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If you've looked around my website
photo galleries, you've no doubt noted that I shoot a lot of birds in
flight. Not only are these images very saleable for my business, I just
plain love doing it. It is addictive!
It
is also not an easy thing to do. There are things you can do, however,
to increase your success rate.
First
and foremost, birds in flight are very, very difficult to capture
against a complex background. Because you must rely upon your autofocus
on these speed demons -- and your autofocus can just as easily lock onto
the complex background rather than the bird -- you will always get
better results if you can photograph the bird against a simple
background. Obviously, a cloudless sky yields the best results, followed
by a solidly cloudy sky, and then water -- in that order. When you view
an image of birds flying against a complex background -- such as ducks
flying down a shoreline with trees in the background -- give the
photographer a "thumbs up" because now you know that those
images are by far the most difficult to produce!
Second,
keep your shutter speed as fast as possible. While I've gotten nice
results at 250th of a second, that is about the bottom end for sharp
flight photos. But most of those were accidental! I prefer to keep my
shutter speed at at least 500th of a second, and faster is even better.
Ideally, I try to get 1/1000th of a second.
Third,
when shooting against sky (even cloudy skies) or water, you must open up
your exposure by at least 1/3rd of a stop, and on many occasions, up to
a full stop. The reason is simple. Unless the bird fills the frame, the
camera will try to balance the exposure to insure that the sky (water,
etc.) is properly exposed. But you don't want a nicely exposed sky! You
want a nicely exposed bird. You must compensate by opening your
exposure. And believe it or not, the cloudier, darker the day, the MORE
you need to open the exposure. Don't ask me why. I haven't a clue. But
I've found that if I must shoot on a dark, overcast day (and I try not
to), I need to open it up a full f-stop to get any "light" on
the bird.
Balancing
this exposure of background and bird presents a problem when you're
shooting at a place where one moment, the birds are up against the sky,
and the next moment, drop down against a dark background -- again, the
ducks flying down a lake shore situation would be a good example where
one second they could be against trees, and the next, above them. With
your exposure opened up for "sky" photos, your
"background" photos will be over-exposed. With your exposure
set for "background" photos, "sky" photos will be
too dark. There's really not much you can do about this if the action is
happening quickly. In this situation, I'll often set my "sky"
exposure compensation a little lower than I might otherwise -- for
instance, 1/3rd of a stop instead of 2/3rds. This will yield slightly
dark "sky" photos, and slightly bright "background"
photos -- both of which will be within the capabilities of Photoshop to
correct.
Generally,
I use just the center autofocus point. You want to control what the
camera focuses on, not let it make the decision. When you set your
autofocus to multiple focal points, you could just as easily get a
really nice photo of the cloud behind the bird, not the bird, since the
camera will lock onto whatever gives it the best contrast. The exception
to this is when you're shooting against a virtually blank background. At
times like this, setting your focus to use multiple focal points will
increase the number of sharp shots.
So
what's the best lens, or at least focal length, for wing-shooting?
Others may have come up with a different conclusion, but in my
experience, a lens with a focal length of no more than 400mm is best.
Once I get beyond that focal length, several things happen that decrease
the number of usable images. First, the depth of field decreases as
focal length increases (there are work-arounds, such as increasing your
aperture), which means that the area of acceptable sharpness (front to
back) is smaller, and thus, fewer sharp images.
Second,
lenses with longer focal lengths are generally bigger and
heavier. Since flight shots -- at least on smaller, faster moving birds
-- requires mobility, and thus, hand-holding, these heavy, big lenses
are wearisome to hold. They also have an inertia of their own. By that I
mean that once you start swinging 8 pounds of 500mm lens, and the bird
takes a dip or rises, it is harder to match that movement with the
lens. It doesn't want to move, because its inertia is directing it
elsewhere.
Third,
I've found that once I get over 500mm, not only is the lens magnifying
the bird, it is also magnifying every little error I make. Even with
Image Stabilization, at these extreme focal lengths, camera shake
becomes a problem, and the longer lens makes sure that not only does it
do a great job of magnifying the bird, but also every little shake,
rattle and roll. Can't be helped. If you have nerves of steel, are built
like a pro-football player, you may get different results.
So
why not use a tripod on these big lenses? You can, especially if you
have a Wimberly-type mount. That said, there are few places where you
have the time and luxury of setting up such a system, at least on the
kind of subjects I shoot. And even with such a system, you will miss
many shots because as good as this system is, you can't really keep
apace with truly fast moving, or erratically moving, birds. On cranes,
pelicans, geese, eagles, etc. -- big, slow moving, birds -- this system
works well.
Although
I've not tried a gun-stock type of mount for flight shots, I suspect
they would work well. (UPDATE -- I NOW HAVE USED THE BUSHHAWK SHOULDER
MOUNT AND LOVE IT -- READ THE REVIEW HERE.) Most of the time, I use my 100-400 and just hand
hold it. At times, I will mount this or other lens on my monopod, which
has a pivoting head, so that I can swing the collapsed monopod up under
my armpit. I clamp the monopod between my arm and side, which increases
stability and works much like the commercial gunstock mounts. I have, on
occasion, also just stuck the monopod against my thigh or into my belt.
However, any of these combinations does decrease your ability to move
with the bird. The sad fact is that whatever means you devise to
increase steadiness is likely to decrease your ability to move quickly
with the bird.
Everything
in this type of photography is a trade-off! I wish for a longer focal
length many days, but know that I generally get crappy results once over
400mm. I wish for a steadier system, but know that tripods and other
devices only decrease my mobility, or my ability to track a bird in
flight. I wish for lenses with faster apertures, but know that those
faster apertures come with a big weight and size disadvantage.
Which
is why I'm thankful we've moved into the digital age. Yes, there have
been remarkable photographers that produced spectacular flight shots in
the days of film. But one thing I've learned is that getting exceptional
flight shots requires taking a lot of images. A great many will be
throw-aways. It can be done with film, but you'd break the bank! And
digital also offers the advantage of multiple ISO values -- by raising
your ISO you can increase your shutter speed, and high shutter speeds
are critical.
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