IMPROVEMENTS IN SUPPORTS TO BE USED IN PLACE OF GLASS FOR SUPPORTING PHOTOGRAPHIC FILMS, AND PROAL
Year: 1881

page_text: LETTERS PATENT to Alfred Pumphrey, of Birmingham, in the County of
Warwick, Manufacturer, for an Invention of "IMPROVEMENTS IN SUPPORTS TO
BE USED IN PLACE OF GLASS FOR SUPPORTING PHOTOGRAPHIC FILMS, AND
PROVISIONAL SPECIFICATION left by the said Alfred Pumphrey at the
Office of the Commissioners of Patents on the 9th April 1881.
ALFRED PUMPHREY, of Birmingham, in the County of Warwick, Manufacturer.
"IMPROVEMENTS IN SUPPORTS TO BE USED IN PLACE OF GLASS FOR SUPPORTING
PHOTOGRAPHIC FILMS, AND IN PHOTOGRAPHIC CAMERAS FOR EXPOSING PHOTO-
GRAPHIC FILMS."
The first part of my Invention consists of the method herein after described of
preparing supports for photographic films, by which method of preparation the
sensitive photographic film may be removed from the sheet of glass on which it
has been prepared, either before it is exposed in the camera or after a negative
picture has been produced upon it.
The second part of my Invention consists of the improvements herein after
described in photographic cameras, which said improvements are especially
applicable to cameras to be used with photographic films prepared according to the
first part of my Invention, but are also applicable to cameras in which other
photographic films are used.
By the use of my improvements, the plates of glass which, usually constitute the
permanent support of photographic films are almost wholly dispensed with
and the inconvenience both of the bulk and weight of the said glass plates got
rid of.
In preparing a support for a photographic film according to my Invention, I
proceed as follows:-I take ordinary uniodized collodion and coat a glass plate or
other flat smooth surface with the same. When the film has set or partly set, I
remove a portion of the collodion along each edge of the plate from one eighth of
an inch to a quarter of an inch in breadth so as to uncover the glass. I next take

page_text: a solution of gelatine of about thirty grains of gelatine to a liquid ounce of water,
and for each ten square inches of the plate to be covered I measure one drachm of
the solution, which must be sufficiently warmed to cause it to run freely.
Immediately before using the gelatine solution, I add to it a solution of chrome
alum in the proportion of two or three drops of the chrome alum solution to each
drachm of the gelatine solution. The solution of chrome alum I employ is made by
dissolving sixty grains of chrome alum in one ounce of water.
.
The collodionized glass plate is placed upon a carefully bevelled support and the
gelatine and chrome alum mixture poured thereon so as to cover both the
collodionized portion of the glass plate as well as the marginal portions from which
the collodion has been removed. The gelatine will not afterwards swell much
when placed in water or other liquid. Other methods of causing the gelatine to
set or contract, such as mixing it with bichromate of potash and exposing it to the
light, or placing it in a solution of alum may be employed. Although I prefer the
addition to the gelatine solution of chrome alum or bichromate of potash or the use
of common alum, yet the use of these materials may be dispensed with.
This compound film of gelatine and collodion supported on glass or other material
is allowed to dry either spontaneously or by the application of a gentle heat.
When the film is quite dry I spread upon it either gelatine emulsion or collodion
emulsion in the manner well understood in the preparation of dry photographic
plates. Or I spread collodion containing iodides or bromides, and the collodion is
made sensitive to light by dipping it into a solution of nitrate of silver and the
photographic process is completed in the ordinary way. When the film is dry I
cut through the edge of the collodion and it comes away with the photograph, be it
negative or positive, and is strong enough for most purposes. Or in the case of
dry processes the film can be removed before the exposure in the camera, and the
processes of developement and fixing the image conducted without the glass support
in the ordinary methods of operating.
Or in preparing the films by the gelatine process I coat the plate with collodion
and strip the edges as above described, and upon the coating of collodion I pour the
sensitive compound of gelatine and bromide of silver, making it lap over the
collodion, but I prefer to put a separate coating, as before described, as giving a
better thickness of film.
After
My improvements in photographic cameras consist in employing a series of
frames holding the sensitive films. These frames are so mounted on an axis that
by turning the axis by an external handle any one of the films may be brought
opposite the lens and into a plane at right angles to the axis of the lens.
exposure to light the film is carried by the motion of the handle into a dark part
of the camera, and another film is brought into the proper position to receive the
luminous image formed by the lens. A registering apparatus shows the particular
film that is being exposed.
In cameras for exposing large films the films are contained in a portfolio, and
the opposite sides of the camera are provided with sleeves through which the
operator introduces his hands for transferring the films from the portfolio and after
exposure returning them thereto. The dark slide is opened from the outside for
the exposure of the sensitive surface to the luminous image, and after the closing
of the sleeves through which the operator's hands had been introduced into the
camera.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Alfred Pumphrey in the Great Seal Patent Office on the
27th September 1881.
