with my 70-200 f/4, but in my case was back focusing: My nice wife coming out from the sea in the beach, central AF focus selected, sunny day, no way to miss that (she weared a black bikini), 3 shots in the row; when I see the pictures arrived the deception: My wife OOF and the sea waves behind her crystal clear.

I suggest you to use the focus test charts to confirm the problem. If the lens is new, send it back. I did it and I receive a brand new from Canon razor sharp. If is old, send it to calibrate.

Good luck.

Shniks,
Before you assume focusing problems, try using partial metering. Evaluative may be too broad for this subject. I had a 70-200f/4 and it was tack sharp, but any lens will benefit from stopping down a bit. Also, take shots of static subjects. A cat's movements can be very subtle, it's possible she was moving and you just didn't notice. Don't rely too heavily on your camera's autofocus to be right every time, it won't be. When I take shots of someone or something, I use the center focus point and partial metering. At close distances, this will help get into focus what you aim at. Good luck.

Good point. Perhaps the lens tried to lock focus on the ground instead of the cat. Also, it might be a little silly to mention, and I know it's probably not the case with you, but avoid zooming in or out after you have locked focus on your subject.

Shniks,
I'd like to elaborate on my previous post concerning auto-focus. 90% of all so called back/front focusing issues are really people relying too much on their camera's auto systems. Auto focus can only read what it sees in a given scene, it can't read our minds. Using the picture of the cat as an example, without selecting a focus point, the camera's auto focus will just try to focus on the part of the scene with the highest contrast. It decided that the leaves under her face were a better target. Simply centering her face in the scene won't guarantee it will be in focus. If the center focus point had been selected, the camera would have been forced to focus on that area and her face would be in focus.
I think with all the capabilities of modern SLRs, people have come to rely a little too much on the camera to do all the work. Also they tend to think that if things don't come out right it's the cameras fault not theirs. It's only a camera and demands a lot of user involvement. I believe that it's not our gear that makes us good or bad photographers, but rather whether or not we can learn to master that gear to accomplish our goals.
I hope this helps and I hope you don't think I'm talking down to you. The learning process in this field is on-going. I'm new to this forum but have had this discussion in other forums where I've learned so much over the years from many good people.
Good luck with your 70-200, it's a great lens.

The problem could be that there is not a lot of contrast on the cat. It is so much the same color and AF needs contrast to focus best. Try it with a subject with more contrast.

Sorry to say i believe that lens is either front focusing or you haven't used the center focus point, allowing the lens to choose the area of most contrast which it decided it was the leafes in the ground.

The 70-200mm should be what you expected: Fantasticly Sharp, even wide open at full 200mm. Only issue can be the small DOF at 200mm f/4, but even that is what it should be.

Thanks for the replies, I knew I could expect more from this lens. I used the centre focus point so that shouldnt be the issue. Funny thing is, every time I do focus tests it focuses perfectly, so I am unsure what is happening. Maybe it was camera shake, or maybe it front focused this time for some reason. I will do more tests and take it to Canon if it continues to perform badly. Thanks for the reassurance!