TRANSFER METHODS
SIMPLE TRANSFER.—Bromoil prints, which have been inked up but not
defatted, can be effectively used as print-plates, from which pulls
on any desired plain paper can be taken. The process of making such
transfers is simple and certain and opens a whole series of new
possibilities to the amateur. Briefly the method is as follows:
The greasy ink on a finished bromoil print lies on a gelatine film. If
the inked print is brought into contact with any uncoated paper and
passed between two rolls under pressure, the ink transfers from the
bromoil print to the paper. Obviously the picture thus produced is
laterally reversed, which must be kept in view in preparing bromoil
prints for transfer. Bromide enlargements to be used for transfer should,
therefore, be made reversed.
The bromoil print can again be inked up after this process and again used
for transfer; with bromide papers with resistant gelatine films this
process may be repeated many times.
The advantages which bromoil transfer offers are as follows: in the
first place we attain the end so often sought of being able to use any
suitable paper for making photographic prints, which opens a new field
for artistic endeavor. Obviously, also, any desirable oil-printing ink
can be used, so that the whole gamut of colors is at the command of the
operator.
The personal control of the tone values of the print, which attains its
maximum development in bromoil printing, is equally possible in bromoil
transfer.
The picture is obtained on an uncoated paper and, therefore, the prints
are of a character which hitherto could scarcely be obtained.
The finished prints, if the paper is properly chosen, can be retouched as
much as desired.
From a single bromoil print a whole series of impressions can be
obtained, which may either be all alike or quite different. They can
be made heavy or light, in one or more colors, or even in polychrome,
according to how the re-inking is done.
The transfer process is also very cheap, as the papers used are naturally
much cheaper than photographic printing papers. Moreover, one can make
the pulls from small bromoil prints on larger sheets, so that the picture
may be suitably surrounded with white margins.
The following details should be observed in the preparation of bromoil
transfers:
The bromoil print designed to be used as a print-plate can be made on
papers of the characters described in Chapter I, page 13. The bromide
paper need not necessarily be free from structure, for with the pressure
to which the sheet is subjected in the transfer, the effect of the
structure is lost. The structure of the bromide paper may also be reduced
by passing the bleached print through the rollers of the transfer machine
under heavy pressure before inking. _The bromide print or enlargement
must be kept very clean and free from fog_, since the cleanness of the
high lights plays a very important part in the transfer. The inking is
done in the usual way; only one should use all possible means to obtain
the greatest possible cleanness of the high lights, and good modulation.
After inking-up, any brush hairs and especially any little particles of
ink that are not broken up must be removed, as the latter are especially
troublesome in the transfer.
The process succeeds best when the bromoil print has as high a relief
as possible. Such a relief facilitates and requires the use of inks of
soft consistency; soft inks adhere to the gelatine film far less firmly
than harder ones and, therefore, transfer very much more easily to the
transfer paper. A simple experiment makes this fact very clear: if the
tip of the finger is placed on a part of the bromoil print worked-up with
hard ink, some of the ink sticks to the finger, but at the most there
is formed on the print an impression of the tip of the finger, as the
place touched still retains the greater part of its ink. If, however,
the tip of the finger is placed on a part of the print worked up with
soft ink, the latter will be almost entirely removed. This may serve to
show why bromoil prints which have been entirely or chiefly worked up
with hard ink cannot be entirely transferred to the transfer paper. The
shadows especially, when covered with hard ink, are likely to appear much
reticulated in consequence of the imperfect transfer of the ink.
_To obtain with certainty a faultless bromoil transfer, soft ink should
therefore be used_; the softening of the ink must naturally not exceed a
certain limit, because otherwise the high lights will take the ink and
a clean pull cannot be obtained. In order to be able to use a soft ink
successfully, the relief of the bromoil print must as a rule be kept
rather high; hence usually water baths of suitably high temperature
should be used. It may, however, happen, especially with contrasty
prints, that the gelatine in the high lights becomes too soft, and if it
is not already damaged when taken from the warm water, it pulls off in
inking-up or in the transfer. In order to avoid this, it is best to use
the ammonia bath described on page 45.
