_Processes upon Paper._--The favourable manner in which the account I have
given of the Collodion process has been received, not only by your readers
in general, as has been evinced by many private letters, but also by the
numerous correspondents it has drawn forth, induces me, after some little
delay, to request space for a description of the following processes upon
paper. In giving these I wish it to be understood that I may offer but
little that is original, my object being to describe, as plainly as I
possibly can, these easy methods, and to make no observation but what I
have found to be successful in my own hands. I have had the good fortune to
obtain the friendship of some of the most successful photographers of the
day; and taking three very eminent ones, I find they have each some
peculiarities in his mode of manipulation, varying with each other in the
strength of the solutions employed, and producing results the most
agreeable to their respective tastes. Reviewing these different processes
in my own mind, and trying with patience the various results, I conclude
that the following quantities are calculated to produce an adequate degree
of sensibility in the paper, and yet to allow it to be prepared for the
action of light for many hours previous to its use, and yet with more
certainty than any other I am acquainted with. I think I may always depend
upon it for twenty-four to thirty-six hours after excitement, and I have
seen good pictures produced upon the third day. I believe it is a rule
which admits of no contradiction, that the more you dilute your solution,
the longer the excited paper will keep; but in proportion to its diminished
sensibility, the time of exposure must be prolonged, and therefore I am,
from this waste of time and other reasons, disposed to place much less
value upon the wax-paper process than many do.
The process I am about to describe is so simple, and I hope to make it so
intelligible to your non-photographic readers, that a perfect novice, using
ordinary care, must meet with success; but should I fail doing so upon all
points, any information sought through the medium of "N. & Q." shall meet
with explanation from myself, if not from other of your experienced
correspondents, whose indulgence I must beg should the communication be
deemed too elementary, it being my earnest desire to point out to
archæologists who are desirous of acquiring this knowledge, how easily they
themselves may practise this beautiful art, and possess those objects they
would desire to preserve, in a far more truthful state than could be
otherwise accomplished.
I have not myself met that uniform success with any other paper that I have
with Turner's photographic of Chafford Mills: a sheet of this divided into
two portions forms at the same time a useful and also a very easily-managed
size, one adapted for most cameras, forming a picture of nine inches by
seven, which is adequate for nearly every purpose. Each sheet being marked
in its opposite corners with a plain pencil-mark on its smooth side (vide
_antè_, p. 372.), the surface for {21} all future operations is in all
lights easily discerned. In my instructions for printing from collodion
negatives, a form of iodized paper was given, which, although very good, is
not, I think, equal to the following, which is more easily and quickly
prepared, exhibits a saving of the iodide of potassium, and is upon the
whole a neater mode.
Take sixty grains of nitrate of silver and sixty grains of iodide of
potassium; dissolve each separately in an ounce of distilled water; mix
together and stir with a glass rod. The precipitate settling, the fluid is
to be poured away; then add distilled water to the precipitate up to four
ounces, and add to it 650 grains of iodide of potassium, which _should_
re-dissolve the precipitated iodide of silver, and form a perfectly clear
solution; but if not, a little more must be carefully added, for this salt
varies much, and I have found it to require 720 grains to accomplish the
desired object.
The fluid being put into a porcelain or glass dish, the paper should be
laid down upon its surface and immediately removed, and being laid upon a
piece of blotting-paper with the wet surface uppermost, a glass rod then
passed over it to and fro ensures the _total expulsion_ of all particles of
air, which will frequently remain when the mere dipping is resorted to.
When dry, this paper should be soaked in common water for three hours,
changing the water twice or thrice, so as to remove all the soluble salts.
It should then be pinned up to dry, and, when so, kept in a folio for use.
I have in this manner prepared from sixty to eighty sheets in an evening
with the greatest ease. It keeps good for an indefinite time, and, as all
experienced photographers are aware, unless you possess good iodized paper,
which should be of a _primrose_ colour, you cannot meet with success in
your after-operations. Iodized paper becomes sometimes of a bright
brimstone colour when first made; it is then very apt to brown in its use,
but tones down and improves by a little keeping.
To excite this paper, dissolve thirty grains of nitrate of silver in one
ounce of distilled water, and add a drachm and a half of glacial acetic
acid; of this solution take one drachm, and one drachm of saturated
solution of gallic acid[3], and add to it two ounces and a half of
distilled water. The iodized surface of the paper may then be either
floated on the surface of the aceto-nitrate of silver or exciting fluid,
and afterwards a rod passed over, as was formerly done in the iodizing, or
the aceto-nitrate may be applied evenly with a brush; but in either
instance the surface should be immediately blotted off; and the same
blotting-paper never used a second time for this, although it may be kept
to develop on and for other purposes. It will be scarcely needful to
observe that this process of exciting must be performed by the light of a
candle or feeble yellow light, as must the subsequent development. The
excited paper may be now placed for use between sheets of blotting-paper;
it seems to act equally well either when damp or when kept for many hours,
and I have found it good for more than a week.
