IMPROVEMENTS IN APPARATUS FOR USE IN TRANSPORTING AND EXPOSING SENSITIZED PHOTOGRAPHIC PLATES OR FILMS
Year: 1883

page_text: LETTERS PATENT to John Edwin Atkinson of Greenwich in the County of
Kent for an Invention of IMPROVEMENTS IN APPARATUS FOR USE IN
TRANSPORTING AND EXPOSING SENSITIZED PHOTOGRAPHIC PLATES OR FILMS
PROVISIONAL SPECIFICATION left by the said John Edwin Atkinson at the
Office of the Commissioners of Patents on the 4th October 1883.
"IMPROVEMENTS
JOHN EDWIN ATKINSON of Greenwich in the County of Kent,
IN APPARATUS FOR USE IN TRANSPORTING AND EXPOSING SENSITIZED PHOTOGRAPHIC
PLATES OR FILMS."
My Invention relates both to indoor and outdoor photography and consists in
improved means or apparatus for holding and protecting sensitized dry plates or
films either for transit or storage and for enabling the plates or films to be readily
placed in position for exposure in the camera and removed therefrom after
exposure, in open daylight, whereby a number of such plates or films are rendered
more conveniently portable than in ordinary double backs, changing boxes, or other
costly and inconvenient apparatus as beretofore constructed.
My Invention consists in the employment of envelopes made of cardboard, papier
maché, or other light and cheap material in the form of a square or rectangular
frame constructed to carry one or two plates or films (preferably one plate or film
only) having an opening at front rather smaller than the plate or film to be
carried. This opening of the frame is closed by a sliding shutter preferably flexible
and sliding in grooves or otherwise and the plate or film is introduced at the back
of the envelope (when constructed to carry one plate or film) by being laid therein
face downwards and the envelope is merely closed at the back by four loose flaps
respectively attached to its four sides and merely folding down over one another or
by other suitable means whereby a light-tight closure is ensured.
The plates or films are carried preferably each in its own envelope and the
camera is provided with a back" being a receptacle or box which is adapted to fit
against the back of the camera and is hinged thereto or fitted in slides thereon so
[Price RI

page_text: as to be readily moved in and out of position to enable the operations of focussing
and exposing to be expeditiously performed. This box or receptacle is of a size to
exactly contain one envelope; it has an opening at front corresponding to that in
the envelope and a door at back at which the envelope is introduced and a slot at
one side to enable the slide or shutter of the envelope to be withdrawn.
The operation is as follows:-The envelope containing the plate is placed in the
box or receptacle, the projecting portion of the slide or shutter of the envelope
being passed through the slot in the side of the receptacle. After focussing the
picture in the usual way the "back" is placed in position for exposure, and the
shutter or slide of the envelope is drawn out through the slot in the "back." After
the exposure is terminated the shutter is pushed in and the envelope removed from
the "back" the exposed plate which is still contained therein being subsequently
developed at leisure.
The focussing screen is hinged to the camera and the hinges are so constructed
that the screen may be folded against the rear of the "back" in packing the
camera for transport.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Edwin Atkinson in the Patent Office on the 29th March
1884.
JOHN EDWIN ATKINSON, of Greenwich in the County of Kent "IMPROVEMENTS
IN APPARATUS FOR USE IN TRANSPORTING AND EXPOSING SENSITIZED PHOTOGRAPHIC
PLATES OR FILMS
"
My invention relates both to indoor and outdoor photography and consists in
improved means or apparatus for holding and protecting sensitized dry plates or
films either for transit or storage and for enabling the plates or films to be readily
placed in position for exposure in the camera and removed therefrom after
exposure, in open daylight, whereby a number of such plates or films are rendered
more conveniently portable than in ordinary double backs, changing boxes or other
costly and inconvenient, apparatus as heretofore constructed.
My invention consists in the employment of envelopes in the form of a
rectangular frame constructed to carry one or two plates or films (preferably one
plate or film only) having an opening at front closed by a sliding shutter sliding in
grooves or otherwise. The plate or film is introduced at the back of the envelope
(when constructed to carry one plate or film) by being laid therein face downwards
and the envelope is merely closed at the back by four loose flaps respectively
attached to its four sides and merely folding down over one another. Each plate
or film is carried in a separate envelope and the camera is provided with a "back"
which is adapted to fit against the rear of the camera body and works on hinges or
in slides so as to be readily moved in and out of position to enable the operations
of focussing and exposing to be expeditiously performed. This back is a receptacle
of a size to exactly contain one envelope; it has an opening at front corresponding
to that in the envelope, and a door at back at which the envelope is introduced and
a slot at one side to enable the slide or shutter of the envelope to be withdrawn.
DESCRIPTION OF DRAWINGS.
Figure 1 is a rear view of the camera "back" the shutter of the envelope
contained therein being drawn out for exposing: Figure 2 is a side view of a
portion of the camera the back being swung aside on its hinges, and the focussing
screen brought down for focussing the picture. Figure 3 is a plan of the same.
Figure 4 is a side view of the camera folded for transport. Figure 5 is a plan of
part of the same showing the hinges of the focussing screen made moveable to enable
the screen to fold between the back and the tail board. Figure 6 is a rear view of
an envelope open for the insertion of the plate or film. Figure 7 is a cross section
and Figure 8 a rear view of the same closed. Figure 9 is a face view of the
envelope with the shutter drawn out.
.
The envelope shown in figures 6, 7, 8 and 9 is adapted to carry one plate or film
and consists of a frame a having at the front an opening (see figure 9) rather smaller
than the plate or film to be carried and having grooves b to receive a sliding
shutter c which works through a slot in one end of the frame. The frame is made
of wood cardboard papier-maché or other light and cheap material and the shutter
is made of thin wood cardboard or other light and stiff material covered with silk
or other thin and durable fabrio the wood or other stiffening being creased cut or
scored transversely at c¹ c³ to enable the projecting end o³ of the shutter to bo
folded back as shown in dotted lines figure 8 when packed for transport. The
shutter is also creased at of o³ to enable it to bend when drawn out.
The frame a

