The beginner must not suppose that good bird photographs can be made
only with expensive apparatus. Under favorable conditions there is no
great difference in the results secured with the ordinary camera and
lens of any reputable maker and those of the highest class. My own work
has for the greater part been done with an outfit costing about thirty
dollars; and although the best lens is, of course, to be desired it is
not a necessity, and cost therefore is no more an obstacle to the
hunting of birds with a camera than it is to their pursuit with a gun.
_The Camera._—Individual taste will doubtless govern the size of the
camera chosen, but most naturalists and sportsmen consider the camera
carrying a plate four by five inches as the one best adapted to their
wants, and with this decision I heartily agree. The advantages of size,
weight, and economy, both as regards the camera, its holders, and
plates, are all in favor of the 4 × 5, while as far as the bird
photographer is concerned, it is not often that he has need of anything
larger. The image of a bird will rarely be without adequate setting in a
space four by five inches, which will also be found to be large enough
for the portrayal of nests and eggs.
The 4 × 5 also reduces proportionately in making lantern slides, and if
the picture is made the long way of the plate—that is, higher than
broad—it can be easily adapted for illustrative purposes in duodecimo or
octavo books. When a larger picture is desired it can readily be made by
enlargement, an increase in size of three diameters, or six times the
area, being possible from a sharp negative without undue loss of
definition.
For use from a tripod any one of the several excellent long-focus
cameras now on the market will be found to answer every requirement. If
it is proposed to employ a telephoto lens, care should be taken to
select the camera combining greatest bellows length with rigidity. A
reversible back increases the size somewhat but adds to the length of
bellows, and will be found serviceable in the many awkward situations in
which the bird photographer is often placed by the nature of his
subjects.
The Kearton brothers have an “adjustable miniature” on the top of their
camera, which they state “is used as a sort of view finder when making
studies of flying birds. When fixed in position and its focus has been
set exactly like its working companion beneath it, both are racked out
in the same ratio by the screw dominating the larger apparatus.”[A] The
purposes of this attachment, however, will, it seems probable, be better
served by the reflecting camera described below, while as a finder alone
its place may be taken by the “iconoscope” and other of the prism
finders, the brilliant image cast by which is such a striking and
satisfactory improvement on the hazy outlines given by the average
so-called “finder.”
Footnote A:
From Wild Life at Home, how to Study and Photograph It, by R. Kearton,
illustrated by C. Kearton; a work of the utmost interest to the animal
photographer, who should also read With Nature and a Camera, by the
same authors (Cassell & Co.).
For use as a hand-box only two kinds of camera are available, for it
must be borne in mind that the set-focus or short-focus, wide angle
“snap-shot” cameras, so popular among the button-pressing fraternity,
are not adapted to the wants of the bird photographer, who must
therefore avail himself of either a twin-lens or a reflecting camera.
Twin-lens cameras are manufactured by several well-known firms, but the
trade size is of too short focus to be desirable. In this type of camera
two lenses of equal foci are employed. They are set one above the other
in bellows, which move as one. The lower lens makes the picture, the
upper projects a duplicate of the image cast by the lower lens to a
mirror set at an angle of forty-five degrees to the plane of the plate,
whence it is reflected upward to a ground glass, which is protected by a
hood, on top of the camera.
To focus perfectly the lenses should be “matched” or “paired”—in short,
interchangeable—thereby greatly increasing the cost of the camera, which
is also rendered objectionable by its large size.
The reflecting camera possesses all the advantages of the twin-lens, but
requires only one lens, and when in use is not materially larger than
the ordinary 4 × 5 long-focus box.
The reflecting camera now in my possession was designed and made by John
Rowley, of the American Museum of Natural History, and was fully
described and illustrated by him in Bird-Lore for April, 1900. It
resembles the upper half of the twin-lens camera in that a mirror, set
at an angle of forty-five degrees to the plate, is interposed between
the latter and the lens, and reflects its image to a ground glass on top
of the camera. This mirror, however, is movable, and the desired object
appearing in focus on the ground glass, a lever is pressed downward
which raises the mirror to the top of the box, where it automatically
releases a focal-plane shutter (see beyond, under The Shutter) directly
in front of the plate, when the image-bearing rays, before intercepted
and reflected by the mirror, are registered on the plate, from which the
slide had previously been drawn.
