MAKING THE TRANSPARENCY.
It will be noted that as the effect of the light is to cause the film to refuse the powder, the parts acted upon by the light will remain lighter. This being the case, an impression taken from a negative would give a negative, so that if the finished result is to be a positive, as is usually the case, a transparent positive must be used for printing from. Many opportuni ties will, of course, be presented for making use of this fact, such as where I a. negative is required to be reproduced. Moreover, the negative will be reversed as regards right and left, and as the contrast 1 and gradation, as well as the rendering of large masses of shadow or light, are entirely under the control of the operator, I it provides an excellent means of produc ing negatives for use in the single-transfer process. This offers the further sugges tion that to secure the truest rendering of an object by the process, it will be neces sary to have a reversed transparency, and the process by which one may be produced is at once indicated—namely, the single transfer. In making this transparency, it
is essential to bear in mind that it should have the same class of gradation, tone, and contrast as would be looked for in a negative, a transparency of the ordinary kind being too thin and weak. Therefore, it should be printed and developed to look decidedly dark, as otherwise the detail in the lights will have little contrast, and consequently little chance of properly im pressing the plate. The subject chosen should be one showing a pleasing variety of tones, full of detail in the lights and with great transparency of shadow—plenty of clear contrast, in fact, throughout the picture, without. any approach to hardness. A weak subject lacking in contrasts, or of a monotonous tone, will present only a dirty picture.