Page 111 - The Wellington photographic handbook

made on S.C.P. With fixed focus or other enlargers using day-
light, the exposures are quite short. For example, with a good
stainless negative, and an enlarging apparatus in which the lens
is working at an aperture of f/32 ascertained as above described,
if a Watkins' meter be laid pointing up to the sky beside the enlarger,
the exposure with S.C.P. will be about as many minutes as the
meter paper takes seconds to darken to the standard tint.
When enlarging by incandescent gas from quarter-plate to
whole-plate, with an enlarging lantern and a condenser, using a
quarter-plate R.R. lens at full aperture—the effective aperture of
which would under the circumstances be about f/24—the exposure
on S.C.P. would be something like half an hour.
It will be seen that these exposures are by no means prohibitive
in length, and one gets all the comfort of using a gaslight paper
which can be developed in any ordinary room illuminated by
artificial light.
The photographer is cautioned, however, against making the
enlargement in a well-lighted room. The paper may be adjusted
and pinned up with the same light in the room as is used for the
development of S.C.P., but the room should then be darkened, as,
if the paper is exposed to the general illumination during the whole
time necessary for the exposure, it will certainly be fogged.
Otherwise no special precautions need be taken. If there is a
fire in the room, it will do no harm, provided it is screened so that
no direct light falls on the S.C.P.
For winter evening enlarging, S.C.P. will be found a very
convenient medium, while for richness and delicacy its results leave
nothing to be desired. Generally speaking Soft S.C.P. is preferable
to Vigorous S.C.P. for enlarging purposes.

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