Improved Method of Producing Photographic Pictures.
Year: 1898

page_text: Improved Method of Producing Photographic Pictures.
A communication from ENRIQUE GOLDSCHMIDT, of 5, Knobelsdorffstrasse, Charlot-
tenburg, near Berlin, in the Empire of Germany, Merchant.
I, ALFRED JULIUS BOULT, of 111, Hatton Garden, in the County of Middlesex,
Chartered Patent Agent, do hereby declare the nature of this invention to be as
follows:-
--
The process forming the object of this invention differs from the rapid pro-
cesses usually employed by the fact, that the sensitive plate first obtained is not
delivered as the product, but that, as in the usual ordinary photographic process,
the sensitive plate serves as the negative, from which the positive pictures are
made. In the former process the saving of time in producing a photograph is
attained by coating the back of the wet (collodium) negative, if this is used, with
black varnish in order to produce by the contrast between the blackness and the
grey-white silver picture the impression of a positive. If a dry-plate negative is
employed, the whites of the picture are obtained by mercury treatment where
the glass plate may be substituted by a black japanned sheet.
There is therefore peculiar to both processes, that with each operation only one
view is produced, while in the new process hereinafter described, as in the ordinary
photographic processes, from the existing sensitive plate any desired number of
copies may be made.
The rapidity of the new process, which is considerably superior to that of the
older processes, is attained in the following manner:-
In photographic practice it is usual to obtain from thin weak negatives a strong
copy by copying under silk-paper or, when the negative is very thin, under
yellow glass or yellow waxed taffetas or the like. Upon this principle the new
process is based. The photograph is taken and the view is developed by means
of a strong developer, but only to such an extent, that, when examined all the
details are visible. The plate is then very rapidly washed and whilst still wet,
and in its unfixed condition a sheet of bromide of silver paper, or a bromide of
silver postcard or other very sensitive copying paper is placed and squeezed upon
it by means of a rubber squeegee and then, as in the usual copying process, in
producing a so-called contact-copy, exposed to the light of a lamp for a few
seconds. The paper is then lifted off and developed in a suitable developer and
can be fixed and washed afterwards.
By omitting the fixing of the photographic plate, the yellow bromide of silver
is preserved in the film and acts as the above mentioned yellow veil in copying the
thin negative, and by this means a clear strong picture is obtained from the latter,
notwithstanding its thinness which renders it completely unfit for use in the
ordinary wav.

page_text: By proceeding in the above described manner all the time is saved as will be
easily understood, which was formerly necessary for the washing of the negative,
fixing it and for thoroughly washing it again."
The application of the bromide of silver paper upon the non-fixed negative
whilst wet is done not only in order to save time, but also to obtain, what in the
dark can be judged of with difficulty, an intimate contact between the film and
the bromide of silver paper. To attain the latter still more rapidly and com-
pletely the bromide paper prior to its application may also be thoroughly
moistened in water under the tap or by immersing it in a bowl of water so that
on application of the paper to the plate there is only water between the two layers
which is pressing the two together by means of a rubber-squeegee.
In this way air-bubbles are avoided and the formation of spots resulting from
the refraction of the light in copying is prevented.
The process above described allows of the production within less than four
minutes as numerous tests have proved or even within less than three minutes
after taking the photograph, photographic positive-pictures either on paper or
on other material and of producing moreover within a comparatively shorter time
from the existing negative any desired number of copies.
In the last case it was found from time to time that a certain amount of
developer owing to the rapid washing of the plate was still present though in a
dilute condition in the negative film, and under the action of the light necessary
for copying it gradually it veiled the negative so that when a larger number of
copies were to be made, the last were not of so good a quality as those first made.
This drawback is avoided by immersing the plate just developed, after having
been rinsed for a few seconds, for some seconds in an aqueous solution of bromide
of potassium it being then again rinsed rapidly before printing. The solution of
bromide of potassium remaining owing to the very rapid rinsing in the layer acts
in the subsequent printing process not only not prejudicially, but contributes in
bromide of silver paper to the production of a picture rich in contrasts, and show-
ing considerable density whereby the decrease of power or loss of tone which always
takes place with bromide paper during drying is compensated.
Dated this 5th day of August 1898.
BOULT & WADE,
Agents for the Applicant.
A communication from ENRIQUE GOLDSCHMIDT, of 5, Knobelsdorffstrasse, Charlot-
tenburg, near Berlin, in the Empire of Germany, Merchant.
I, ALFRED JULIUS BOULT, of 111, Hatton Garden, in the County of Middlesex,
Chartered Patent Agent, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
The process forming the object of this invention differs from the rapid pro-
cesses usually employed by the fact, that the sensitive plate first obtained is not
delivered as the product, but that, as in the usual ordinary photographic process,
the sensitive plate serves as the negative, from which the positive pictures are
made. In the former process the saving of time in producing a photograph is
attained by coating the back of the wet (collodium) negative, if this is used, with
black varnish in order to produce by the contrast between the blackness and the

