Dry plates, ranging in rapidity from one-tenth to one-twentieth the
time necessary for a wet collodion plate, are now commonly used in
the studios of this country. Of course, plates of such extreme
sensitiveness require great care in handling, and absolute freedom
from any umpremeditated exposure to white light is necessary to
their successful use.
It is therefore necessary that the dark room should be remodelled to
suit the requirements necessary to the successful handling of such
extremely rapid plates, and in this connection it is proposed to
describe the necessary changes and alterations.
Any ordinary dark room may with little expense be fitted for dry
plate work. First see that every chink or crevice which might admit
white light is stopped or [p049] filled up, then fit the door or
doors so that they will shut tight and remain closed.
For convenience of access to the room while work is proceeding, and
for greater safety, it is well to erect a small porch or ante-room
at each door, the entrance to which should be at right angles with
the dark room door. The door to this porch and the dark room door
should be fitted with springs to keep them closed. With this
arrangement one can have access to the dark room at any time by
closing one door before opening the other.
If the dark room is lighted by a window, it should be glazed with
dark red orange glass, and if the exposure is toward the sun, it
should be shaded with a green or ruby colored shade on a spring
roller. If the sun never shines in the window, the shade is not
necessary.
If the room is lighted by artificial light, the best way is to cut
an opening in the wall or partition at the most convenient place,
make a frame to fit or cover this opening, that will raise or slide,
glaze it with red orange glass. On a shelf outside the opening place
your gas-burner or lamp, with a large reflector behind, so as to
reflect all the light through the glass into the room. If gas is
used on the outside an argand burner will be the best, with a common
white glass chimney for ordinary work, but for the most sensitive
plates a light green or thin ruby chimney will be absolutely safe.
If a kerosene lamp is used, the common white chimney with full flame
will be safe; and being outside, the room will not be heated by its
flame, nor rendered offensive by its smoke and odor.
In front of the window or of the artificial light, [p050] erect a
shelf or place a small table with a level top, which will support
the developing dishes and bottles of developing solution, and on
which the work of development may be carried on.
If the room is so situated that neither window nor gas may be used
in the manner suggested, then procure Carbutt's Developing Lantern,
which is a most convenient lantern, not only for developing, but for
other purposes. See figure.
The dark room should be supplied with running water, and the more
generous the supply, the better, as a dry plate requires much
washing, and a large stream will do the work much quicker than a
small one.
[Illustration: WASHING BOX.]
In many instances, however, where running water may not be had, the
washing box may be used with advantage. If running water is used, be
careful not to use too much pressure; by attaching a rubber hose to
the faucet and passing it over a nail or hook above, the pressure
may be reduced so that a full but gentle stream falls upon the
plate.
Safe closets should be provided to contain all sizes of plates; or
the new [p051] made by Anthony & Co., may be used instead, both
for unexposed and for exposed plates awaiting development.
[Illustration: NEGATIVE BOXES,]
[Illustration: JAPANNED IRON DEVELOPING TRAY,]
[Illustration: ANTHONY'S GLASS TRAYS,]
[Illustration: GLASS BOTTOM DRY PLATE DEVELOPING TRAYS.]
The dark room should be supplied with the necessary apparatus, such
as developing trays, which are of japanned tin, of glass or india
rubber; see cuts, JAPANNED IRON DEVELOPING TRAY, ANTHONY'S GLASS
TRAYS, or the patented article, the GLASS BOTTOM DRY PLATE
DEVELOPING TRAYS, [p052] and also the dishes to contain the
fixing solutions, which may be trays or upright, like silver-bath
dishes.
THE COMMON SENSE TRAY is a capital dish to contain the hypo and
clearing solutions and is not expensive, and can be had of all
sizes. All these dishes should be kept scrupulously clean when not
in use.
[Illustration: THE COMMON SENSE TRAY.]
[Illustration: TN: Graduate.]
There should be Graduates of the 16 oz. and the 8 oz. sizes, and
also a minim glass measuring up to [p053] one fluid ounce, also
one or more of Anthony's Combined Funnel and Filter, for filtering
the various solutions.
[Illustration: ANTHONY'S COMBINED FUNNEL AND FILTER.]
[Illustration: FOLDING NEGATIVE RACK.]
There should be glass-stoppered bottles for containing the
developing solutions, especially the pyro; also racks to hold the
plates while drying; one finely adjusted scale with apothecary
weights weighing to a 1/4 lb.; one camel's hair-brush, 3 inches
wide, for dusting the plates before [p054] putting them in the
holders for exposure, and also for removing sediment from the
surface of the film after fixing and washing.
[Illustration: CAMEL'S HAIR DUSTERS.]
Thus fitted and furnished, the dark room is ready and well adapted
for the most difficult dry plate work, and we will now proceed to
the consideration of the