Birds... Fast Birds... Focus Help Needed w/7D 70-200 f2.8 USM IS II

TimR32225 wrote:

There is some good info in this thread but respectfully, there is also a lot of bad info.

The OP is using a 70-200 f2.8 lens. EVEN at 200 mm (which is way too short for most bird photography) you have adequate depth of field at f4 and certainly at f 5.6 to capture the entire body of a seagull at 30ft. Anyone who doubts that should check their depth of field calculator.

So any aperture smaller than f4 or certainly f5.6, is purely a waste of shutter speed, which makes it more likely that you miss the shot due to motion blur.

Trying to use a single focus point on a bird as small as a seagull is the wrong approach for 2 reasons: (1) it's difficult to follow a relatively small bird with only 1 focus point (you will frustrate yourself), and (2) there is NO need to only use one focus point because any part of the bird you focus on will render the entire bird in focus with the depth of field you will have at 200mm f5.6, unless the bird flies very close to you.

It would be better to use either zone, or single point with surrounding points active. If you use all 19 points, the focus will be slower, and there is more chance of error. You would only want to consider using single point on a very large bird when you cannot use settings that keep the entire bird within the depth of field. And then you would need to try to keep the focus point on the bird's head.

Use the focus limit switch set to the furthest setting, as this will result in a lot quicker and more responsive focus lock. Also, if you lose focus on the bird, the camera will reacquire focus a lot quicker because it is hunting a narrower distance range.

The suggestion to shoot at +1 EV for a bird in front of a bright background... is correct. It will be usually be anywhere between +2/3 and + 1 1/3, depending on the brightness of the sky. This will prevent you getting a dark silhouette instead of the result you want. But better to meter off the sky and shoot at +1EV in manual mode instead of Av or Tv. That way if the brightness of the background changes, you still get a good exposure because the exposure will not be affected by a changing backround in manual exposure mode.

The smaller (and faster) the bird, the more difficult the shot. Seagulls are fairly slow and relatively easy. Smaller birds are more difficult. This Great egret below, was a piece of cake. It's probably 5x the size of a seagull, and flies slower. The aperture used on this shot (f6.3) provided a deep enough depth of field to render the entire bird in focus, and this guy is way bigger than the largest seagull. So you don't need f16 or f11 or even f8. Settings like that are a overkill and total waste that actually diminish your chances of getting a decent photo. Using f5.6 should be a small as you need to go on aperture, unless the bird is very large or flies very close. When the situation permits, I always plan my shots and check a depth of field calculator if I'm not sure. All you need to know to plan ahead, is the expected distance to the subject, and the relative size of the subject.

Most important thing of all is have fun and enjoy what you see. Getting the shot is icing on the cake.

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Photoblog at: http://timrucciphotography.blogspot.com/
Gallery at: http://www.timrucci.com
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