When the focal-plane or curtain shutter has been set and the slide drawn
from the plate holder, this camera is like a cocked gun, which may be
fired the moment it is sighted; or, in other words, the exposure may be
made the instant focus is secured. With this camera one may take
advantage of any offering opportunity to secure a picture of a bird or
beast when afield, and this fact, by increasing the possibilities of an
outing, adds greatly to its pleasure.
Mr. Rowley has so designed this camera that it may be used from a tripod
as well as in the hands; but when the tripod camera is to be left,
perhaps for hours, hidden near some bird’s nest, I prefer to employ the
long-focus for this purpose, and retain the reflecting camera for
possible use on the birds that so often approach closely when one is in
hiding. The advantages possessed by this camera are so apparent that it
doubtless will soon be placed on the market.
_The Lens._—Professional photographers differ so widely in their
opinions of the relative qualities of the various makes of lenses now on
the market, that I approach this subject with diffidence, and, without
presuming to offer advice, present the results of my experience both as
to lenses and the requirements of the bird photographer. In regard to
the latter phase of the much-discussed question of “What lens shall I
use?” I may speak with more confidence. For nests with eggs or young
birds—subjects which may be approached closely—a six- to
eight-inch-focus lens forms a large enough image, and at the same time
gives depth of focus and sharpness of definition without the use of the
smaller diaphragms. In photographing birds, however, it is generally
difficult to get within “shooting” distance, and at least a fourteen- to
sixteen-inch lens is needed in order to secure an image of sufficient
size. Depth of focus is here, in my opinion, not desirable, and the
focal point—the bird—is brought out more clearly by the fusion of all
the objects back of it into a uniform background.
When a bird, either young or old, is the subject, great speed may be
required, and sometimes under light conditions which severely test the
qualities of the lens. To fully meet these demands of distance and time
two lenses would be needed; but, aside from the increased cost and the
inconvenience of using two lenses, the great size and weight of a
long-focus lens are drawbacks. These objections are largely overcome by
the use of the symmetrical lenses placed in most of the long-focus
boxes, or, if expense be not considered, by a “convertible” lens.
For several years I have used a “Victor” lens, sold with the “Premo”
long-focus camera. The combined focus of the front and back lenses is
seven and a half inches, of either of the lenses alone, fifteen inches.
The single lens therefore, the distance being the same, gives an image
double the size of that cast by the two lenses together.
This lens has been thoroughly tested, and many of the pictures given in
this book were made with it. When the conditions are favorable and the
subject not extremely difficult it yields satisfactory results.
The “convertible” lenses of various makers are also separable, and where
the rear and front lenses are of different foci three focal lengths are
obtainable. These lenses are of the highest grade, and consequently
expensive. In a bright light, or where great speed is not required, they
do not seem to be as superior to the trade lens as the much higher price
would lead one to expect. But in dull days, or in the shadow, or where
extremely rapid exposures are necessary, their superior qualities become
evident. My experience with these convertible lenses has been limited to
the Zeiss Anastigmat, Series VII _a_, of which I am now using a No. 10
with a combined focus of eight inches, the front and rear lenses both
having a focal length of fourteen inches. This combination is preferred
to one in which the component lenses are of different foci, because of
the greater speed of the two when combined, and furthermore, because,
being of the same focus, they could, if occasion arose, be used in a
twin-lens box. The speed of the combination is registered at F. 6.3;
that of the single lenses at 12.5. With the former the most rapid
exposures can be made successfully, while the latter are sufficiently
fast to permit of ordinary instantaneous work. This lens is stated to
cover a 5 × 8½ plate, and when in use on a 4 × 5 camera gives a high
degree of illumination and perfect definition.
The telephoto lens may be employed in certain kinds of bird photography
with not unsatisfactory results. Its disadvantages are lack of speed, an
exposure of at least one half a second to a second being required at F.
8 in bright sunlight, the necessity of extreme care in focusing, and of
absolute rigidity of the camera at the time of making the exposure. In
short, the telephotographer needs more time, both before and after
pressing his bulb, than the bird photographer is often accorded.
However, with such subjects as nests high in trees or on cliffs, Herons
and other shore-inhabiting birds, Ducks on the water or Hawks perched in
leafless trees, the telephoto will be found serviceable.