Bromoil prints which are to be used for transfer must, as already
mentioned, always be kept very clean. This is necessary for the following
reasons. In the transfer the ink on the high lights transfers completely
in every case to the transfer paper, for the high lights are in the
highest relief, and the ink adheres to them very lightly. On the other
hand the ink is generally not completely removed from the shadows, as
they have the lowest relief and, in consequence of their tanning, the
ink adheres to them more tenaciously. Thus it happens that the transfer
is usually somewhat shorter in gradation than the original bromoil.
Allowance must be made for this, and the bromoil print should be made
considerably more brilliant than the transfer ought to be, unless
low-toned transfers are intentionally sought.
In order to obtain clean, sharp edges the bromide print when dry should
be cut to the desired size and a small tab of paper left at one corner,
which is useful for hanging it up in the further processes, whereby any
damage to the film of the picture itself is avoided. This little tab
should be cut off just before inking. If a plate mark is desired, the
print should be made with a suitable narrow white margin.
The finished bromoil print can be immediately used for the transfer. If
it is not used at once, it remains fit for transfer until the ink begins
to harden.
Any desired kind of paper may theoretically be used for the transfer;
but obviously, the success of the transfer greatly depends on the choice
of the paper. The finest effects are obtained on matt and absorbent,
but strong and well-made papers, the very best being papers intended
for copper-plate printing. As the ink penetrates into the fiber of
such papers to a certain extent, they give beautiful transfers with
an absolutely matt surface. Absorbent papers also make it possible to
transfer almost all of the ink from the bromoil. It is different with
sized or highly calendered papers. With these, the ink only penetrates
a very little way because of the film of size. The ink, therefore, lies
chiefly on the surface of the transfer and appears glossy in the shadows;
also, as it is not sufficiently absorbed by the transfer paper, the
transfer of the ink from the bromoil to the paper is usually not complete.
It is advisable, when using calendered paper, to remove the gloss by
preliminary dipping in water. Other kinds of paper also frequently give
better transfers, if they are first moistened; this is most easily done
by dipping them in water and then drying them between two blotters.
Papers which are inclined to blister because of short fibers easily split
in transfer, as parts of the surface of the paper adhere to the high
lights of the print and tear away.
Such papers may be made available for transfer, if they are coated
with two per cent wheat starch paste and allowed to dry (Process of E.
Guttmann). This is prepared by stirring up 2 g (60 gr.) of wheat starch
in a little cold water, and adding to the mixture 100 ccm (3½ oz.) of
actually boiling water, stirring well and allowing to cool.
The blistering of weak papers must be differentiated from the sticking to
the transfer paper of parts which are too much swollen; in this case the
surface of the paper remains undamaged, but the gelatine film of the high
lights is torn off and adheres to the transfer paper. As a rule, this
only occurs with those parts that are swollen too much, when too great
pressure is used in the transfer. The preliminary sizing of the transfer
paper with wheat starch prevents this also. Parts of the gelatine film
which have high relief may also be protected from sticking to the
transfer paper by a slight coat of varnish.
The best machine to use is that described by E. Guttmann on page 153. It
has proved satisfactory in every way, especially as it permits accurate
and easy regulation of the pressure of the rolls. If such a press is not
available, an ordinary burnisher can be used. The simultaneous movement
of the rolls in burnishers is produced as a rule by two gear wheels.
The inaccurate fitting of the gear teeth, however, causes periodic
irregularities in the pressure, which cause trouble in the transfer. In
order to prevent this one of the gear wheels should be removed, so that
the simultaneous movement of the rolls is produced by the pressure alone.
A burnisher is useful for the preparation of transfers only if it is
possible to obtain sufficient pressure on the rolls. On the other hand
it is difficult to obtain with this machine the necessary regulation of
the pressure during the transfer, which is described in the following
paragraph.
