COPYING PRINTS AND DAGUERREOTYPES
After learning how to make enlarged prints from his small negatives,
the amateur may profitably turn his attention to the copying of
photographs and other pictures at home. The object to be copied may
be an old Daguerreotype, tintype, or faded portrait, valued because
of its associations, or it may be a painting, map, college diploma
or manuscript we desire to reproduce. Again, we may want to make a
slightly enlarged portrait of a single figure from a group. The work
is very interesting and has few, if any, difficulties which cannot be
easily overcome _provided that we can rack the bellows of our camera
out beyond twice the focal length of the lens_. This is the principal
difficulty in copying with a hand camera; its bellows’ extension is
so limited. As long as it is a question merely of making a small
reproduction from a large original the difficulty does not appear.
But when we attempt to make a copy the same size as the original (as
to copy a 4 x 5 picture on a 4 x 5 plate), then we are confronted by
the rule that _in such a case the distance between the lens and the
original, and the distance between the lens and the focusing screen,
must both be fully twice the focal length of the lens_.
Thus, in copying a 4 x 5 picture upon a plate 4 x 5, we can readily
adjust the distance required between lens and object, but it is
impossible to focus the image sharply because we cannot rack out the
bellows far enough to give the required distance between lens and
focusing screen. If we have a double-extension its extra length of
bellows will help us out of the difficulty. Failing this, a short focus
(wide angle) lens fitted to our regular camera may enable us to get
the desired size and sharpness in our copy. Or, if we do not possess
either of these, we may make a wooden extension front and fit it into
the front-board of our hand camera in the place usually occupied by
the lens. The lens, of course, must be fixed at the front end of this
light-proof wooden extension front. In this way we gain the desired
distance of separation between the lens and plate. A still simpler plan
is to make use of a supplementary lens, such as the _Ideal Copying
Lens_, which, slipped on at the hood of our regular lens, will shorten
its focal length and so enable us to solve the problem.
The original to be copied is fixed in a vertical position near a
window which faces an unobstructed north light. The lighting should
be directed to evenly illuminate the whole of the picture to be
copied, and we must be careful to avoid reflections, or any defect in
lighting which will cause the grain or texture of the original to be
too prominent. It is also essential that the centre of the lens be in
line with the centre of the original being copied, and the original
absolutely parallel with the plate. The camera may be fixed to its
tripod or placed upon boxes on a table; the first method is the
best as obviating any possibility of movement during the immediate
preparations before exposure. Focusing should be done with the largest
stop, and a smaller stop inserted before exposure. In focusing we
must look especially to the corners of the plate, to see that they
are well lighted and that the definition there is as good as at the
centre of the plate. The exposure, in a fairly bright light, a plate
of medium rapidity and stop _f_/32 will range from 35 seconds to 5
minutes according to the subject and the amount of enlargement or
reduction. Copies of printed matter will require exposure according to
the condition and tint of the paper; thus a yellowed engraving will
require three times the exposure given to a page from a new hymn-book.
In copying manuscripts or any object having color a slow orthochromatic
plate, or a ray-filter, offers practical advantages. The latter, used
with a plain plate, is especially valuable in copying blue prints.
A full exposure is always preferable to one slightly undertimed. In
development, the points to be attended to are intensity and contrast.
The grayness of tone peculiar to copied photographs is generally due to
the want of intelligent development. Rodinal or citol and hydroquinone
have all proved valuable in my own experience in this work. A good
formula is as follows, A: Hydroquinone, 75 grains; sodium sulphite, 2
ounces; potassium bromide, 15 grains; water, 8 ounces. B: Caustic soda,
180 grains; water, 10 ounces. For use, take 2 ounces of A and add a
quarter ounce of B. Dilute with water as the plate may indicate after
the first appearance of the image.
The copying of daguerreotypes is a branch of work which the amateur can
pursue at home with pleasure and profit. Much has been written about
the subject, special stress being laid upon the necessity of “cleaning”
or restoring daguerreotypes before their reproduction. As this is
not invariably necessary, my first word will be a word of caution.
The Daguerrean image, although in a sense absolutely permanent, is
extremely delicate in structure, and may most easily be destroyed by an
incautious touch. As a rule the Daguerrean artist did his work well,
and if the original to be copied shows no signs of tarnish, it will be
well to set about its reproduction without any attempt at restoration.
If the surface under the glass cover in the little case shows dust,
remove the glass and carefully clean it. Any dust on the surface of
the picture image itself may be removed by very lightly passing a soft
camel’s-hair brush over it. On no account must the surface be touched
with the fingers or the most delicate material, or the delicate film
will be injured.
If the entire surface has become darkened or tarnished by the influence
of the air upon the film, some restoration is of course essential to
the best results. To effect this, remove the silvered plate from the
case and place it, image uppermost, under a box lid or other protector
from dust, etc. Now put a small piece of potassium cyanide (deadly
poison) into a graduate, and pour over it an ounce or two of water.
Holding the daguerreotype by the corner with a pair of pliers, rinse it
in clear running water; then pour over it the weak cyanide solution
(a 3-per cent solution is usually employed), and return it to the
graduate. Repeat this operation several times until the discoloration
quite disappears. Within a few minutes the daguerreotype will appear
as fresh and as brilliant as when first made. Wash well in running
water, and then, before the surplus water has time to collect in tears
upon the image, begin to dry the plate gradually over a spirit lamp,
holding the plate in an inclined position so that it will dry from the
uppermost corner. The plate must not be held too long over the flame or
the thin silver film may separate from its copper support. The secret
of success is in the use of pure water for the final washings, and
the drying of the image without check or the formation of tears. The
picture should now be restored to its case, and the edges secured with
goldbeater’s skin or gummed paper to thoroughly exclude the air.
In copying daguerreotypes in their cases it is usually advisable
to turn them on one side. If fixed to an open board or support,
reflections will undoubtedly give trouble, and these are not
always visible on the ground-glass. It is therefore usual to copy
daguerreotypes placed at the end of a fairly deep box lined with
velvet, the lens being pointed at the picture through a hole cut in
a black cloth flap which covers the front end of the box. Light is
admitted through openings at the side of the box. The exposure is
necessarily protracted. Care must be taken to avoid movement during the
exposure. If the marks of the buffer—fine horizontal lines—are seen
in the resulting negative, the plate should be placed vertically and
rephotographed.