Negatives are frequently secured in which the figure of the bird, while
small, is sharp, when, by enlargement, a desirable picture can be made
of what in the original was too small to be easily distinguishable. An
increase in size of two diameters is possible from any fairly sharp
negative, but if the object be in perfect focus an increase of four
diameters may be made.
These enlargements may be made with an enlarging camera or with the aid
of a Nehring enlarging lens, which is placed between the front and back
lenses of the view lens, when, with the ordinary long-focus camera, a
magnification of about four diameters may be obtained, the image being
thrown on to a piece of bromide paper in the plate holder.
Through enlargement many apparently worthless negatives become of value,
and in some instances pictures can be made from different parts of the
same negative. From the sportsman-photographer’s standpoint there is,
however, one objection to the use of a magnifying lens. It gives
deceptive results, and those who are not familiar with its powers are
apt to accord the photographer undue praise for his apparent skill in
successfully approaching some bird or beast which may have been far out
of range. A not wholly unrelated kind of enlargement is sometimes
applied to the contents of creels and game bags!
But the animal photographer is so heavily handicapped that in this case
the end assuredly justifies the means. As a matter of information,
however, it seems eminently desirable to accompany all enlarged pictures
by a statement of the extent of their magnification, and throughout this
book this plan is followed. Consequently, when there is no mention of
enlargement, it may be accepted as a fact that the print from which the
reproduction was made was obtained from the negative by contact.
In illustration of these suggestions in regard to the proper lenses for
bird photography, a series of pictures is presented which shows the
results to be obtained under the same conditions with different lenses.
[Illustration: 2. Lens Test No. 1. Mounted Flicker on fence post,
distance fifty feet. Eight-inch focus, Zeiss Convertible, No. 10, Series
VII _a_ lens; diaphragm F. 8, ¹⁄₂₅ second; Cramer “Crown” plate.
Photographed at noon, in sunlight, November 30, 1899.]
[Illustration: 3. The bird in Test No. 1 enlarged about three
diameters.]
Placing a mounted Flicker (_Colaptes auratus_) on a fence post, and
setting up my tripod at a measured distance of fifty feet, a series of
test exposures was made, of which three are presented as follows:
First,^2 eight-inch lens (Zeiss Convertible Series VII _a_, No. 10),
stop F. 8, time ¹⁄₂₅ second; second,^4 fourteen-inch front lens of the
combination, stop F. 16 (equivalent to F. 4 of the eight-inch); third,^6
telephoto attachment with eight-inch lens, twenty-one-inch bellows, stop
F. 8 of the eight-inch, time one second. Commenting on the results of
these tests it may first be mentioned that in the “Unicum” shutter
employed exposures of a so-called “¹⁄₁₀₀” and “¹⁄₂₅” seconds gave
exactly the same results both with the combined eight-inch lens and the
front fourteen-inch lens; the actual time, however, was doubtless not
far from ¹⁄₂₅ of a second. The negatives, therefore, show, in the first
place, that the long-focus lens is capable of doing fairly rapid work.
Continuing our comparison, we observe that the eight-inch gives a fairly
wide field, excellent depth of focus, but a very small image of the
bird, for which alone the picture has been made. With the fourteen-inch
we decrease the extent of the field nearly one half and almost double
the size of the object pictured. This, however, has been done at the
loss of depth of focus, not even the first of the line of posts running
directly into the background being sharply defined, while with the
eight-inch all are in focus.
[Illustration: 4. Lens Test No. 2. Same subject, distance, plate, and
date as Test No. 1. Front lens (fourteen-inch focus) of Zeiss
Convertible, No. 10; diaphragm F. 16; ¹⁄₂₅ second.]
[Illustration: 5. The bird in Test No. 2 enlarged about three
diameters.]
The telephoto gives an enlargement of about six diameters of the image
thrown by eight-inch lens, and three diameters increase of that of the
fourteen-inch lens. It practically restricts the picture to the
immediate surroundings of the bird, and is without focal depth.
[Illustration: 6. Lens Test No. 3. Same subject, distance, plate, and
date as Tests Nos. 2 and 3. Eight-inch Zeiss Convertible, Series VII
_a_, No. 10, with telephoto attachment; diaphragm F. 8; twenty-one-inch
bellows; one second (½ second was later found to be full time).]
