How to focus on a large flock of birds

[E Rogers]

Looking for some suggestions on how to focus on a large flock of birds (sandhill cranes). Do I try to catch an eye on one while flying or just do wide area auto focus without eye detection and l;et the camera pick the focus spot. I realize that will most likely pick the closest object which may be OK. Any experience with this one? Thanks.

 

[Cameron T]

It depends on a lot of factors and the shot you want, along with the DOF you'll have at any given settings. I'd say just pick what you want in focus, put a point there, and shoot. You're probably not getting the whole flock in perfect focus regardless.

 

[DRwyoming]

Looking for some suggestions on how to focus on a large flock of birds (sandhill cranes). Do I try to catch an eye on one while flying or just do wide area auto focus without eye detection and l;et the camera pick the focus spot. I realize that will most likely pick the closest object which may be OK. Any experience with this one? Thanks.

Honestly if there are many birds filling the frame it almost doesn't matter what focus mode you use as long as it focuses on at least one bird. Other birds at or very close to that distance will be sharp and others further back or forward will be less sharp. You can stop down aperture a bit to extend the depth of field(DoF) and perhaps get more in decent focus but there's no focus mode that will get all of them in focus for a large flock with birds at different distances especially when shooting long focal length lenses where DoF will be shallow. In a situation with many birds in the frame I'll tend to use a Wide Area, small or large in a mirrorless camera or Group or a mid sized Dynamic focus area in a DSLR.

Here's an example of the kind of image where choice of focus mode really isn't that critical. This was an older shot with a DSLR but results would be pretty similar with a mirrorless camera and a small to mid sized AF area:

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If it's just a few cranes then yeah, pick a focus mode that gets the most visually important bird in good focus, ideally on its eye, but again birds closer or further from your position will tend to fall out of focus when shooting with long lenses at wide apertures. Again, stopping down aperture a bit can help extend the DoF and get some of the other birds sharper. For small groups flying in formation I'll tend to use Wide-Small with bird subject detection in a mirrorless camera and something like Group in a DSLR with the focus area over the primary bird I want sharp.

Here's an example of a smaller group. In this case I was in Wide-Small with subject detection enabled and tracking the lead pelican, stopped down a bit for some extra DoF and timing for when they banked and their distances to my position were similar:

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[Whiskeyman]

If you can, pick one bird as your subject, compose and shoot.

 

[ajrmd]

Much of the advice provided has been sound. If one is shooting a large flock of birds flying, then assuming an adequate DOF, it doesn't matter what subject one focuses on. If it is a smaller group of birds perched, wading, etc., the general rule of thumb is to focus on the more proximate bunch. Of course, rules are meant to be broken, and I remember shooting a flock of swimming waterfowl and what made it interesting was the aberrant, lone different species in amongst all of the others. Naturally, that was the subject of interest, consequently the AF was on him.