The Dictionary Of Photography

A True Historic Record Of The Art & Practice Of Photography 100 Years Ago.

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Cloud Negatives
of this clearing bath immediately after fixing, the plate being only just rinsed after being taken out of the fixing bath. The following solution has been specially recommended for removing pyro stains and is very effectual: -
Thiocarbamide ...... ... ... 30 grs.
Citric acid ......... ...... 10 ,,
Water           ... ... ...... ... 5 ozs.
Cliche. A term applied to the negatives, positives, and moulds.used in reproduction.
Clips. The wooden spring clips sold at the oil shops can be made much less liable to injure prepared papers and prints, by dipping the gripping ends in melted paraffin wax. The gripping ends of metal clips may be dipped in the sensitive bitumen varnish mentioned in another place (see Asphalt Processes). The coating becomes gradually hardened and increasingly pro-tective by exposure to light.
Cloud Negatives. There are few landscapes or seascapes taken by amateurs which would not be improved by the addition of clouds - in fact, in many instances an otherwise poor print may be made a picture by the judicious use of the same. It must, however, be borne in mind that clouds which are unsuit-able to the landscape, or which are differently lighted, are worse than a blank sky. For taking cloud negatives it will be found that slow or medium plates, rich in silver and preferably coated with a bromo-iodide emulsion, will answer well; but the finest effects will be obtained by the use of isochromatic or orthochro-matic plates, with a yellow screen interposed between the lens and plate. The majority of landscape photographs have the horizons from one-third to two-thirds up the plate; therefore it would not be advisable to point the lens to the zenith to obtain cloud negatives, as the lighting, as a rule, is different to that ob-tained nearer the horizon. It will be found that good cloud scenes may be obtained without much difficulty from any open space near London or any other city or town ; and the author has obtained very fine negatives from the upper windows of an ordinary dwelling house, and in practice he makes it a rule, if possible, to include some of the housetops or distant landscape in the field of view, though this is totally disregarded in exposure