Using my 10D, I tried out two different 70-200 F2.8 IS

Using my 10D, I tried out two different 70-200 F2.8 IS lenses. Both copies of the lenses had sharp focus on people standing still , but soft focus on those walking toward me ( at normal pace ).

I had IS turned on, 1/200 sec., usually f8 or f11, ISO 200 and set in AI SERVO focus mode. Can someone tell me what is going on here, please?
1) I can't imagine both 70-200s were bad.
2) Was the AI SERVO mode not used correctly.
3) Is the 10D at fault?

What do I look for?

Thanks

How many shots did you take in succession? Usually, when the subject is moving towards you and you are using AI Servo, the camera acts in shutter release priority mode for the first picture and then focus priority mode in the subsequent pictures. What that means is that most times, your first picture will be out of focus because the camera will fire even when focus has not been achieved. The subsequent pictures should look better because they'll be in focus.

And.. even when everything works the way it should... in that situation.. you should be willing to except a percentage of oof shots...

A subject moving closer is easy to fool an AF system.

In this case I do not think you have "bad" lenses.. it is the entire focus systems limitations that are failing you.

I took a few shots, 2 or 3, each time but they are all equally soft. However, thanks for that tip !

Is them 'orses 'oofs

Are the 'Orses Out Of Focus?

I assume you mean 2 or 3 in bursts with a single press of the shutter release button, right? If so, then it's odd that they all came out OOF.

Just got the 70-200 4L but without IS and let me tell you i couldn't belive how much i shake when i crank it to 200! I even tried a monopod and i still got camera shake.I think i have to buy a tripod (oh santa) Is this normal or should i cut down the coffee

Are you an elph? the 70-200 is pretty damn light. Imagine if you were shooting with 2.8, they are heavier and aren't as sharp as the f4, even if it's very minor difference.

Time to start some arm curls

The 70-200 f/2.8 isn't as sharp as the 70-200 f/4? What makes you say that?

It just isn't. Don't get me wrong, it's not a big differnce, but there is one.

PaceAce, I was in single shot mode and waited about 1 to 2 secs. between shots.

jc

OK, that may explain it then. The camera never really got to get a good lock on the subject since it was moving. With moving subjects, when using AI Servo, it's best to get off 2 or more shots in bursts just to be sure that the camera gets a good lock on the subject. Like I said earlier, the first one shot is bound to be off in focus.

God I thought it was me at east someone else can't keep it still. I bought a new monopod with three legs on the bottom but with a big lens on it still shakes. I got them there jitters sonney.

I have the 75-300 IS and I can't believe the difference when I am trying to aim the camera and when I press the shutter-release half-way and the IS kicks in. I can't imagine trying to shoot handheld at 300 without IS.

And I can imagine it being difficult with a monopod, although there are things you can do to help when using the monopod -- don't just let the camera rest on it, actually exert downward force on the camera body like you're trying to drive the monopod into the floor. That extra force can help to stabilize the picture. Also, just as with handheld, hold your breath when framing and focusing the shot.

And maybe one or two cups less of espresso before a shoot can help, too!