The other "lost" posting....
>From Photographic Amusements (1937):
LUMINOUS PHOTOGRAPHS
There are several different ways of making these. Obtain some Balmain's
luminous paint, and coat a piece of cardboard with it. Place this in the
dark until it is no longer luminous; then place it behind a glass
transparency and expose to daylight or, if at night, burn a small piece of
magnesium wire. Return to the dark, remove the transparency, and a luminous
photograph is obtained on the prepared card. A simple plan is merely to
expose a piece of the prepared cardboard to the light and place it behind a
transparency; then retire to a darkened room. The luminous paint, showing
through it, will have a very pretty effect. If no glass transparency is at
hand, a silver print can be used, if previously oiled and rendered
translucent by vaseline or any other means.
>From Cassell (1911):
LUMINOUS PHOTOGRAPHS
Photographs which appear luminous or phosphorescent at night. They may be
prepared in several ways. The simplest is that of making a positive
transparency-as, for example, a lantern slide-varnishing the film side, and
coating with luminous (Balmain's) paint. When dry, the transparency is
backed with thin wood or cardboard, with a ring for hanging, and the whole
bound together with strips of gummed paper or cloth. If exposed to light
during the day the picture will appear luminous at night. Another plan is to
spread a thin coating of glue upon cardboard and sprinkle with powdered
barium or calcium sulphide, or to coat with Balmain's paint. A print is then
made upon thin sensitive paper which, after finishing In the usual way, is
made
transparent with castor oil, the excess blotted off, and the print attached
to the. treated cardboard with thin glue or strong paste, and dried by heat.
A method popular in Germany is to coat a piece of thin transparent celluloid
with the following :-
Gelatine 436 grs. 100 g.
Potas. bichromate 48 grs. 11 g.
Calcium suiphide . 0.5 oz. 55 g.
Water 10 oz. 1,000 ccs.
The gelatine is soaked in the water, melted by heat, the other ingredients
added and dissolved, and the mixture filtered through cotton-wool. When
dry, the coated celluloid may be printed upon from a positive through the
celluloid film, and the image developed in warm water in the same way as in
the carbon process, a print being obtained which shows as a negative by
transmitted light. This needs to be backed with black velvet or black paper,
when it will appear as an ordinary black-and-white positive by daylight, and
as a luminous or phosphorescent picture by night.
>From Henley's Twentieth Century Formulas, Processes and Trade Secrets
(1948):
LUMINOUS PAINTS.
The illuminating power of the phosphorescent masses obtained by heating
strontium thiosulphate or barium thiosulphate is considerably increased by
the addition, before heating, of small quantities of the nitrates of
uranium, bismuth, or thorium. Added to calcium thiosulphate, these nitrates
do not heighten the luminosity or phosphorescence. The product from
strontium thiosulphate is more luminous than that of the barium compound.
Among the best luminous paints are the fo1lowing:
I.-Lennord's.-One hundred parts, by weight, of strontium carbonate; 100
parts, by weight, of sulphur; 0.5 parts, by weight, of potassium chloride;
0.5 parts, by weight, of sodium chloride; 0.4 parts, by weight, of manganese
chloride. The materials are heated for three-quarters of an hour to one
hour, to about 2,372 deg. F. The product gives a violet light,
II.-Mourel's.-One hundred parts, by weight, of strontium carbonate; 30
parta, by weight, of sulphur; 2 parts. by weight, of sodium carbonate; 0.5
parts, by weight, of sodium chloride: 0.2 parts, by weight, of manganese
sulphate. The method of treatment is the same as in the first, the
phosphorescence deep yellow.
III.-Vanono's.-Sixty parts, by weight, of strontium thiosulphate; 12 parts,
by weight, of a 0.5 per cent acidified alcoholic solution of bismuth
nitrate; 6 parts, by weight, of a 0.5 per cent alcoholic solution of
uranium nitrate. The materials are mixed, dried, brought gradually to a
temperature of 2,372 deg. F., and heated for about an hour. The phosphoresce
is emerald green.
IV.__Balmain's.-Twenty parts, by weight, of calcium oxide (burnt lime), free
from iron; 6 parts, by weight, of sulphur; 2 parts, by weight, of starch; 1
part, by weight, of a 0.5 per cent solution of bismuth nitrate; 0.15 parts,
by weight, of potassium chloride; 0.15 parts, by weight, of sodium chloride.
The materials are mixed, dried, and heated to 1,300 deg. C. (2,372 deg.
F.). The product gives a vio-let light.
To make these phosphorescent substances effective, they are exposed for a
time to direct sunlight; or a mercury lamp may be used. Powerful
incandescent gas light also does well, but requires more time.
Another plan might be to use luminous pigment for gum printing?
Liam
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