|
The following is an excerpt from the
book "Dragonflies and Damselflies of Ohio", which I co-edited.
I also wrote the chapter on photography in that book.
|
|
More about
the book..
Odonata Images |
Photographing Odonata is challenging yet rewarding. Some of our Ohio Odonata
are arguably among the most beautiful insects in the world. Photographing these
fast-flying insects takes much of the same skill needed to capture them. The
following discussion is aimed at advanced amateur photographers with knowledge
of such things as focal length, depth-of-field, aperture, and shutter speed.
While large format equipment will produce exquisite images, portability is
the key to photographing Odonata. This argues for the use of 35mm equipment, and
there are basically two routes the photographer can take in regards to lenses.
The highest quality images will be taken with a macro lens at a relatively close
distance. This works fairly well for damselflies, but it is much more difficult
to approach dragonflies with such a setup. If a macro lens is used, a 90-100mm
lens is better than a 50 mm lens since the additional focal length will allow
the photographer to stay further away from the wary subject. Several camera
manufacturers market 180mm macro lenses that would be even better. A good macro
lens will focus to life size (1:1) without any additional accessories. Less
expensive lenses will have various extensions or screw-in lenses to reach 1:1
magnification; before purchasing one of these lenses consider your ability to
successfully screw in a finely threaded lens while balancing yourself in the
middle of a swamp and swatting mosquitoes!
For the dragonflies, less magnification is needed. A magnification ratio of
1:2 or even 1:3 is acceptable to fill a 35mm frame with the body and wings of a
medium-size dragonfly (1:2 means that the image on film is ½ the
"real" size of the image; 1:3 means the image is 1/3 life size). Thus,
for dragonflies, longer lenses such as prime or zoom lenses of 300-400 mm focal
lengths are ideal. The sharpest images will generally come from the more
expensive lenses. Speed of the lens is not as critical for photographing
dragonflies as it is for some other applications. In general, you will be
photographing on sunny days. Be aware that lenses slower than f 5.6 may
not autofocus correctly.
What about the camera? This is one case where cheaper may be better, since
there is some likelihood of dropping the camera into the water. Autofocus is
nice, but has problems with water, moving vegetation, and long lenses – all
factors one encounters when photographing Odonata. You probably can’t go wrong
with any of the entry-level autofocus cameras produced by the major
manufacturers such as Canon, Nikon and Pentax. Be sure that the model you choose
will allow you to mount the lenses you want to use, and that you can turn off
the autofocus and automatic exposure features and take pictures manually.
Another equipment option is flash. To get adequate depth-of-field, it is
often necessary to add light – even on a sunny day. Flash allows you to do
this, and modern cameras can add flash automatically. There are two basic
options. A ring flash is designed to fit around a macro lens and provide flash
at close distances. Shoe-mounted flash units will work at greater distances,
especially the distances involved when working with a zoom lens. A connecting
cord that allows you to remove the shoe flash from the camera is a very useful
accessory since it enables you to position the flash wherever you need it
(although if you remove the flash from the camera you will probably need to have
the camera on a tripod). Tripods themselves can be useful accessories. Mounting
the camera on a tripod will ensure sharper pictures, particularly when using
longer or slower lenses, or when shooting at 1:2 or 1:1 magnification ratios.
The tradeoff is the longer period of time it takes to compose a picture with the
camera mounted on a tripod, and the potential of scaring the subject away before
you get the photo!
Finally let’s consider film. Modern slide and print films are both of high
quality. For publication and presentations, slide films are the ideal. For
casual use, producing a scrapbook or a display, or scanning into a computer,
print film is preferred. In general, the slower the film (lower ASA or ISO
number), the higher the quality of the image. Faster films will have a grainier
image (although with modern films the quality is still very high). Higher speed
films allow you to increase depth-of-field and to increase
shutter speeds; this
means sharper images. Many photographers find 200-speed film an ideal
compromise. Those who look for higher image quality will gravitate towards
slower films (ISO 100 or 50) and compensate with tripods (to hold the camera
steady at slower shutter speeds) and/or flash. Those who prefer to get an image
at all costs will tend towards faster films (ISO 400 or 800) and take pictures
using daylight only. A new trend is the development of digital photography.
While digital photography has many advantages, including considerable cost
savings since film is eliminated, at the time of publication the quality of
affordable (<$2000) cameras was not comparable to 35mm film. This disparity
will no doubt change and at some point digital imaging will replace film.