Having now made three good negatives in the field, we may, by
enlargement, improve on the image of the bird obtained. The
possibilities in this direction are clearly shown by the three
enlargements accompanying the contact prints from their respective
negatives. In each instance the enlargement is about three diameters,
and the telephoto negative of course furnishes the most satisfactory
picture. When the difficulties of telephotography are considered,
however, and the ¹⁄₂₅-second exposure of the fourteen-inch lens, which
permits of hand work, is compared with the one second of the telephoto,
we believe that for general work in photographing birds a lens having a
focal length of at least fourteen inches will be found the most
satisfactory. It should be added that, in order to make them wholly
comparable, the three contact prints as well as the enlargements were
made on enameled bromide paper.
[Illustration: 7. The bird in Test No. 3 enlarged about three
diameters.]
_The Shutter._—For fairly rapid, slow, and time exposures, a lens
shutter, such as is sold with trade cameras, will be found suitable.
Simplicity and noiselessness are the chief requirements in this kind of
a shutter. The “Iris Diaphragm” shutter is noiseless when used for slow
exposures of two or three seconds, a matter of much importance in making
time pictures of sitting birds, who are apt to turn their head if they
hear the click of the shutter. This shutter, however, does not respond
quickly in slow exposures and is very heavy, a disadvantage in
telephotography.
The “Unicum” shutter is lighter, responds quickly, has a lever to which
a thread may be attached for making exposures from a distance, can be
easily diaphragmed from the rear, but is not wholly noiseless. There are
also other shutters, each possessing good points of its own, and the
selection of any one of them for use in medium rapid, slow, or time work
can be left to the photographer, who should, however, remember that the
time scales on these shutters represent degrees of difference and not
exact measurements of time, and that there is great variation in the
exposures of different shutters of the same make when similarly
adjusted. Thus the “one fifth of a second” of one shutter may be
equivalent to the “one second” of another. The scale on most of these
shutters calls for a speed not exceeding a ¹⁄₁₀₀ part of a second, but
this is far too slow an exposure to successfully photograph a flying
bird at short range where a speed of at least ¹⁄₅₀₀ of a second is
required.
For very rapid work the choice is limited to one kind of shutter—that
is, the focal-plane, which in effect is a curtain with an adjustable
slit which is placed directly in front of the plate. Great speed with
this shutter is in part secured by increasing the tension of the spring,
which acts as its motive power, but more particularly by decreasing the
width of the slit. Assuming, therefore, that it takes one second for the
slit to pass from top to bottom of a plate four inches high, and that
the slit is one inch in width, it follows that each portion of the plate
is exposed to the light for a quarter of a second. Decreasing the width
of the slit one half, proportionally reduces the time of the exposure,
and by this means, in connection with an increase in the speed with
which the curtain is moved, an exposure of ¹⁄₁₀₀₀ of a second is
possible.
In addition to possessing the advantage of great speed, this shutter
also passes a higher percentage of light than a lens shutter even when
the actual time of the so-called exposure is the same. This is due to
the fact that the lens opening is in no way affected, it being the same
throughout the exposure. With a lens shutter, on the contrary, the full
value of the opening is given for only a fractional part of the
exposure, the parts of the shutter more or less filling the opening
during the rest of the time. With a focal-plane shutter, therefore, one
may do rapid work under conditions where a lens shutter could not be
successfully employed; time exposures, however, can not be made with the
focal-plane shutter, and for all-around work the camera should be fitted
with both a lens and a focal-plane shutter.
The reflecting camera, as before stated, is fitted with a focal-plane
shutter, and, as described, it is released by pressing the lever, which
raises the mirror. Lens shutters, however, are released by a pneumatic
bulb, or in some cases by a thread or string. When the exposure is to be
made from a distance as much as one hundred feet of tubing may be
employed. With any length of over twenty-five feet an extra large bulb
is required. The ordinary tubing sold by photographers will not be found
so well adapted to long-distance work as a less elastic kind, which does
not so readily yield to pressure and transmits a larger portion of the
force applied when squeezing the bulb.
_The Tripod._—A stout two-length tripod is to be preferred to one of the
slender multifolding type, in which stability is sacrificed to weight
and size. The legs, except the inner sides of the upper section into
which the lower section slides, and brass work should be painted bark
color in order to make them as inconspicuous as possible. For use in the
water a metal tripod will prove more serviceable than one of wood.