ALFRED PUMPHREY, of Birmingham, in the County of Warwick, Manufacturer.
"IMPROVEMENTS IN SUPPORTS TO BE USED IN PLACE OF GLASS FOR SUPPORTING
PHOTOGRAPHIC FILMS AND IN PHOTOGRAPHIC CAMERAS FOR EXPOSING PHOTO-
GRAPHIC FILMS."
The first part of my Invention consists of the method herein after described of
preparing supports for photographic films, by which method of preparation the
sensitive photographic film may be removed from the sheet of glass on which it
has been prepared, either before it is exposed in the camera obscura or after a
negative picture has been produced upon it.
The second part of my Invention consists of the improvements herein after
described in photographic cameras, which said improvements are especially
applicable to cameras to be used with photographic films prepared according to the
first part of my Invention, but are also applicable to cameras in which other
photographic films are used.
By the use of my improvements the plates of glass which usually constitute the
permanent, support of photographic films are almost wholly dispensed with,
and the inconvenience both of the bulk and weight of the said glass plates got
rid of.
In preparing a support for a photographic film according to my Invention, I
proceed as follows:-I take ordinary uniodized collodion and coat a glass plate or
other flat smooth surface with the same. When the film has set, or partly set, I remove
a portion of the collodion along each edge of the plate, the removed portion being
from one eighth of an inch to a quarter of an inch in breadth, so as to uncover
the marginal portions of the glass plate or other surface. I next take a solution
of gelatine of about thirty grains of gelatine to a liquid ounce of water, and for
each ten square inches of the plate to be covered I measure one and a half drachms
of the solution which must be sufficiently warmed to cause it to run freely.
Immediately before using the gelatine solution I add to it a solution of chrome
alum, in the proportion of two or three drops of the chrome alum solution to each
drachin of the gelatine solution. The solution of chrome alum I employ is made
by dissolving sixty grains of chrome alum in one ounce of water.
The collodionized glass plate is placed upon a carefully levelled support and the
warm gelatine and chrome alum mixture poured thereon, so as to cover both the
collodionized portion of the glass plate or surface and the marginal portions from
which the collodion has been removed. The gelatine in consequence of the
addition of the chrome alum will not swell much when placed in water or other
liquid. Other methods of causing the gelatine to set or contract, such as mixing it
with bichromate of potash and exposing it to the light, or placing it in a solution
of ordinary alum may be employed. Although I prefer the addition to the gelatine
solution of chrome alum, or bichromate of potash, or the use of common alum, yet
the use of these materials may be dispensed with.
This compound film of gelatine and collodion supported on glass or other material
is allowed to dry either spontaneously or by the application of a gentle heat.
When the film is quite dry I spread upon it either gelatine emulsion or collodion
emulsion, in the manner well understood in the preparation of dry photographic.
plates. Or instead of spreading upon the film sensitive gelatine or collodion
emulsion, I spread collodion containing iodides or bromides, and the iodized or
bromized collodion film is made sensitive to light by dipping the compound film
into a solution of nitrate of silver, and the photographic process is completed in
the ordinary way by exposing the compound film to the luminous image of the
camera developing the latent image by a reducing agent and fixing and washing
the picture produced. When the film is dry I cut through the edge of the

page_text: collodion, when the compound film with the picture upon it may be readily stripped
from the glass or other surface.
The compound film carrying the picture is strong enough for printing from and
for most purposes. Or in the case of dry processes, that is, when the sensitive film
is to be exposed to light on a dry plate, the sensitive film can be removed before
the exposure in the camera and the processes of development, and fixing the
image conducted without the glass support used in the ordinary methods of
operating.
Or in preparing the films by the gelative process I coat the plate with collodion
and strip the edges, as before described; and upon the coating of collodion I pour
the sensitive compound of gelatine and bromide of silver, making it lap over the
collodion, but I prefer to put on the plate a separate "or second thin coating of
gelatine before pouring on the gelatine emulsion as giving a better thickness of film.
When the film is detached from the glass or other surface, either before exposure
to light in the camera or otherwise, or after exposure to light and before develop-
ment, I prefer to support it during development and fixing on a sheet of paper.
For this purpose I coat one side of the sheet of paper and the back or collodionised
side of the film with a solution of india rubber in mineral naphtha of the
consistence of cream. When the paper and film have become tacky by the
evaporation of the mineral naphtha the paper and film are placed together, and by
passing them between a pair of rolls or otherwise are pressed into close contact.
After the completion of the picture the paper may be removed from the film by
gently pulling them asunder, the separation taking place readily on the application
of a slight force. Or the separation may be facilitated by dipping the picture into
mineral naphtha, when the film is so loosened that it very readily leaves the paper.
