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THE BRITISH JOURNAL OF PHOTOGRAPHY. November 1, 1860, p.310
OBSERVATIONS ON ALBUMENISED PAPER AND ALKALINE GOLD TONING.
No. III.
BY C. JABEZ HUGHES.
ALBUMENISED PAPER.--Photographers are not agreed whether the,
best albumenised paper is that which has the highest gloss. The
majority certainly run after the glitter; but the old proverb holds
good again, for the most perfect paper cannot be made to take the
same high glaze that some inferior ones do. This rage for gloss has
a great tendency to drive albumenisers to adopt some of those tricks
they have recently been charged with--of using gelatine, stale:
eggs, and other objectionable means to produce this strong glaze.
Admitting that albumen-brilliancy is desirable, its production
should only be by legitimate means. An intensely high glaze is not
the only thing needful in an albumenised paper. This fact cannot be
too strongly insisted on; and photographers must be made aware that
albumenisers cannot give any glaze they please indifferently on all
papers, and that some very good papers, though taking a very high
surface, will not compete m that respect with the commoner and, in
other respects, inferior French papers.
Albumenising paper is an operation requiring great care and
knack. In consulting with several who do it on a large
commercial scale, I find they have few or no secrets. Their, success
lies in that careful manipulation acquired only by considerable
practice and experience. For the supply of eggs they depend on the
egg merchants; though I know one party who uses only fresh-laid
eggs, and he charges many of the defects of the common albumen to
the foreign eggs being packed in lime, which, permeating the porous
shell, acts on and inures the albumen, the presence of the lime,
according to the statement, being evident in the taste of the
albumen. The quantity of eggs consumed in preparing photographic
paper must be very great. In one establishment I recently saw a box
containing 1100. I was assured that two of these were used every
week. This would give upwards of 114,000 per annum used by this
person alone!
When the highest glaze is wanted it is the practice to add no
water whatever to the albumen: the crystals of chloride of ammonium
or sodium are added and beaten up with it, and thus made to
dissolve. When it is in the condition to be used--some use it when a
day old; and reject it at the end of a week; some begin to use it
only when it is a week old--it is placed in dishes larger than the
whole sheet of paper: the sheets are carefully floated, and then
hung up to dry in a warm place. The rooms where the albumenising is
conducted are kept at a high temperature, it being a most important
circumstance to dry the sheet as quickly as possible after taking it
from the albumen.
Chlorides of sodium and ammonium are each used, and it is
believed that there is not much difference. On plain paper the
nature of the chloride is of consequence in affecting the tone; but
with albumenised paper it is thought that this effect is practically
ignored by the influence of the large amount of albumen. Chloride of
barium I do not find in general use.
There is a considerable agreement about the quantity of salt to
be used. From ten to twelve and a-half grains per ounce is
considered the proper quantity. One party, however, uses fifteen
grains. The sixty-grain silver solution will therefore be about the
strength required for nearly all papers.
For those who wish to albumenise their own paper, the operation
is as follows:--Obtain as many eggs as are required ounces of
solution to fill the dish to the depth of half an inch. Break the
eggs individually in a cup, being careful not to disturb the yolk;
then extract the germ, and pour the albumen in a large vessel to be
used for beating it up. By treating each egg alone, any one which
may have the yolk broken, or that is not good, can easily be
rejected;, for one bad egg may spoil the whole batch. Next add
chloride of ammonium, ten grains for each egg. Dissolve the chloride
in as little water as it will take up, and add it to the albumen:
beat the latter till it all becomes a stiff froth, and not a drop of
fluid remains. Allow it to remain for twenty-four hours, then pour
it through a fine muslin into a shallow dish. Float the paper
carefully on the albumen so as to avoid air bubbles: this is the
most delicate operation, and great knack is required to do it
properly; for if an air-bubble once occurs, although it may be
removed, it will always show in printing, therefore the sheet must
be so laid down that none be formed. The length of time the sheet
must remain on the albumen depends on the kind of paper. Generally
it is from sixty seconds to two minutes. If the paper remain too
long the albumen sinks deeply, and the surface dries dull. In
lifting the sheet off' as much skill is required as in laying it on.
