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Pro Secrets:
Using Live View for Nature Photography
by
Ian Plant
In the
old days of large format photography, something
magical happened when one stuck their head under a
dark cloth—the
photographer was able to see a "live view" of the
scene, projected by
the
lens onto the camera's huge 8"x10" or 4"x5" ground
glass. Compared to peering through a dark 35mm
viewfinder, a ground glass projection is a stunning
sight to see. Now, in the age of digital, live view
has returned, albeit with an electronic twist. While
a typical digital camera LCD screen isn't quite as
big as a large format camera ground glass, one can
now see a live view of their scene in bright, vivid,
and rich full color.
Live View
has become a vital part of my image capture
process, and I use it for almost every photograph I
make to optimize focus,
composition, depth-of-field, and even
exposure. In my opinion, Live View has the potential
to revolutionize nature photography, and hopefully
the technology will continue to evolve and improve
over time.
I
recently wrote an article for the November 2009 issue of
Popular Photography Magazine,
about incorporating Live View into one's nature photography
workflow. Since the article is available only in the
print issue and not online, I thought I'd publish a
companion article here that would expand on some of the
concepts and themes I discussed in the magazine.
Fellow photographer
Joseph Rossbach using Live View in the field to
properly compose, focus, and expose an image.
Hogcamp
Branch, Shenandoah National Park, Virginia.
How Live View
Works
In
most DSLR camera systems, Live View is generated by
flipping up the camera's mirror—which
normally projects light into the camera's viewfinder—and
continuously and directly projecting the image
formed by the lens onto the digital sensor, which in
turn feeds the LCD screen with the live preview
image. As a result, when using Live View, you cannot
see through the viewfinder—nor,
for that matter, use the camera's normal autofocus
system.
Most compact consumer cameras don't have a
viewfinder or a mirror, and they are able to
continuously project a Live View image.
A few DSLR models
actually have two sensors—one
dedicated to image capture and another to the live
view preview—allowing simultaneous use of the
camera's viewfinder and Live View LCD preview
screen.
How your camera creates a Live View preview may affect
what you can and cannot do using Live View.
It is worth noting
that
not all DSLR Live View systems are created equal—some
are more fully featured than others.
For example, my Canon
5D Mark II camera has one of the most feature-packed
Live View systems on the market, allowing me to do
everything that I discuss in the article below. Even if your Live
View system can’t do everything mine can, it
will still be able to do quite a bit to help you
improve your nature photography images.
Live
View can be very useful when dealing with tricky
focusing and light.
Great
Smoky Mountains National Park, North Carolina.
Find Perfect Focus,
Every Time
Live View makes getting perfect focus much easier
than peering through a tiny, dark viewfinder. Live View allows you to focus using your
camera’s large, bright LCD screen. Even better, most
Live View systems allow you to zoom
in as much as 100% to make sure that your focus is perfect.
This can be particularly important when working with
macro subjects; even being slightly off in your
focusing can ruin the final image.
Live View is also very useful in low light, when
viewfinders can sometimes be too dark for accurate
focusing. Live View will compensate for low light by
brightening the LCD display (typically this
brightening feature can be turned on and off using
your camera’s menu settings); the ability to zoom in
on a relatively bright element of the scene
is also helpful when focusing using Live View in low
light. Since autofocus typically doesn't work in
Live View, I always use manual focus when using Live
View (some Live View systems incorporate a special
autofocus system that works specifically through
Live View, separate from the camera's regular
autofocus system, but since it is so easy to
accurately manually focus in Live View, you probably
won't need it).
Where Live View really shines is when you are
composing "near-far" landscape images, and you need
as much depth-of-field as possible.
Depth-of-field is the portion of a scene that
appears acceptably sharp in an image. Although a
lens can precisely focus at only one distance, the
decrease in sharpness is gradual on each side of the
focused distance, so that within the depth-of-field,
the image appears acceptably sharp. Depth-of-field
is controlled by aperture selection—a
wide aperture (for example, f/2.8) has a very narrow
depth-of-field, whereas a small aperture (for
example, f/22) has considerable depth-of-field,
likely rendering most or all of the image as
acceptably sharp.
Landscape shooters are always struggling to find the
hyperfocal point, which
is essentially the
point of optimum focus in an image which maximizes
depth-of-field. The concept of hyperfocal distance
is an easy one: if you focus a lens at the correct
point, and select the correct aperture, everything
in the photograph from the nearest element to the
farthest will appear sharp. Typically, the
hyperfocal point and corresponding aperture would be
calculated using a lens' depth-of-field scale (which
you don't see much of these days); using complex
charts and measurement; or, most commonly, by
guessing the right focus point and overcompensating
by selecting a very small aperture to ensure maximum
depth-of-field.