A very useful substitute for a tripod is the “Graphic” ball-and-socket
clamp designed more especially for bicycle camerists. With it a camera
can easily be attached to the limb of a tree, rung of a ladder, or, by
screwing a block on to the head of the tripod, it may be employed in
connection with the tripod—in fact its applicability will be evident to
every one using it.
_Plates._—Among the many excellent brands of plates now offered to
photographers there is really very little difference. However, it is
advisable to select the one you think the most rapid and use it to the
exclusion of all others. Under certain circumstances—in photographing
Robins, for instance—isochromatic plates will be found desirable, and
where a strong head light can not be avoided nonhalation plates may be
employed.
So much industry, skill, and patience are generally required of the bird
photographer before he makes an exposure that he should guard against
all chances of failure from the photographic side. It is therefore
advisable to thoroughly test plates which it is probable may be exposed
on a very difficult subject. Under no circumstances should the plate
holders be needlessly exposed to the light, and when the camera is to be
left for an indefinite period with the slide drawn from the holder and
plate ready to expose, it should be carefully wrapped in the dark-cloth.
_Blinds._—As the sportsman constructs blinds in which he may conceal
himself from his prey, so the bird photographer may employ various means
of hiding from his subjects. The Keartons recommend an artificial tree
trunk for use in wooded places and an artificial rubbish heap for open
fields. The former may be made of light duck, painted to resemble bark,
and placed over a frame.
The frame of the Keartons’ is of bamboo, but I find white pine answers
very well, the main things to be considered being lightness and
portability. The frame should therefore be collapsible in order that it
may be easily packed.
The Keartons’ field blind or “rubbish heap” consists of an umbrella, to
each of the ribs of which strips of bamboo four feet in length are tied.
This is then covered with light brown holland and wisps of straw tied
over it in such a way as to “virtually thatch the whole structure.”
Doubtless cornstalks properly arranged would make an excellent field
blind.
It is difficult to carry one of these blinds in addition to a camera,
etc., without assistance, and I fear that the inconvenience attending
their use will restrict them to the few enthusiasts who count neither
time, labor, nor cost in attaining a desired end.
For my own part, I prefer, when possible, to conceal my camera and make
the exposure from a distance rather than to weight myself with a
portable blind and to endure the discomforts of being confined within
it.
_Sundries._—The bird photographer will find that he requires numerous
articles not usually to be found in the regulation photographic outfit,
as, for example, climbers for ascending trees and stout cords for
hauling the camera up after him; a dark-cloth, green in color, to aid in
disguising the camera, and a mirror. The latter should be of plate
glass, and measure at least twelve by ten inches. A good plan is to buy
a piece of glass of desired size and frame it simply in white pine. It
may then be attached to a limb, a stick driven in the ground, or other
convenient object, by means of the ball-and-socket clamp mentioned under
Tripods, which may be screwed into the back or the outer border of the
frame. Such a mirror will reflect sunlight many yards to shaded nests,
where, in photographing old or young birds, a quick exposure is
necessary. A vest-pocket mirror, for use in reflecting the reading of
the diaphragms or time on the shutter, will permit one to make the
desired changes from the rear, and thus prove helpful when conditions do
not permit one to work in front of the camera.
A device which might be arranged on the principle of a trap, the trigger
to be sprung and exposure made when the bait is taken, would doubtless
capture some interesting pictures. An apparatus connected with an
automatically fired flash-light, has been employed by Mr. G. A. Shiras,
of Pittsburg, in photographing deer at night, with phenomenal success.
The connection with the camera shutter was so made that the deer, in
walking, touched a cord which exploded the flash-light, and, at the same
moment, made the exposure. The light weight of most birds, however,
requires a much more delicate apparatus, while an even greater
difficulty is found in the movement caused by the release of the
trigger, which startles the bird just as the exposure is made.
Thus far in my experiments I have been unable to overcome these
objections, but I trust some other bird photographer will be more
successful.
Those who are ambitious in the direction of cliff photography I would
refer to the Keartons’ admirable treatise on the subject in their Wild
Life at Home, for a description of the paraphernalia needed and the
manner in which it should be used. My own experience in this line is
limited, and I confess to the utter absence of a desire to increase it!