HF The History of Photography 600pág

430 The gelatine period
Pl 232
The portrait photographer ADOLF OST of Vienna improved upon Nadar's system
in 1864 by using two arc lamps, the main illumination being generated by 80 Bunsen
elements, while another smaller lamp powered by 40 elements was placed farther
from the sitter and lower down to light up the shadows. Blue glass screens were interposed
between the lights and the sitter. Ost arrived at exposures of 7 seconds (using
wet collodion), but the running costs of the installation were exceeding! y high, so its
use was restricted to dark days. Portraits taken by electric light, up to the size of
13 in. x 16 in., were shown by Ost at the first photographic exhibition in Vienna held
in May and June 1864.
Big photomechanical printing firms, and some ordinary photographic printing
establishments, turned to electric light when insufficient daylight might otherwise
have brought work to a standstill. The Woodbury Permanent Photographic Printing
Co., for instance, installed about r 870 a powerful dynamo to provide the necessary
illumination for making gelatine reliefs. The 1 ,200 candle-power light was a
poor substitute for sunlight or daylight, its actinic power being only 2
\ that of sunlight
on a summer day. Compared with IO minutes' exposure by sunlight, electric
light required 4 hours to give the same result. Yet it was a great advance on the
limelight formerly used at this establishment, which necessitated an exposure of as
much as double that time.18 Only big concerns, of course, could afford a dynamo,
and, moreover, for portrait photography this light-source, like other artificial light,
became practicable only in conjunction with fast gelatine plates.
In view of the English climate it is not surprising that the first studio in the world
using electric light exclusively was opened in England. In September 1877 HENRY
VAN DER WEYDE installed a powerful gas-driven Siemens dynamo in the basement
of his house in Regent Street, London. The most prominent object in the studio was
a huge parabolic reflector over 4 ft in diameter, painted white inside, and suspended
from the ceiling by a system of pulleys enabling it to be moved about so that light
could be directed on to the sitter from any point and at any desired angle. To shade
the sitter's eyes from the dazzling 6,ooo candle-power light, a 4 in. concave mirror
(similar to Gaudin's and Delamarre's) was fixed in the centre of the reflector, the
positive carbon projecting through it. In the opening of the reflector was fitted a big
Fresnel lighthouse lens composed of concentric rings of prisms, which converged the
light rays to a point about 6 ft away. Behind the sitter were screens to reflect the light,
as shown in the illustration.
This arrangement allowed Van der W eyde to take a large number of portraits in a
short time. Exposures were stated to be 8 to IO seconds for 'Promenade' portraits and
2 to 3 seconds for cartes. After the Prince of Wales had set the fashion for having one's
portrait taken in the evening (he was photographed at midnight after the opera)
fashionable ladies came for sittings in evening dress, on the way to or from the
theatre, balls, or presentation at court. Indeed, it was not rare for society beauties who
had sat for their portrait on the way to the opera to have proofs handed to them in
their box at Covent Garden, electric light being used for printing as well as for taking
the negatives.
By 1882 Van der Weyde was well on the way to making the fortune which, about
six years earlier, a leading London photographer had forecast was assured to the man
who invented a method of taking good portraits without daylight. It was a November
day when Van der Weyde, a successful American painter whose pictures were
hung on the line at the Royal Academy, had come to be photographed, only to find
that the light was too bad for a successful sitting. In parting, the photographer commented
upon the inventive genius of Americans and challenged him to find a way