page_text: grey-white silver picture the impression of a positive. If a dry-plate negative is
employed, the whites of the picture are obtained by mercury treatment where
in place of the glass plate a black japanned sheet may be substituted.
There is therefore peculiar to both processes, that with each operation only one
view is produced, while in the new process hereinafter described, as in the ordinary
photographic processes any desired number of copies may be made from the exist-
ing sensitive plate.
The rapidity of the new process, which is considerably superior to that of the
older processes, is attained in the following manner.
In photographic practice it is usual to obtain a strong copy from thin weak
negatives by copying under silk-paper or, when the negative is very thin, under
yellow glass or yellow waxed taffetas or the like. Upon this principle the new
process is based. The photograph is taken and the view is developed by means
of a strong developer, but only to such an extent, that, when examined all the
details are visible. The plate is then very rapidly washed and whilst still wet,
and in its unfixed condition, a sheet of bromide of silver paper, or a bromide of
silver postcard or other very sensitive copying paper placed and squeezed upon
it by means of a rubber squeegee and then, as in the usual copying process, in
producing a so-called contact-copy, exposed to the light of a lamp for a few
seconds. The paper is then lifted off and developed in a suitable developer and
can be fixed and washed afterwards.
By omitting the fixing of the photographic plate, the yellow bromide of silver
is preserved in the film and acts as the above mentioned yellow veil in copying the
thin negative, and by this means a clear strong picture is obtained from the latter,
notwithstanding its thinness which renders it completely unfit for use in the
ordinary way.
By proceeding in the above described manner all the time is saved, as will be
easily understood, which was formerly necessary for the washing of the negative,
fixing it and for thoroughly washing it again.
The application of the bromide of silver paper upon the non-fixed negative
whilst wet is done not only in order to save time, but also to obtain, what in the
dark can be judged of with difficulty, an intimate contact between the film and
the bromide of silver paper. To attain the latter still more rapidly and com-
pletely the bromide paper prior to its application may also be thoroughly
moistened in water under the tap or by immersing it in a bowl of water, so that
on application of the paper to the plate there is only water between the two layers
which is expelled by pressing the two together by means of a rubber-squeegee.
In this way air-bubbles are avoided and the formation of spots resulting from
the refraction of the light in copying prevented.
The process above described allows of the production within less than four
minutes, as numerous tests have proved, or even within less than three minutes
after taking the photograph, photographic positive-pictures either on paper or
on other material, and of producing moreover within a comparatively shorter time
from the existing negative any desired number of copies.
In the last case it was found from time to time that a certain amount of
developer owing to the rapid washing of the plate was still present though in a
dilute condition in the negative film, and under the action of the light necessary
for copying, it gradually veiled the negative so that when a larger number of
copies were to be made, the last were not of so good a quality as those first made.
This drawback is avoided by immersing the plate just developed, after having
been rinsed for a few seconds, for some seconds in an aqueous solution of bromide
of potassium it being then again rinsed rapidly before printing. The solution of
bromide of potassium remaining owing to the very rapid rinsing in the layer acts
in the subsequent printing process not only not prejudicially, but contributes in
bromide of silver paper to the production of a picture rich in contrasts, and show-
ing considerable density whereby the decrease of power or loss of tone which always
takes place with bromide paper during drying is compensated.

page_text: Having now particularly described and ascertained the nature of the said inven-
tion, as communicated to me by my foreign correspondents, and in what manner
the same is to be performed, I declare that what I claim is:-
-
1. A contact process for producing photographic pictures in which a sensitized
sheet is brought in contact with and exposed beneath an under-developed and
washed but unfixed negative in a wet state substantially as described.
2. A photographic picture produced substantially as and in the manner
described.
13
1
1000