CLOUD NEGATIVES Clouds that are to be added to landscapes must be taken under similar conditions to those of the landscapes for which they are required. A large common or open space should be selected for photographing, so that a low horizon line may be included on the plate. And this low horizon line should be as unbroken as possible. The formation of clouds near the horizon is different from that at higher altitudes, and it is therefore necessary that clouds near the horizon should be included on the plate so that they may appear correct if the formation of the landscape picture necessitates showing sky near the horizon. Clouds taken right opposite the sun, or directly towards it, are quite useless for adding to the large majority of landscape pictures, as most landscapes are taken with an oblique front lighting. Clouds should therefore be photographed with a similar lighting. If the sun should be in the south at the time of photographing clouds, those about the north-west and north-east will be the most useful. As opportunities offer, cloud negatives should be taken with different lighting, and of varied character ; brilliant piled-up masses, rain clouds, broken-up skies, quiet, calm, summer effects, etc., so that a suitable negative can be
be selected when it becomes necessary to add clouds to a cloudless landscape. It is necessary to study the arrangement or grouping of the clouds on the plate so as to get the principal point of light, or the principal feature in the grouping, towards one side of the plate. The grouping must be such that it can be utilised in assisting the formation or composition of a pic ture whenever practicable. The principal cloud masses should form an angular line across the plate. The exposure for cloud negatives must be very short, ranging from one-sixtieth of a second for very light clouds, up to one-fortieth for heavy masses, using a rapid plate (zoo and D.), and lens aperturef/16 at mid-day in late spring or early summer. Development may be normal. With such short exposures the nega tive will be thin, and suitable in every way for printing into landscapes.