The following is the procedure in transferring. A blanket must first
be interposed between the rolls of the press. The best thing to use
for this is two or four thin smooth cards, which may be covered at
top and underneath with two sheets of thin linoleum. The latter are
not absolutely necessary. The print may now be introduced into the
machine either by entirely removing the blankets, or by rolling them
out far enough so that the middle sheets can be easily bent away from
one another. The position of the transfer on the transfer paper should
be marked with a pencil, and, if a plate mark is desired, a piece of
cardboard cut to the proper size should be properly placed on the
transfer paper, and the whole passed through the machine. The transfer
paper, thus prepared, should be laid on a perfectly flat white blotter,
and the bromoil print, which should be held very carefully by the extreme
edges, should be lowered to the position on the transfer paper previously
marked with the pencil. Any small ink marks thus caused can be easily
worked out later. The back of the print should be dried with a white
blotter and then a second sheet of the same size as the bottom one placed
on it. The transfer paper with the print lying on it is thus placed
between the two sheets of blotting paper, so that the water pressed out
in the transfer may be readily absorbed.
If attention is not paid to this precaution, it may easily happen that
the transfer paper, as a result of partial moistening by means of water
pressed out of the bromoil, may become wrinkled or distorted. Then the
two blotters, with the transfer and the print between them, are placed
between the two middle cards and the transfer begun. The principle of
gradually increasing the pressure in this, which was introduced by E.
Guttmann, has proved satisfactory in practice. One begins first with
a light pressure, so that the transfer passes through the rolls with
scarcely noticeable resistance. Then the pressure should be increased
a little by tightening the upper wheel of the machine, and the work
continued in this way until a certain, not very high pressure of the
rolls is obtained, which one soon learns to estimate with a little
experience. One can now, or at any later stage, take the transfer paper
with the adhering print out of the press and, holding one part of the
print firmly down on the transfer paper, with the hand or a straight
edge, lift the free end carefully, in order to ascertain whether any and
how much of the ink has been transferred from the print to the transfer
paper.
According to the result of this observation, the print is either entirely
lifted off or the transfer continued with increasing pressure. In this
way, with careful management of the work, one is absolutely certain of
obtaining the best possible results in transferring. Still, my opinion
differs from that of the inventor as to the reason for the satisfactory
action of the gradual increase of the pressure. What happens is that in
the initial passage under low pressure the print is immediately firmly
attached to the transfer paper, so that its shifting on the transfer
paper, which previously very frequently occurred, is avoided. When this
adherence is once attained, we can proceed at once to that pressure of
the rolls which is the most favorable for the transfer of the ink, if
we are sure of it. This frequently happens when one has already made
transfers from a print. With still unknown conditions, naturally the
gradual increase of pressure is advisable.
The print, removed after the completion of the transfer, can be again
inked up immediately or later, and again transferred. Naturally it must
first be immersed in water, so that it can again take up that which it
has lost in the transfer. In the new inking-up one can use as desired
the same ink or another color, and also alter the print as seems best. If
the bromoil print, which has been once used for transfer, is to be again
used for the same purpose, it is well to completely remove any adherent
traces of ink by going over it with a swab of cotton soaked in a solvent.
It may then be dried and can be used again at any desired time.
When transfers have been repeatedly made from a bromoil print, it may
happen that the film blisters. This phenomenon is usually only noticeable
when the print is again immersed in water after the transfer; as long
as the blisters are not too numerous, they do not cause much trouble
in the transfer. The answer to the question as to how often a bromoil
print can be transferred depends on the resistance of the gelatine film.
In practice it has been observed that the number of possible transfers
varies between five and twenty-five.
The transfer process can also be used in bromoil printing as a method to
free a print that has been too heavily inked from the excess of ink; such
a print is passed through the machine together with any completely smooth
paper which is free from folds, until it has given up its excess of ink
to the paper, and it can then be soaked and inked up anew.
The process of application of ink to the dry print, outlined in Chapter
IV, can also be used to advantage in the transfer process. Any bare
spots on the finished transfer can be inked up at will, by dabbing on
ink of any tone value with the oil-printing brush; thus the sky, which
may not be satisfactory, may before transfer be wiped quite clean on
the print, the outlines of the landscape cleared up with a brush dipped
in ammonia water if necessary, and the values of the sky put in on the
finished transfer. This procedure is particularly advisable in polychrome
transfers, with which a blue sky flecked with clouds can be easily
obtained in this way.
