Improvements in and relating to Photographic Cameras.
Year: 1894

page_text: Date of Application, 22nd June, 1894
PROVISIONAL SPECIFICATION.
Improvements in and relating to Photographic Cameras.
I WILLIAM ARTHUR DAWKINS Brass-founder of Speedwell Works Warston
Parade East Warston Lane, Birmingham in the County of Warwigk do hereby
declare the nature of this invention to be as follows:-
This invention relates to the class of photographic cameras technically known
as the detachable camera or the hand camera, namely cameras used more especially
by amateurs, such cameras are usually provided with a dark chamber composed of
black linen, leather or such like compressible material secured to the upper end of
camera in such a manner that the bag can be pushed into the camera and enclosed
by means of a lid when not in use and when in use the bag can be expanded
outwards from the camera; the object of this old-style hag is to produce and
retain a dark chamber within which a number of sensitized plates are provided
ready to receive photographs; one of the series of sensitized plates is in the
position ready for exposure and the remainder of the plates are behind the first
plate; the operator after having obtained a photograph on the first plate, puts
his finger and thumb on the outer surface of the collapsible bag and lifts the
pictured plate from its front position and moves it to the rear position behind
the other plates thus exposing a fresh plate ready to receive a picture; this
old-style method has some disadvantages, because the collapsible bag is continually
taking fresh creases and thereby becoming worn out or imperfect; the operator
in lifting the plates becomes impatient (especially an amateur) and cannot
spontaneously select a part of the bag to grip with his finger and thumb over
the plate with the satisfactory knowledge that when the plate is lifted the bag
will extend upwards sufficiently to enable the operator to lift the front picture
plate clean over the top edges of the sensitized plates so as to lower the picture
plate at the back of the blank plates; several attempts have to be made in the
lifting of the picture plate; it will be apparent that from the causes hereinbefore
set forth, the expandable bag is very quickly creased, worn and otherwise injured,
rendering it no longer an excluder of light, and consequently a camera made with
such a collapsible bag cannot produce perfect pictures; the pictures are foggy
and spotted on account of rays of light penetrating through the imperfect bag.
My invention relates to the collapsible bag. Instead of making a pocket-shaped
flabby bag, I make my dark chamber by means of leather, linen, vulcanised linen,
vegetable leather, or any suitable material such as that used in the old-style of
bag or such as would be more suitable for making a dark chamber, and I make
the chamber in the form of a pleated accordion; the pleats may be at the sides
only or at the ends only, or at both the sides and the ends; the pleated accordion
chamber has definite dimensions, instead of the sides and the ends collapsing
and expanding to indefinite directions my accordion pleated chamber collapses
and expands each time within the same pleats, consequently there is an internal
chamber of definite dimensions corresponding to the camera chamber, that is to
say, when the width of removable sensitized plates is four inches I make the
internal length of my dark chamber about four and a quarter, more or less and
the internal width a little over the space occupied by the nest of plates, thus if
the nest of plates measured two inches across, the internal width of my dark
chamber would be about two and a quarter more or less; on the last layer of
the accordion pleats I secure a collapsible sheet or piece of material suitable
to take hold of by means of thumb and finger to remove the picture plate.

