Birds in Flight lenses?

I have the 100-400, and its fantastic for airshows, but I must say even with the 1DMk2 that just got, it really sucks for birds in flight.
I shot 40 shots yesterday and only got about 3 keepers. I was shooting pigeons and seagulls.
True I may be the one that sucks at shooting them, but I thought with the great quick autofocus that the 1DMk2 has things would be improved over my 20D, not with this lens.
Anything or any ideas would be most welcome for this frustrated fuzzy bird shooter.
I know the 400 5.6 is probably better and also the 300with IS.
When using my trustey 70-200 without IS I get almost every shot perfect, even with BIF, but sometimes it just doesn't have the reach.
I am shooting all of this without tripod BTW.

I don't know the 1D II focus system but do you have it set to center focus and AI Servo?

i can't imagine a 100-400L not being able to get BIF shots of seagulls....unless it's you, maybe the lens needs to be checked out...

Bsmooth wrote in post #14308371
I have the 100-400, and its fantastic for airshows, but I must say even with the 1DMk2 that just got, it really sucks for birds in flight.
I shot 40 shots yesterday and only got about 3 keepers. I was shooting pigeons and seagulls.
True I may be the one that sucks at shooting them, but I thought with the great quick autofocus that the 1DMk2 has things would be improved over my 20D, not with this lens.
Anything or any ideas would be most welcome for this frustrated fuzzy bird shooter.
I know the 400 5.6 is probably better and also the 300with IS.
When using my trustey 70-200 without IS I get almost every shot perfect, even with BIF, but sometimes it just doesn't have the reach.
I am shooting all of this without tripod BTW.

something is wrong!

When I shoot seagulls with an XSi (450D) and Canon 100-400 the keeper rate is high - 90%

Immaculens wrote in post #14308390
I don't know the 1D II focus system but do you have it set to center focus and AI Servo?

That is correct on that body; center point only, AI Servo.

On that body, I can AF fast with a TC at f/8 with that lens.

Is it possible the OP is unconsciously altering the focus when zooming/holding the lens .
Seen lots of great shots of birds with this lens , Watt100 springs to mind .

Airshows <> BIF

Any camera can do cars/planes as target is much bigger and easier to predict in AI servo mode. I would say practice. Make sure:

1. IS off
2. Focus limiter in the farthest setting
3. High enough ISO even in day time to get higer ss, like 1/2000
4. Acquire target by holding * button. Track and when ready start pressings hutter wjile keeping * button pressed. This assumes C. Fn 4 = 3
5. You can try using surrounding points to center in AF assist. Forgot what C. Fn does that.

Yep went through that list except IS is on focus limiter actually is better at close setting, farther had even worse problems, and it wasn't shutter speed the problem, the focus just didn't happen on the birds, focus button was on and was using center focus with AI tracking on. Also had zoom locked at 375.
Sample attached

HTTP response: NOT FOUND | MIME changed to 'image/gif' | Redirected to error image by FLICKR

Bsmooth wrote in post #14309872
Yep went through that list except IS is on focus limiter actually is better at close setting, farther had even worse problems, and it wasn't shutter speed the problem, the focus just didn't happen on the birds, focus button was on and was using center focus with AI tracking on. Also had zoom locked at 375.
Sample attached

I can't read the EXIF data but it's definitely looks out of focus .. so to isolate the problem it's either your camera or lens.
(I know, that doesn't help much!)

watt100 wrote in post #14309923
I can't read the EXIF data but it's definitely looks out of focus .. so to isolate the problem it's either your camera or lens.
(I know, that doesn't help much!)

Or the operator. If you had no keepers, I would suspect the lens, but since you had 3, I think your technique could be suspect. The image you posted has the exif data stripped so it's not any help identifying the problem.

Could you post an image with exif data intact? BTW, are you turning IS off? With the shutter speed required to capture birds in flight, it's not necessary and could be slowing down your AF.

i disagree with IS off, as it stabilizes the view finder, and makes tracking easier in my opinion....if you're hosting on flickr, can you post a link to the page, and the exif should be visible from there...

DreDaze wrote in post #14310238
i disagree with IS off, as it stabilizes the view finder, and makes tracking easier in my opinion....if you're hosting on flickr, can you post a link to the page, and the exif should be visible from there...

Yep - I like IS at almost any focal length I have - especially over 180mm
its like a technological gift...

That sample posted is focused off into the clouds.

On a normal day it's very hard to believe a 1DMkII + 100-400L would give low BIF keeper rate. The sample image shows the subject is rather small in the frame. That means, harder to place your center AF point on the bird constantly while handholding and panning. If situation allows, zoom in all the way to 400mm so that there's a larger subject area your camera's center AF can grab. Not sure if this setting is available in 1DMkII but in MkIII it allows user to set the AI Servo Tracking less sensitive so that the camera won't switch focus immediately when the subject escapes the focus point.
Another suggestion, for sky background like this, you can actually use ALL AF points and let the camera pick out the bird with whichever AF points it thinks are appropriate. You might see the keeper rate improves significantly. Sky bg is

1dmk2 has servo sensitivity but for something like this example shot, normal sensitivity is fine. I would have used more points or like all points as mentioned above. I have my home button programmed to track with all points in AI servo mode.