7D, focusing and concert shooting.

[New Hobby]

I've been playing around with the 7D at very low light concerts. Right now I have been able to get the focus keeper rate up but wanted to see what other folks where doing to increase the focus keeper rate. I'm shooting at about f/1.6 so focus is very important.

I've been using the AI focus, single focal point, multi shot. I have found using the "bumping the focus" technique from BiF photography has been very helpful. This is where one get the focus and then resets the focus just before taking the shot. Here is a longer explanation. http://www.birdphotographers.net/forums/showthread.php?t=1949

I have not played too much with the focus setting on the camera except AI servo tracking sensitivity bumping it up one. I think this has been helpful but it's too early to call. Also have the AI servo 1st/2nd img priority set to 0:AF priority/Tracking priority.
Any thoughts on these setting?
Any others folks have found useful?

[CosmoKid]

the only thing i can offer up is that AI Focus seems to be a mode no one uses. i would stick with single shot or servo.

[New Hobby]

the only thing i can offer up is that AI Focus seems to be a mode no one uses. i would stick with single shot or servo.

I tried the servo with the 40D and the issue was using flash. The shutter / flash would trigger before focus was achieved. This only happened with the flash. I have not tried it with the 7D yet but I will.

[bacchanal]

I tried the servo with the 40D and the issue was using flash. The shutter / flash would trigger before focus was achieved. This only happened with the flash. I have not tried it with the 7D yet but I will.

In Servo mode, the camera uses a shutter priority...the shutter will trigger whether the image is in focus or not. From what you've said, it seems like you may be able to change that on the 7D, but I'm not sure. The flash focus assist beam will not work in Servo mode.

In One Shot mode, the camera uses a focus priority...the shutter will not trigger unless the camera thinks that the image is in focus.

AI Focus mode simply switches between Sevro and One Shot depending on whether or not the camera detects a moving subject.

[joove]

^^ Even if you set the Ai Servo 1st/second to AF-Priority/Tracking ? Shouldn't that set AI Servo to also use focus priority ? (Even if you do not get the focus confirmation beep) ?

[bacchanal]

^^ Even if you set the Ai Servo 1st/second to AF-Priority/Tracking ? Shouldn't that set AI Servo to also use focus priority ? (Even if you do not get the focus confirmation beep) ?

Yeah, you're right...so that should prevent the issue he was having with the 40D.

[New Hobby]

^^ Even if you set the Ai Servo 1st/second to AF-Priority/Tracking ? Shouldn't that set AI Servo to also use focus priority ? (Even if you do not get the focus confirmation beep) ?

Tried it last night. Same as the 40D so I'm thinking AI Servo and Servo are mostly useless with flash.

[Coppatop85]

Hey New Hobby, which focus mode/points do you use? I have a 7D on the way, should be here by the 1st. I am very excited, but I don't have any experience with a focus system of this type.

I have used the XTi, and 40D, so the 7D is a completely different animal. On the 40D I normally use the center point, or another single point (using the joystick to select), but these expansion AF point zones are interesting. This will most likely be the last APS-C body I buy, but I'm sure it will last me many years. Hopefully I can afford a second, full frame or APS-H body in the future.

[New Hobby]

Hey New Hobby, which focus mode/points do you use? I have a 7D on the way, should be here by the 1st. I am very excited, but I don't have any experience with a focus system of this type.

I have used the XTi, and 40D, so the 7D is a completely different animal. On the 40D I normally use the center point, or another single point (using the joystick to select), but these expansion AF point zones are interesting. This will most likely be the last APS-C body I buy, but I'm sure it will last me many years. Hopefully I can afford a second, full frame or APS-H body in the future.

I'm now using single shot and single focal point. Works well.

[andrewq]

Tonight I'm going to go for AI Servo, single point expansion, slow AI servo tracking and something else I can't remember. All this through a 17-50mm f/2.8. We'll see.

Oh, question for you: How do you get away with using flash at a gig? In my world that is one of the cardinal sins.

[totoyo]

Hi, the "bumping focus technique" has no sense on 7D because the AF tracking in AIservo is predictive in this camera model, the manual says to beguin the tracking object at least two seconds before taking the photo to allow the AF algorithm to predict the next position of the object.