This paper is prepared with a sensitive surface, similar to the dry
plates commonly used, and must be handled with the same care and
subject to the same conditions of light; consequently the printing
must be done by artificial light only.
The paper being cut to the sizes desired, should be kept in a
light-tight box, and in a dark room. When about to print, place the
negative in a printing frame in the same manner as for silver
printing, lay the paper with the gelatine surface down upon the
negative, place a cloth pad upon the paper, then press the frame
back firmly down to secure even contact of the paper with the
negative.
All this should be done in a dark room by the aid of a non-actinic
light, and for this purpose Anthony's Climax Dark-Room Lantern,
Patented, as shown in the following cut, [p194] would seem to
fulfil every requirement. A more expensive, but very convenient
instrument, however, is CARBUTT'S MULTUM IN PARVO DRY PLATE
LANTERN, [p195] which has proved to be most suitable for this
particular purpose.
[Illustration: TN: Anthony's Climax Dark-Room Lantern.]
[Illustration: CARBUTT'S MULTUM IN PARVO DRY PLATE LANTERN]
The paper having been placed in the printing frame, the frame is set
up, as seen in the [TN: following] cut, and the door in the side of
the lantern opened, which permits the white light from the lamp to
fall upon the surface of the negative; an exposure of from 5 to 10
seconds is all that will be necessary, even in case the negative is
quite dense; a thin negative will print with less exposure, say 3 to
5 seconds, at a distance of from 12 to 15 inches from the light.
[Illustration: Lantern arranged for making positives by contact.]
The paper when taken from the frame presents no change of surface,
and must be developed in the same manner as a dry plate, to bring
out the picture.
Previous to developing, lay the paper in a dish of clean water for a
short time, and then transfer it to the developing tray. [p196]
The developing is done by the ferrous oxalate process. Solutions as
follows:
Saturated solution oxalate potash 3 oz.
Saturated " photosulphate iron 1/2 oz.
Bromide " (12 grains bromide of
ammonium to 1 oz. water) 1/4 dram.
Saturated solution tartaric acid 2 drops.
This developer can be used several times successively until it
becomes turbid. The best way is to first print and develop one
print, to ascertain the proper time of exposure. Then make as many
prints as are necessary, and develop them all together in a dish
large enough, and with sufficient of the solution to cover them
nicely. Observe carefully not to develop too far, as the resulting
prints will be too dark. When the prints are developed, wash them
well and fix them in a new solution of
Hyposulphite of soda 1 ounce.
Water. 8 "
The fixing will require from five to ten minutes; then wash and pass
the prints through a clearing solution consisting of
Alum 2 ounces.
Water 6 "
then wash again and hang up, or place between clean blotters to dry.
It is necessary that the hands be free from any trace of silver or
hypo when handling these prints while developing, or afterwards when
wet, to avoid stains, etc. The same precautions as to the relative
proportions of the oxalate solution and the iron are to be observed
as for the development of negatives. [p197]