An
example of a hyperfocal point. The hyperfocal
distance will vary depending on relative positioning
of near and far
elements in a scene, and the focal length used. The
aperture necessary to get sufficient depth-of-field
will also vary.
Vermillion Cliffs National Monument, Arizona.
This last method,
although it worked reasonably well in the past, had
two significant problems. First, guesses were often
wrong, leaving critical elements of the image with
less than optimum sharpness. Second, use of very
small apertures such as f/22 leads to a phenomenon
known as diffraction, which results in an
overall decrease in image quality. Most lenses are
designed to be at their sharpest between f/8 and
f/11, so it is important to avoid smaller apertures
like f/16 and f/22, if possible. Of course, if you
need the extra depth-of-field, use the smaller
apertures—it
is better for the image to suffer a small amount of
softness because of diffraction, than to have
important elements of the scene out of focus.
The ability to zoom and pan around an image in Live
View really helps when you are trying to find the
correct hyperfocal point to balance
focus between near and far elements in a scene.
Here's how: zoomed in to 100%, focus first on the
object in the scene closest to you. Then pan to the
object in the scene farthest from you, and focus
there. Now, try to find a focus point right in the
middle of these two—or, put another way, find a
focus point that renders both the near and far
objects equally out of focus. This, roughly, will be
your hyperfocal point, the point in your scene that
maximizes your depth-of-field from near to far. Now,
stop your aperture down, depending on how much
depth-of-field that you need. For many shots, f/11
might be sufficient; for scenes that go from very
near to the horizon, f/16 or f/22 may be necessary.
Some lucky
Canon users can take this a
step further: many Canon cameras allow the user to
preview depth-of-field in Live View, using the
depth-of-field preview button found on the front of
the camera near the lens. When you press the
depth-of-field preview button, the lens will be
stopped down to your selected aperture, and the Live
View image will get dark for a moment (because the
smaller aperture lets in less light), but then Live
View will compensate and brighten the image. When
using Live View in conjunction with the
depth-of-field preview button, you can actually see how your chosen aperture affects
apparent sharpness and depth-of-field throughout the image,
allowing you to make
focus and aperture adjustments until you find the
perfect combination. By using this feature on my
Canon camera, I am able to avoid diffraction-causing
apertures unless I really need to use them.
When
you need critical focus from near to far, Live View
can help you optimize depth-of-field.
One
final note: for those who use mirror lock-up to
minimize vibrations, when using Live View you can
turn this feature off. Remember, when in Live View
(on most cameras), your mirror is already in the
raised position. So, feel free to trigger the
shutter directly from Live View for vibration-free
images.
Use Live
View as a Compositional Aid
Live View allows you to assess
composition at a larger scale than you can see using
your DSLR viewfinder. Furthermore, Live View
gives you a 100% view of your composition, something
that most DSLR viewfinders cannot do. Many Live View
systems also give you the option of a grid overlay (found in your menu settings), which can help when
making rule-of-thirds compositions, and to ensure
that horizon lines are level. You’ll find Live View
indispensible when dealing with odd-angle or
low-level shots that make it impossible to get your
eye to the viewfinder.
Live
View also allows you to watch in real time as a scene
unfolds, permitting you to trigger the shutter at
precisely the right moment. I find Live View
particularly useful when trying to photograph
flowers in the wind. I use Live View, zoomed in on a
flower at 100%, to comfortably watch and wait for
the flower to stop shaking. I find this method much
more accurate than simply looking at the flower from
even a short distance away, as the flower may appear
still to the eye, whereas 100% Live View will reveal
that it is actually still slightly moving.
Live
View can help you capture the perfect moment, when
everything in the scene is to your satisfaction.
Use Live
View to Ensure Proper Exposure
Most Live View systems allow you to preview exposure
and white balance changes on your LCD before you
take the shot. Some Live View systems even show you
a preview of your histogram, using what is
known as exposure simulation. These tools
can assist you in determining proper exposure and
white balance settings before you take an image, so you don’t have to waste
time taking test shots to make sure you've got things
right—which can be especially useful when working in
fast-changing lighting situations. On my various
Canon cameras, I find that exposure simulation is
reasonably accurate, but not always entirely so. For
example, sometimes the simulated histogram will show
that my highlights are safely below the clipping
point, but the final image will show highlight
clipping. Accordingly, I often reduce exposure a
small amount below what appears to be optimum in the
preview histogram. Even though exposure simulation
doesn't always work perfectly, it does significantly
reduce the number of images with clipped highlights
or shadows.
Conclusion
Live View is much more than a bell-and-whistle
gimmick—it is a serious professional tool that can
help you significantly improve your nature
photography images. Live View should become a
standard part of your nature photography image
capture process.
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Essential Tips for
Taking Great Landscape Photos
Ian Plant
Chasing the Light
is a 62 page downloadable PDF eBook filled with informative text,
stunning full-color images, and plenty of insights and inspiration,
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