The moist film requires to be stretched during its drying in order to preserve its
flatness. This is conveniently effected in the following manner:-The surface
moisture having been removed by sponge or blotting paper the film is placed upon
a flat deal or other board, and the edges secured to the board by pins. In order to
do this the more quickly and regularly I prefer to employ ordinary dress pins,
fixed a short distance apart by soldering to strips of tin plate or sheet brass.
Twelve or more pins may be fixed to one strip of metal. By the use of these
groups of pins the film may be rapidly fixed on the drying board, and a whole
group passed through the edge of the film by one gentle blow of a hammer.
•
Figure 1 of the accompanying Drawing represents one of these groups of pins;
and Figure 2 represents two edges of a film fixed down for drying; a is the board;
b is the film; and c, d, groups of pins securing two edges of the film b to the board.
Although I have only described my Invention with reference to films exposed to
the action of light in the camera obscura, yet I wish it to be understood that films
made according to my Invention inay be employed for the production of photo-
graphs both negative and positive by the photographic process commonly called
photographic printing.
It will be understood that those stages of the process in which materials sensitive
to light are not employed may be conducted in daylight, but that those stages of
-the process in which gelatine or collodion emulsion is employed, or in which a film
of iodized or bromized collodion made sensitive to light by immersion in a solution
of nitrate of silver is employed, must be conducted in a room illuminated by
non-actinic light.
;
My improvements in photographic cameras consist in employing a series of frames
holding the sensitive films. One edge of each frame is hinged or connected to an
endless band passing over rollers, so that by turning one of the said rollers by an
external handle, any one of the films may be brought opposite the lens and into a
plane at right angles to the axis of the lens. After exposure to light the film is
carried by the motion of the handle into a dark part of the camera, and another
film is brought into the proper position to receive the luminous image formed
by the lens.
A registering apparatus shows the particular film that is being
-exposed.

page_text: Figure 3 of the accompanying Drawing illustrates this part of my Invention.
The films supported in frames are marked e; f is the lens of the camera.
A ground glass for focussing is fixed in one of the frames e, and can be brought
when required into a vertical position opposite the lens f. The image can be
examined by opening the door g; h, i, are dark and opaque flaps or screens which
can be raised and lowered by the handles h², 2. The handle gives motion to the
upper roller, and by turning the said handle in the proper direction and through
the required angle any desired film may be brought into a vertical position from
the unexposed films at the back part of the camera, and after exposure turned face
downwards in the front part of the camera. The size of the upper roller is such
that a quarter rotation turns down a film that has been exposed and brings another
into position for exposure. When the films are about to be moved the screens h, i,
are raised by their handles. The required film being brought into a vertical
position opposite the lens f, the screens h, i, are turned down and both the
unexposed and exposed films at the back and front of the camera respectively are
protected from light. The upper edge of the frame carrying the film which is
being exposed to the luminous image is supported in the proper position by the
stop l, on the rod m. The stop can be turned aside and returned to the position
shown by the handle n. A spring stop p engaging with pins or studs r, r, on the
disc q, on the axis of the upper roller determines the correct position of the lower
edge of the frame carrying the film being exposed. The pins r, r, engage with the
teeth of the wheel 8, the said teeth being marked with consecutive numbers as
represented; t is a fixed finger or pointer which indicates by the tooth to which
it points which of the films is under exposure.
l
The mechanism for fixing the lower edge of the frame and for indicating the
film under exposure is outside the camera.
Having now described the nature of my Invention, and the manner in which
the same is to be performed, I wish it to be understood that I claim as my
Invention,-
First. The method herein before described of preparing supports to be used in
place of glass for supporting photographic films, that is to say, by pouring upon a
sheet of glass or other flat surface plain or uniodized collodion, allowing the
collodion to set, removing the marginal portions of the collodion film, and pouring
over the collodion film and the marginal portions of the glass or surface from
which the collodion film has been removed a solution of gelatine either with or
without chrome alum or other hardening material, upon which compound film
when dry, the gelatine, or collodion emulsion is poured or other vehicle either
containing the silver compound sensitive to light or charged with the salt, which
in contact with a solution of nitrate of silver will produce a surface sensitive to
light, substantially as herein described.
Secondly. The parts of the photographic camera represented in Figure 3 of the
accompanying Drawing, marked respectively h, h², i, i², l, m, n, p, q, r. 8, and t,
that is to say, the flaps for covering the unexposed and exposed films or plates, the
stops for fixing the position of the frame carrying the film being exposed, and the
indicating mechanism for showing what particular film or plate is being exposed.
In witness whereof, I, the said Alfred Pumphrey, have hereunto set my hand
and seal, this Twenty-second day of September, in the year of our Lord
One thousand eight hundred and eighty one.
Witness,
GEORGE SHAW.
ALFRED PUMPHREY. (L.S.)