The subsequent application of ink to the finished transfer finally offers
the possibility, by tinting the whole transfer with a very delicate
coating of a suitably chosen ink, of imparting a different mood to the
picture. Thus, for instance, one may give a transfer made on white paper
a faint yellowish tint; it may be effective to surround the picture with
a border of this tint, using a suitable mask to obtain sharp outlines;
this yellowish tint is only visible in the high lights, as it does not
show in the deep shadows. In similar fashion a darker tint surrounding
the print may be put on with ink and brush.
It is obvious that the transfer, especially when fresh from the press,
can be easily and thoroughly retouched with rubber, water-color or
charcoal; first of all those places should be treated from which the ink
has been removed in consequence of the unavoidable touching of the print
with the fingers, or to which the ink has not transferred for any reason.
With transfers fresh from the press, any places that are too dark can be
easily lightened with the rubber.
The transfer very soon dries. Obviously it does not require defatting.
The inks act better on the absorbent transfer paper than on the bromoil
print itself, as they sink into the paper instead of remaining on the
surface of a gelatine film. The final result no longer resembles a
bromoil print, but has its own individual character and is a product
which it is difficult to compare with the bromoil print as regards
esthetic effect. The bromoil print has a certain charm which is lacking
in the transfer and vice versa. In any case the transfer process is worth
attention, since on the one hand it can be of practical value because of
the possibility of the duplication of bromoil prints, and on the other
hand it enables one to use varieties of paper which were not hitherto
available to the amateur.
COMBINATION TRANSFER.—In order to render possible the reproduction
of every possible tonal value of the negative, I have worked out the
_combination transfer process_ outlined in the following paragraphs. The
essence of this process lies in the fact that two or more transfers can
be made on one transfer sheet, which differ so much in their quality that
_each of them reproduces a different series of tone values_, which then
supplement one another on the transfer.
This is attained either by executing the two superposable transfers
with _inks of different consistency_, or by _the use of two prints of
different gradation_ to make one transfer.
COMBINATION TRANSFER WITH ONE PRINT-PLATE.—The bromoil print used as the
print-plate must be made on a sheet of bromide paper, which reproduces
the tone values of the negative as closely as possible, without showing
any hardness. The lights must be clean and all the half-tones present;
it is, however, neither necessary nor desirable that the shadows should
be too dense. In making the bromide print from a moderately difficult
negative one should use the process, outlined on page 23, or developing
slightly and then completing the development in a dish of water. Bromide
prints of this kind are necessary because they satisfy the most rigorous
requirements in the high lights and half-tones, while the depth lacking
in the shadows is produced by the repeated transfer.
On the print thus prepared two bromoil prints, differing entirely from
each other in character, are made, one of which we will call the _shadow
print_ (Kraftdruck) and the other the _high light print_ (Lasurdruck).
This phraseology does not coincide, however, with the similarly named
terms which are familiar in gum printing; the middle-tone print usual in
gum-printing is wanting here and is also unnecessary, since each of the
two partial prints contains a part of the middle tones, and, therefore,
when added together, they give a picture perfectly correct in tone.
The _shadow print_ is executed by inking up with a stiff ink, so adjusted
to the relief that only the deep shadows and a part of the half-tones
take the ink, while the delicate half-tones are lost and the highest
lights remain absolutely uninked. Having suitably adjusted the ink to
the relief, one should also use the corresponding brush technique, which
was described as hard ink technique on page 87. The use of a hog’s hair
brush is advisable. Perfect cleanness of the high lights, which is very
important, should be assured by the use of art gum. The shadows must show
the full drawing, but ought not to be overinked. This shadow print should
now be transferred to the transfer paper; when it leaves the press, the
_registration marks_ must be immediately applied, so that the subsequent
transfer may come exactly in the same place. It may be remarked, that
the matching of the print to the transfer does not offer the slightest
difficulty in practice, and that the registration marks can often be
omitted entirely, especially with prints which are inked right up to
their edges, because bromoils, in making which rather thick paper is
used, leave a fairly strong impression on the transfer paper, into which
one can fit the print in the subsequent transfer.
