Dense negatives with strong lights and black shadows, with little gradation between the two extremes, should be printed in a very strong light, preferably sunlight. It is also advisable at times to slightly expose the paper to light to soften the glaring high-lights.
Broken negatives should be carefully put together, and a piece of unsalted paper glued firmly to the glass side. When dry the paper will contract slightly and draw the parts closely together. In printing, the frame is laid on a board, kept revolving by means of a meat-Jack or other contrivance, so that the light does not come from one side only. The paper can be made translucent by any of the known methods.
Filling the are two methods of laying in the negative; it can either be placed directly in the frame, or made to rest on a thick piece of plate glass previously inserted. This glass must be kept thoroughly clean on both sides. The negative must also be dusted on the film side and well cleaned at the back, all pieces of emulsion and other foreign matter being carefully removed.
The description and illustration of the printing frame is given under that heading.
Every care must be taken to guard against breakage of the negative. This can easily be • effected by many ways—by dropping carelessly in the frame, warpage of the wooden frame, unequal padding or backing, improper placement of the backboard, pieces of grit or other sub stances between the negative and the glass plate.
After placing the negative in the frame the sensitized paper is laid on it in the required place. This can be ascertained by holding the negative and paper up to the light while adjusting the latter in position.
Behind the paper pads of blotting-paper or felt cloth are placed to ensure even contact of the paper with the negative. This should not be too thick or uneven. The backboard is then inserted, and should fit properly, and the pressure given by means of the springs or wedges should be perfectly even all over; not too strong, or the glass may break, but sufficient to hold the paper firmly in place and prevent it slipping when examining.
The cutting of the paper, filling the frames, and examination of prints should all be carried on in a weak or yellow light.
Save in exceptional cases, as, for instance, with dense negatives, the exposure should be made in a bright light, but not sunlight. Care must be taken to protect the frame from shadows, stray lights, or reflections.
After a little time, the frame should be carried into the weak or yellow light, and the print examined by turning back half the backboard and carefully lifting up the sensitized paper. This operation is repeated at intervals until the print is finished. In examining prints never expose them to direct light, or the purity of the lights will be ruined.
The color of the print should be darker than required for the finished picture to allow for the loss which takes place in the subsequent operations. Experience alone will guide the opera tor in judging the right time to remove the print from the printing frame, as, to a certain extent. it depends upon the kind of toning bath used, some reducing the color of the image more than others.
Vignetting, Combination Printing, &c., will be found under those headings.