Stalking Odonata to photograph them takes special patience and skill. Move
slowly. Observe the patterns of their movement and try to stake out a place near
a favorite perch. Remember that patrolling males in particular will return to a
given area over and over again. Get used to each individual. Often you will
discover its "comfort zone," the closest distance it will allow you to
approach. Sometimes repeated approaches to the same individual will habituate it
to your presence, and you will be able to approach closer on subsequent attempts
(other times this will simply scare or annoy the insect and it will fly over the
horizon). For many individuals, you will have to venture out into the water to
take the pictures. It is a good idea to scout the area out in advance without
the camera, lest you step into a hole or trip over a submerged obstacle.
Once in the vicinity of the quarry, it is time to compose the photograph. For
dragonflies, the most appealing shots are taken looking down on the back of the
specimen, showing the outspread wings. For this type of shot it is crucial that
the film plane (back) of the camera be on a plane parallel to the wings and the
body of the dragonfly. This is important since the depth-of-field will be very
small. You want the eyes, the wings, and the tip of the abdomen all to be in
sharp focus. Assuming you have aligned the camera parallel to the specimen, you
will probably need an f-stop of f16 of greater (f22, f32,
etc.) to get sufficient depth-of-
field. Your shutter speed should be at least 1/x,
where the x is equal to the focal length of the lens you are using, i.e.
1/250 of a second for a 200mm lens, 1/100 for a 100mm lens. If the camera’s
meter indicates that there is not enough light for a sufficiently fast shutter
speed, then you will either have to use a tripod (allowing for a slower shutter
speed), use faster film, or use flash. Other good poses for dragonflies are
lateral (looking at the side of the head, thorax, and abdomen) or frontal
(looking at the face). In either of these cases, it is vitally important to get
everything in sharp focus. On lateral shots the wings will be out of focus, and
on frontal shots the hindmost legs will be out of focus. In these situations it
is important to ensure that the critical elements – the eyes and the tip of
the abdomen – are in crisp focus. No photo will work if the eyes are out of
focus, and lateral shots are unsatisfactory if the tip of the abdomen is blurry.
Damselflies are somewhat easier to photograph. They don’t move as much, and
are more likely to perch. Most importantly, many species are tolerant of close
approach. Their small size argues for the use of a macro lens, and picture
quality will improve greatly if a tripod is used. The best pictures of
damselflies are lateral shots since the wings are held over the body. Again, one
must take care to ensure that the plane of the damselfly’s body is parallel to
the film in the camera so that both the eyes and the tip of the abdomen are in
focus.
In any photograph, composition extends beyond getting the critical parts in
focus. Ideally, the background will not distract the viewer from the subject,
and, needless to say, the foreground will not hide critical areas of the body.
Pay attention to the presence of distracting branches, discolored leaves, or
harsh shadows. In particular, shadows from the body falling on nearby vegetation
may be in good enough focus to be very distracting. Close-in vegetation can also
play havoc with flash. Any background that is noticeably brighter or darker that
the subject may throw off the camera’s meter. In such cases, you must make
some exposure compensation. If the background is very dark, let in less
light (by increasing the shutter speed or moving to a smaller aperture (larger f-number).
If the background is light-colored, let in more light than the camera recommends
by slowing the shutter speed or using a larger aperture (smaller f-number).
The reason for these adjustments is simple. A camera is designed to make
everything gray, and in trying to make a black background gray the camera will
let in too much light. Likewise, to make a white background gray the camera will
reduce the amount of light it exposes the film to. Camera meters vary in their
sensitivity to such background conditions, and some cameras have multiple meter
settings that further complicate things. Careful attention to the camera's
operating manual, along with some experimentation will help ensure accurate
exposures.
Even with the best equipment, careful technique, and considerable luck, it is
virtually impossible to get all of the critical features necessary for proper
specific identification on a single photograph. For instance, some structures
may be dorsal (on the back) and others ventral (on the belly)! You can
compensate to some extent by taking multiple pictures from different angles.
Even complete documentation, however, might not capture the characteristic some
future taxonomist might find necessary for definitive species identification.
Because of these difficulties, the Ohio Odonata Survey does not include
photographic records of species in its database. If you are uncertain as to the
identity of a specimen, you might want to capture it after taking its picture.