Early Work In Photography
A Text-book For Beginners
Forfatter: W. Ethelbert Henry C. E., H. Snowden Ward
År: 1900
Forlag: Dawbarn and Ward, Limited
Sted: London
Udgave: 2
Sider: 103
UDK: IB 77.02/05 Hen
Illustrated with an actual negative and positive, and numerous
explanatory diagrams throughout the text
Søgning i bogen
Den bedste måde at søge i bogen er ved at downloade PDF'en og søge i den.
Derved får du fremhævet ordene visuelt direkte på billedet af siden.
Digitaliseret bog
Bogens tekst er maskinlæst, så der kan være en del fejl og mangler.
hirst Lesson tn Development.
33
convenience of a sliding shutter in the workroom will here be
apparent), and the protecting cover removed for one second;
in very dull weather two seconds may possibly be necessary.
After exposure, remove again to the workroom, and (still
by yellow light, of course,) remove the now invisibly im-
pressed plate, and prepare for development.
For reasons explained in our introductory chapter, we
strongly recommend the hydroquinone developer. This
may be bought, ready prepared, of most photographic dealers;
but as soon as the student feels confidence in himself we
advise him to make his own. The following is a reliable
formula:
Hydroquinone
Citric Acid.......
Potassium Bromide
Sodium Sulphite ...
Alcohol...........
Water to .........
... 720 or 160 grains
... 270 or 60 „
135 or 30 „
... 9 or 2 ounces
4 or 1 „
... 99 or 20 „
Dissolve the citric acid, bromide, and sulphite together,
in about sixty (or fourteen) ounces of water; dissolve the
hydroquinone in the alcohol, and then add gradually to the
other solution with frequent shaking; finally add the rest
of the water.
B.
Potassium Carbonate ... 13% or 3 ounces
Sodium Carbonate ..............134 or 3 „
Water to ......................90 or 20 „
, Before beginning to develop a plate, we must make up a
fixing bath in a clean porcelain try, the following is the best
strength for this bath:
Fixing bath for lantern plates.
Hypo ... ... ... ... 3 ounces.
Water... ... ... ... 20 »
This bath should not be used for lantern plates more than
one day ; if kept and used on a later occasion, stains will re-
sult.
To develop a lantern plate: Pour into a graduate* half an
ounce of A, half an ounce of B, and add one ounce of water.
Put the plate, film side upwards, into a small porcelain tray
(about 4 by 5 inches in size) and, witli a steady sweep,
flow the developer over its surface. Do not hurry; do not
splash the developer, or air bells will be formed; do not pour
the solution on the centre of the plate. The best way is to
*See Glossary.