At the same time it is safe to use the following simple registration
arrangement in every case.
When the transfer is taken from the press, draw, by means of a rule, two
parallel lines perpendicular to the side edges of the print, running over
onto the transfer paper about one centimeter or one-half an inch apart.
Also draw with the rule a line perpendicular to the upper surface of the
print, also running over onto the transfer paper. In preparing for the
next partial print, the side lines are first to be brought into exact
coincidence and then the upper line. This insures exact coincidence for
the subsequent prints.
After transfer of the shadow print, the bromoil is again immersed in
water, in which it must remain for some time, so that it again becomes
saturated with water. Only then does it regain the same size as it had
at first, for the expansion caused by the absorption of water is quite
considerable. If the bromoil is not left long enough in the water before
the second printing, it will be slightly smaller than in the first
transfer and the combination print will not be sharp.
HIGH LIGHT PRINT.—The inking up of the high light print is effected with
soft ink, so as to produce a very thin and smooth film of ink; yet here
too the high lights must be kept as clean as possible. Then this high
light print is transferred by means of the above described registration
arrangement, when as a rule the combination transfer is finished.
It may happen that one has inked up one or other of the prints too
lightly. In this case either the shadow or the high light print may be
repeated, but the amount of ink applied for this supplementary impression
must be very carefully judged, in order to avoid an overinking of the
combination transfer. By the manner of inking the constituent prints
and judgment in the quantity of ink applied, the final result may be
controlled through a wide range at will; one can, for instance, by
emphasizing the shadow print rather than the high light print, get more
contrasty effects, or, by emphasizing the high light print, end with very
soft effects.
The order in which the two prints are transferred is immaterial. In any
case, however, care must be taken that the transfer paper is well dried
out after making the first transfer; for it always takes up some moisture
in the press and then appears slightly wrinkled and distorted. If the
second transfer is made on such a damp transfer paper, the result will
obviously be complete or partial want of sharpness in the combination
transfer. After the first transfer, therefore, the transfer paper should
be hung up to dry spontaneously, not by heat, as otherwise it may alter
in size.
The process just outlined for combination transfer from a single print
will in most cases perfectly reproduce the tone values of an ordinary
negative. If negatives with a very long gradation have to be dealt with,
then the following process may be used.
COMBINATION TRANSFER FROM TWO PRINTS.—The underlying idea in using two
prints is to overcome the impossibility of completely reproducing an
extended scale of tones on bromide paper, by the use of two prints, which
are so made that they divide the scale of tones in such a way that one
end of the scale is represented by one print and the other end by the
other.
Therefore we make from the negative one hard print with well modulated
shadows and only the darker half-tones. This is obtained by short
exposure and suitable development. The high lights should show no deposit
of silver. When master of the process, it is possible to include more or
less of the middle half-tones in this partial print which is intended for
the shadow print, according to the final result desired, and this can be
readily regulated by the length of the exposure. The fewer middle tones
the shadow print contains, the more contrasty will be the combination
transfer.
The second partial print is the high light print, and must, therefore,
be kept as delicate and soft as possible, and include all the delicate
middle tones up to the highest lights. The latter may even be very
slightly veiled, yet only so far that after swelling absolutely pure
whites can be obtained. No further demonstration is needed to prove that
a combination of these two partial prints can include the whole scale
of tone values of the longest-scaled negative; for the partial print
destined for the high light print-plate gives every possible half-tone,
while the other, intended for the shadow print, imparts full depth to the
shadows without burying the details, and strengthens the half-tones, but
does not affect the clearness of the high lights.
The combination transfer is now prepared from these two prints, which
are transferred in succession to the transfer paper, the order being
immaterial. For this an accurate superposition of the two partial prints
is absolutely essential. This must be accomplished by making the two
prints of exactly the same size, with the images in exactly the same
position on the paper. This may be done by masking the negative with
black lantern-slide strips gummed on the film for contact prints and on
the glass for enlargements. The strips must be absolutely straight and
the slightest curvature avoided in sticking them down. Two prints or
enlargements, prepared from such a negative, can easily be registered.
