SUBJECTS OF OVER-NORMAL ACTINIC CONTRAST The extreme subject of this class is usually a combination of interior and exterior as il lustrated by the example of the cloud and the window casing on page 93. Such subjects should be avoided when possible. If the con trast is not too abnormally great however, much may be done to render such subjects in good gradation in spite of the necessary over exposure of the brighter parts, by exposing just enough to overcome the inertia of the emulsion one or two times where the darker intensities impinge and then developing but one half the normal time in order not to build up excessive opacity and contrast in the negative. The usual error is to over-develop such exposures thinking to bring out more detail in the shadows and in doing so the opacity contrast is so increased that the shadow details are usually eliminated or "burned up" in the effort to obtain the texture or detail of the high lights in printing a picture from the negative. If however the exposure be
made by measurement so that the lowest plane in which detail is desired is made to overcome the inertia as stated, this latent image or effect, lying as it does on the outer surface of the emulsion, will develop very soon after the developing solu tion is applied and without any modification of the usual method except to avoid too great opacity in the most exposed parts by reducing the normal time of development as has already been stated. Or the negative may be normally developed and the too opaque parts reduced locally after the negative is fixed, as will be explained in another chapter (p. 120). It is evident that for such a subject an emulsion of the greatest possible latitude should be used. The use of film, and non-halation and double coated plates aid in securing such subjects. Plate XI illustrates such a subject photographed on film with the sky and field reduced locally.