The time for exposure must entirely depend upon the degree of light. In two
minutes and a half a good picture may be produced; but if left exposed for
twenty minutes or more, little harm will arise; the paper does not
solarize, but upon the degree of image visible upon the paper depends the
means of developing. When long exposed, a saturated solution of gallic acid
only applied to the exposed surfaces will be sufficient; but if there is
little appearance of an image, then a free undiluted solution of
aceto-nitrate may be used, in conjunction with the gallic acid, the former
never being in proportion more than one-third. If that quantity is
exceeded, either a brownish or an unpleasant reddish tint is often
obtained. These negatives should be fixed by immersing them in a solution
of hyposulphite of soda, which may be of the strength of one ounce of salt
to eight ounces of water--the sufficiency of immersion being known by the
disappearance of the yellow colour, and when they have been once immersed
they may be taken to the daylight to ascertain this. The hyposulphite must
now be perfectly removed by soaking in water, which may extend to several
hours; but this may be always ascertained by the tongue, for, if tasteless,
it has been accomplished. If it is deemed advisable--which I think is only
required in very dark over-done pictures--to wax the negative, it is easily
managed by holding a piece of white wax or candle in front of a clean iron
rather hot, and passing it frequently over the surface. The superabundant
wax being again removed by passing it between some clean pieces of
blotting-paper. Although the minuter details can never be acquired by this
mode which are obtained by the collodion process, it has the advantage of
extreme simplicity, and by the operator providing himself with a bag or
square of yellow calico, which he can loosely peg down to the ground when
no other shade is near, to contain spare prepared papers, he can at any
future time obtain a sufficient number of views, which afterwards he can
develop at his leisure.
It requires no liquids to be carried about with you, nor is that nice
manipulation required which attends the collodion process.
The wax-paper process has been extolled by many, and very successful
results have been obtained: the paper has the undoubted advantage of
keeping after being excited much longer than any other; but, from my own
experience, just so much the weaker it is made, and so as to safely rely
upon its long remaining useful, so it is proportionally slower in its
action. And I have rarely seen from {22} wax negatives positives so
satisfactory in depth of tone, as from those which have been waxed after
being taken on ordinary paper. It is all very well for gentlemen to
advocate a sort of photographic tour, upon which you are to go on taking
views day after day, and when you return home at leisure to develop your
past proceedings: I never yet knew one so lukewarm in this pursuit as not
to desire to know, at his _earliest possible_ opportunity, the result of
his labours; indeed, were not this the case, I fear disappointment would
more often result than at present, for I scarcely think any one can exactly
decide upon the power of the light of any given day, without having made
some little trial to guide him. I have myself, especially with collodion,
found the action very rapid upon some _apparently_ dull day; whilst, from
an unexplained cause, a comparatively brighter day has been less active in
its photographic results. As in the previous process, I would strongly
advise Turner's paper to be used, and not the thin French papers generally
adopted, because I find all the high lights so much better preserved in the
English paper. It may be purchased ready waxed nearly as cheap as it may be
done by one's self; but as many operators like to possess that which is
entirely their own production, the following mode will be found a ready way
of waxing:--Procure a piece of thick smooth slate, a trifle larger than the
paper to be used; waste pieces of this description are always occurring at
the slate works, and are of a trifling value. This should be made very hot
by laying it close before a fire; then, covered with one layer of thick
blotting-paper, it will form a most admirable surface upon which to use the
iron. Taking a piece of wax in the left hand, an iron well heated being
pressed against it, it may rapidly be made to flow over the whole surface
with much evenness, the surplus wax being afterwards removed by ironing
between blotting-paper. When good, it should be colourless, free from
gloss, and having the beautiful semi-transparent appearance of the Chinese
rice-paper. To iodize the paper completely, immerse it in the following
solution:
Iodide of potash 200 grains.
Mannite 6 drachms.
Cyanide of potash 5 grains.
Distilled water 20 ounces.
Allow it to remain three hours, taking care that air-particles are
perfectly excluded, and once during the time turning over each sheet of
paper, as many being inserted as the fluid will conveniently cover, as it
is not injured by after keeping. It should be then removed from the iodide
bath, pinned up, and dried, ready for use. When required to be excited, the
paper should, by the light of a candle, be immersed in the following
solution, where it should remain for five minutes:
Nitrate of silver 4 drachms.
Glacial acetic acid 4 drachms.
Distilled water 8 ounces.
Being removed from the aceto-nitrate bath, immerse it into a pan of
distilled water, where let it remain about a quarter of an hour. In order
to make this paper keep a week or two, it must be immersed in a second
water, which in point of fact is a mere reduction of the strength of the
solutions already used; but for ordinary purposes, and when the paper is to
be used within three or four days, one immersion is quite sufficient,
especially as it does not reduce its sensitiveness in a needless way. It
may now be preserved between blotting-paper, free from light, for future
use. The time of exposure requisite for this paper will exceed that of the
ordinary unwaxed, given in the previous directions. The picture may be
developed by a complete immersion also in a saturated solution of gallic
acid; but should it not have been exposed a sufficient time in the camera,
a few drops of the aceto-nitrate solution added to the gallic acid greatly
accelerates it. An excess of aceto-nitrate often produces an unpleasant red
tint, which is to be avoided. Instead of complete immersion, the paper may
be laid upon some waste blotting-paper, and the surface only wetted by
means of the glass rod or brush. The picture may now be fixed by the use of
the hyposulphite of soda, as in the preceding process.
It is not actually necessary that this should be a wax-paper process,
because ordinary paper treated in this way acts very beautifully, although
it does not allow of so long keeping for use after excitement; yet it has
then the advantage, that a negative may either be waxed or not, as shall be
deemed advisable by its apparent depth of action.