Canon EF 100-400mm f/4.5-5.6L IS USM - AKA The Dust Pump

I shoot a lot of football, baseball, golf and other outdoor sports. I use a monopod while in the sitting position all the time because it easier to control and after three or four hours of holding several pounds your arms do get tired.

Tom Reichner wrote in post #18314183
When shooting outdoor team sports, aren't we usually lying on the ground, or sitting on the ground - in order to get the best angle?

Be my guest! Especially if you're shooting freelance for Sports Illustrated, sure! But even then, if you're a pro, you're probably using two bodies, one with a 70-200 f/2.8 and a 400 f/2.8 in order to catch the entire field. I don't have $30K for that, so I use The Dust Pump on one body.

Glad to know that works!

You're right.

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I shoot youth sports, often several games in a row (and up to 10 in a day). I sit on a stool or sometimes a cushion to get a better angle. I've never been able to sit comfortably with my legs crossed.

I've tried a monopod a few times but am much more comfortable hand holding. Makes for a long day. Maybe I'll get better at it with softball/baseball this Spring.

Anna's Hummingbird

Dust pump still going strong.

Girls Varsity Soccer from a week ago. Enjoy!

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Please forgive and move if this is the wrong thread to post a dust pump technical question.

Short version: my 100-400 I has stopped being able to acquire focus if I change the focus distance btw shots. Originally, it was a only a sporadic problem, increasing frequency gradually, & now it's a constant problem. From 100-275 mm, changing distances results in slow focus, but it will acquire focus. From 300-400 it's a no go. I shoot in full manual mode on a Canon 60d.

Other relevant info: this problem happens in M mode; the work-around is to rotate to full Auto, the lens focuses here. Flipping back to manual, without changing anything else, the camera/lens will continue to focus as long as the subject is within a few short feet of where auto-focus in auto mode was achieved. As soon as I try to focus beyond a small radius of that point, the problem & work-around repeat. As I said, this only happens at the longer distances of this zoom, and its gone from sporadic to continual. (I usually use the center focus point; however, changing focus points doesn't affect the outcome.)

Would gratefully accept user error, just know until 6 mos ago this combo focused very well.

Thoughts?

This thread has been needing a little love...

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That's a great one!

Two different kind of birds from the front porch today.