The desired end may also be obtained by printing or enlarging the two
bromide prints under the same straight-edged mask. Care must be taken
here that the image occupies exactly the same place in the mask for both
prints. This is easily accomplished with various commercial printing
machines. In enlarging, a mask made of stiff card can be hinged to the
easel. The prints or enlargements thus made should be very carefully
trimmed along the white margins and the difference in size ought not to
exceed one-tenth of a millimeter (one two-hundred-fiftieth of an inch).
Further, as different papers have different degrees of expansion, it is
necessary to use the same kind of paper for the two partial prints, and
it is best to take it from the same packet. It is also necessary to make
both prints in the same direction of the paper fibers, for the expansion
is different with and across the run of the paper.
One of the partial prints is transferred just as in the previous method.
The registration marks are also made as was previously described, only
the pencil marks must be placed exactly at the same points on the two
partial prints, which can be done by exact measurement. With this
process, also, the registration is not difficult in practice and the
careful worker will find that the impression in the transfer paper caused
by the first partial print, supplemented by the two lines on the edges,
is sufficient.
The inking up of the two partial prints is effected in the same way as
was outlined for the process with one print-plate.
Both variants of combination transfer offer operators with a little
dexterity a wide range of possibilities. By suitable treatment of the
partial prints the tone gradations can be controlled at will. The
resultant transfer will be softer or harder, as the shadow or the high
light print predominates; it is possible to omit certain portions in
either of the prints or subsequently print in more deeply any parts
which need special strengthening; the two prints may also be executed
in different shades of ink, with suitable discretion, and double tones
thus obtained. It is also possible to print in clouds from a separate
negative. Combination transfer is also well suited for polychrome
transfers, since it renders possible the overlaying of a delicate black
impression with different color tones. Again, since all the possibilities
of control offered by the bromoil process are available, an almost
unlimited new field of activity is given by combination transfer.
Finally, there is still another field in which the combination transfer
allows remarkable effects. If one has a negative with excessive
contrasts, as for instance, a dark arch with a vista of a sunny
landscape, a satisfactory print can be made without difficulty by means
of combination transfer. One partial print should be so made that it
reproduces as correctly as possible the details of the dark part of
the negative, in this case the arch, irrespective of the fact that the
sunny landscape will be partly underexposed. Another partial print is
then exposed for the sunny landscape, when naturally the details of the
arch are completely lost. One may even go further still, since the two
partial prints may be prepared from two negatives taken from the same
standpoint, the one being exposed for the high lights and the other for
the shadows. A combination transfer, correctly executed from two such
partial prints, gives a result in which both the darker and the lighter
parts of the negative are reproduced in suitable tone values. It may also
be mentioned that multiple transfer renders it possible to apply plenty
of ink to calendered and, therefore, non-absorbent papers, and thus
permits of the attainment of deep shadows, full of detail, on such papers.
In the various kinds of multiple transfer here outlined principles have
been introduced into the transfer process which have been used in the
gum-bichromate process and many graphic reproduction processes, in order
to produce wide ranges of tone values by several printings on one print.
Yet the means of attaining this end are novel, namely, either different
consistency of inks with one print-plate, or the use of two different
print-plates for one transfer.
In my first publications on such combination transfer processes, I
mentioned still a third possibility of obtaining the desired end, namely
the preparation of two partial transfers from one print by using two
different degrees of relief. The process first outlined, using different
consistencies of ink with one print, is, however, to be preferred to
the process in which two reliefs are used, wherefore the latter was not
further proceeded with.
The value of the transfer process has been so increased by the methods
just outlined that it is capable of solving the most difficult
photographic problem, and by its aid even negatives can be printed, which
cannot be satisfactorily rendered even in bromoil. While hitherto the
transfer process was only an offshoot of the bromoil process it is, since
the introduction of combination transfer, at least as valuable and in
many cases even surpasses it.