page_text: In using my improved accordion pleated dark chamber, such box-shaped
collapsed chamber would be lowered over the nest of sensitized plates and the
lid closed in the usual way to take the first picture. After the first picture had
been taken the picture plate could be taken hold of by means of the top collapsible
sheet, the operator would readily clip the top end of picture plate and lift it in
an upward direction under the collapsible top sheet, and such lifting action would
expand the accordion pleats to the required height, the height being regulated by
means of the pitch of the pleats; it will be readily understood that having lifted
the plate to a definite height it could be tilted between the fingers and thumb so as
to move the bottom edge of the raised plate within the open space or chamber
provided between the accordion pleats until the bottom edge of the lifted plate
reached the proper position to pass behind the sensitized plates.
The providing of an accordion plented dark chamber for the purpose described
constitutes my invention.
1 WILLIAM ARTHUR DAWKINS Brass-founder of Speedwell Works Warstone
Parade East Warstone Lane Birmingham in the County of Warwick do hereby
declare the nature of this invention and in what manner the same is to be
performed, to he particularly described and ascertained in and by the following
statement :-
This invention relates to the class of photographic cameras technically known as
the detective camera, or the hand camera, namely cameras used more especially by
amateurs, such cameras are usually provided with a dark chamber composed of
black linen, leather or such like compressible material secured to the upper end of
camera in such a manner that the bag can be pushed into the camera and enclosed
by means of a lid when not in use and when in use, the bag can be expanded
outwards from the camera.
The object of this old style bag is to produce and retain a dark chamber within
which a number of sensitized plates are provided ready to receive photographs.
One of the series of sensitized plates is in the position rendy for exposure, and
the remainder of the plates are behind the first plate; the operator after having
obtained a photograph on the first plate, puts his finger and thumb on the outer
surface of the collapsible bag and lifts the pictured plate from its front position
and moves it to the rear position behind the other plates, thus exposing a fresh
pinte ready to receive a picture: this old style method has some advantages,
because the collapsible bag is continually taking fresh creases and thereby
becoming worn out or imperfect: the operator in lifting the plates becomes
impatient (especially an amateur) and cannot spontaneously select a part of the
bag to grip with his finger and thumb over the plate with the satisfactory
knowledge that when the plate is lifted, the bag will extend upwards sufficiently
to enable the operator to lift the front picture plate clear over the top edges of the
sensitized plates so as to lower the picture plate at the back of the blank plates;
several attempts have to be made in the lifting of the picture plate; it will be
apparent that from the enuses hereinbefore set forth, the expandable bag is very
quickly creased, worn and otherwise injured, rendering it no longer an excluder of
light, and consequently a camera made with such a collapsible bag cannot produce
perfect pictures; the pictures are foggy and spotted on account of rays of light
penetrating through, the imperfect bag.
My invention relates to the collapsible bag, I make my dark chamber or
collapsible bag a by means of jenther, linen, vulcanised-linen, vegetable-leather, or

page_text: any suitable material such as that used in the old style of bag or such as would be
more suitable for making a dark chamber, and I make the chamber in the form of
a pleated accordion, the pleats b may be at the sides only or at the ends only, or at
both the sides and the ends; the pleated accordion chamber a has definite
dimensions, instead of the sides and the ends collapsing and expanding in indefinite
directions, my accordion pleated dark chamber a collapses and expands each time
within the same pleats consequently there is an internal chamber of definite
dimensions corresponding to the camera chamber c that is to say, when the width
of removable sensitized plates is four inches I make the internal length of my dark
chamber pleated bag a about four and a quarter inches, more or less, and the
internal width a little over the space occupied by the nest of plates, thus if the nest
of plates measured two inches across, the internal width of my dark chamber a
would be about two and a quarter inches more or less: On the last layer of the
accordion pleats I secure a collapsible sheet or piece of material & suitable to
hold by means of the thumb and finger as shewn at e.
1 will now describe the figures of the drawings.
C
Figure represents a front view of a broken-off top portion of sensitized
plate-frame when grasped between the thunb and finger for the purpose of moving
the plate and frame.
Figure 2 represents a sectional elevation of back part of camera with the
sensitized plate-frame about to be dropped behind the nest of plates; the accordion
pleats being expanded.
Figure 3 represents a broken off sectional elevation of back part of camera with
accordion pleats and top door closed.
In using my improved accordion pleated dark chamber a such box-shaped
collapsed chamber a would be lowered over the nest of sensitized plates and the
lid closed in the usual way to take the first picture. After the first picture had
been taken, the picture plate could be taken hold of by means of the top collapsible
sheet d the operator readily clipping the top end of picture plate g and lifting it in
an upward direction under the collapsible top sheet, and such lifting action would
expand the accordion pleats to the required height, the height being regulated by
means of the pitch of the pleats; it will be readily understood that having lifted
the plate to a definite height, it could be tilted between the finger and thumb, so
as to move the bottom edge of the raised plate within the space or chamber a
provided between the accordion pleats, until the bottom edge of the lifted plate
reached the proper position to pass behind the sensitized plates.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
clain is
The making of a photographic camera with a dark-chamber consisting of a
collapsible accordion pleated bag as illustrated and described for use
manner described.
Dated this 20th day of March 1895.
in the
ALFRED WILLIAM TURNER,
Cobden Buildings, Corporation Street, Birmingham,
Agent for the Applicant.
ALFRED WILLIAM TURNER,
Cobden Buildings, Corporation Street, Birmingham,
Agent for the Applicant.