page_text: is rebated at the back to receive the sensitized plate or film x and is provided with
four flaps d' d' d' d' of flexible light-proof material such as india-rubber coated
fabric cemented respectively to the four sides of the frame and adapted to be folded
down over one another in the order in which they are referred to whereby a
thoroughly light tight closure is obtained. These envelopes are in the nature of a
dark slide but from their construction are much lighter and more portable inasmuch
as a considerable number of them may be conveniently carried in a small bulk.
They differ moreover in the mode in which they are placed in position in the
camera.
For this purpose the camera back is constructed as shown in figures 1 to 5 and
consists of a frame e in which fits one of the envelopes above described which is
introduced flatwise by opening a door f forming the back of the receptacle e. This
door is shewn open in dotted lines in figure 3 but when opening this door the
back e would be in the closed position shown in figure 1. The frame e works on
hinges g attached to a frame k which may either be a permanent portion of the
camera body or may be detachable for a purpose explained hereafter. The door f
is hinged at h to the frame e and the opposite end of the frame e may have a slot i
in it through which the shutter o may be drawn out in which case the projecting
end or tab c of the envelope shutter would have to be first passed through said
slot in the act of placing the envelope in the frame e or preferably the end of the
frame e is cut away to the depth of the slot and the door carries a corresponding
filling piece f¹ which leaves the necessary slot for the passage of the shutter when
the door fis closed, the envelope being merely laid flatwise in the frame e.
The door carries a spring ; which when the envelope is in position and the door
shut presses against the back of the flaps of the envelope and holds the margin of
the plate or film close against the frame a of the envelope and at same time holds
the frame a of the envelope against its seat in the frame e as shown partly in
section in figure 3. The door may be secured by buttons l. The frame e works on
hinges gas before mentioned and fits light-tight against the frame k and may be
locked by end bolts m. This frame k is detachable being rebated to fit in the body
of the camera n and held in place by clasps o. The frame may be placed side
uppermost so as to bring the back e and the contained plate or film into any desired
position. By making the frame k detachable the invention may be readily applied
to any camera but the hinges g might be attached directly to the camera body if
preferred.
"
The focussing glass pis hinged to plates q which may be slid in staples r at the
top of the frame k to enable the screen to be folded against the rear of the "back"
or frame e when the camera is packed for transport as shown in figures 4 and 5.
In focussing, this screen takes the place of the frame e (which is thrown back on
its hinges as in figures 2 and 3) the ground glass screen then corresponding to the
plane occupied by the sensitized plate or film in said frame e when the latter is in
position for exposure.
.
The operation of using the above described apparatus is as follows :-'
The envelope
containing the plate is placed in the receptacle e the projecting portion of its slide
or shutter being either laid in or passed through the slot i in the end of the
frame e and the door f is closed. After focussing the picture in the usual way the
"back"
e is placed in position for exposure, and the shutter or slide c of the
envelope is drawn out through the slot & After the exposure is terminated
the shutter is pushed in and the envelope removed from the "back," the exposed
plate remaining in the envelope for subsequent development at leisure.
Having described the nature of the said Invention and the manner of performing
the same I declare that what I claim as the Invention to be protected by the
hereinbefore in part recited Letters Patent is:
1** An envelope for sensitized plates or films constructed of a frame closed at
back by overlapping flaps and provided with a dark shutter substantially as and for
the purpose described,
"

page_text: 2ndly. The construction of the "back" for a photographic camera of a frame or
receptacle adapted to receive an envelope of the kind herein specified and having
an opening at front corresponding to the opening in the envelope and a slot at the
side for drawing out the shutter of the envelope and a door at back at which to
introduce the envelope substantially as herein shown and described.
3rdly The combined employment in the manner and for the purpose herein
specified of a series of holders or envelopes for sensitized plates or films constructed
substantially as herein described, and of a camera "back" constructed substantially
as herein described to receive one such plate holder or envelope at a time and
enable the plate or film to be properly exposed by drawing out the shutter of the
envelope such camera "back" working on hinges or in slides substantially as
specified.
In Witness whereof I the said John Edwin Atkinson have to this my
Specification hereunto set my hand and seal this twenty sixth day of March,
A.D. 1884.
JOHN EDWIN ATKINSON (L.S.)
Witness:-
J. W. KENNARD
Clerk to A. M. & W. Clark
Patent Agents 53 Chancery Lane
London