It must be lifted with one steady regular motion, any hesitation or
stopping causing a streak or series of streaks. The sheet must be
suspended by two corners, so that it may drain and dry in a
uniform manner. When the albumen is set the sheet may be dried by
the fire: the quicker it is dried the greater the glaze. When dry
the operation is, strictly speaking, finished, and the paper. ready
to be silvered for printing; but, as usually prepared for commerce,
it passes through another operation--that of pressing.
Formerly it was thought necessary to smooth the paper with a hot
iron to coagulate the albumen prior to sensitising, and as this was
inconvenient on a large scale, it was sent to the
hot-presser's Though it has since been discovered that the
silver solution itself sufficiently coagulates the albumen yet the
pressing--now cold pressing--remains.
This process the albumenisers cannot manage themselves, but send
the paper to the card glazers', who, for a small charge, do it for
them. The, operation is simple. Two highly-polished steel plates,
kept expressly for this work, are provided, and two sheets of
albumenised paper, back to back, and albumenised surfaces to the
steel plates, are placed between them. They are then put under heavy
rollers and, submitted to powerful pressure. This takes out the curl
the paper gets from albumenising, and causes it to lie flat. It also
communicates a peculiar gloss and apparent fineness of surface,
which is, however, purely artificial, and disappears when wetted;
and it is worth while considering whether photographic paper should
pass through this operation. It is a question of advantage and
disadvantage. By the process of pressing the paper loses its
curl, acquires a delusively fine face, and lies invitingly
smooth in a tradesman's drawer; but for practical end, "its sole and
only recommendation is, that it lies more easily on the silver
solution.
The disadvantage of the pressing is, that the paper passes from
those who understand it and are interested in keeping it clean and
perfect, into the charge of careless boys, who handle it with dirty
hands; that particles of dust and dirt that adhere even to polished
steel plates are ground into the surface; and that; often the
albumen itself is much injured in the rolling, sometimes literally
crushed, to the entire prevention of getting a good print, through
too much pressure being used. Is it desirable, for so small an
advantage, that so much risk should be run ? I think not. Some
persons who prepare a great deal of paper have set their faces
against it, and will not have their paper rolled. Others laughingly
say, "the public like it--are tickled with a shining face; that high
glaze, like charity, covers a multitude of sins; that though it is
little else than a sham, let them have it who know no better." The
grain and structure of a paper is very much opened up in
albumenising, so that its nature can be judged; but, if it be
pressed, an apparent fineness is communicated that cannot be relied
on, and one means of forming an estimate is removed. Nearly all the
finger marks--how frequently a fine and unnecessarily perfect
representation of the whole five digits!--are attributable to
handling with dirty hands during the pressing operation.
I strongly recommend photographers to discontinue the use of
rolled or pressed paper.
When the printing is all over, and the picture mounted on card.
board, then is the time to press it, and take full advantage of the
fine surface to be communicated.
Is gelatine used by albumenisers to give increased glaze .to
their papers? The assertion is frequently made, and there may be
truth in it; but, from inquiries I have instituted in very many
quarters, I can get no evidence of it.. The nearest approach is the
practice, said to be adopted by one party, of sponging his sheets of
paper, first with a, weak solution of gelatine, then having them
pressed, next albumenising, and finally pressing again; .but this
operation is only equivalent to giving the paper an extra sizing to
create a harder surface, so that the albumen, by being more
superficial, will give greater glaze. Those who adopt adulterations
generally do it for cheapness; but any paper passing through a,
double operation of this nature must be enhanced in price.
I have certainly met with papers, albumenised in France and sent
to this country, that have had a very suspicious odour; but I think
the practice of all respectable parties in this country is to use
albumen only. Albumen is, however, used in different states. When
newly prepared it does not give such high glaze as when it is older.
If albumen prepared yesterday be used to-day, it will not give much
glaze--it sinks into the paper: to-morrow it will do better: in
three or four days time it will .be in first-rate order. This,
however, depends on temperature and period of the year. One of the
troubles of the albumeniser is the keeping his albumen in order, and
when it is in its best condition, to use it up as rapidly as
possible. Some persons keep their albumen for a fortnight or more
before they use it-the object being to concentrate it, to evaporate
the water from it, and make it thick; and in this state it will give
a very high glaze upon even a porous paper. But this is certainly
pushing things too far, and the paper will show it; for instead of
being white it will be decidedly yellow, from the thick layer of
decomposed albumen. When paper prepared in this manner is moist,
both the colour and adhesiveness of
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