This section is from the book "Complete Self-Instructing Library Of Practical Photography", by J. B. Schriever. Also available from Amazon: Complete Self-Instructing Library Of Practical Photography.
Developing. After securing a negative which you think is exposed approximately correct, it is advisable to start the development of the plate in normal developer, watching it closely (see Universal Developing, Volume II). As soon as the image appears, examine it by holding the plate before the ruby lamp, looking through the plate. Observe whether the plate is developing evenly and if it was properly timed. Should the plate show signs of under-exposure immediately treat it as an under-exposed plate. (See Developing Under-Timed Plates, Volume II.) If over-exposed, change at once to a developer prepared for overexposures. (See Developing Over-Exposures, Volume II.)
226. A good plan is to have three trays ready for use when developing; one containing developer prepared for over-exposures, another holding developer for under-exposures, and the third for the normal developer. By preparing these three developers before beginning work, you can immediately manipulate the development and overcome all difficulties that may arise from improper exposure.
Practice Work. In preparing this lesson it is advisable to make two exposures of this style of lighting. Give the first plate what you would consider a normal exposure, while for the second give a longer exposure. Do not attempt to hurry when lighting and posing the subject. Study every move necessary to the securing of a proper light on the subject. When this is accomplished observe the image on the ground-glass and make a careful estimate as to what you think will be the required length of exposure. Everything being in readiness, insert the plate-holder into the back of the camera, draw the slide; then, having the subject in the desired position, with the eyes at the proper angle, make the exposure. A memorandum should be made of each step of the procedure, that your future work may be based upon the results previously obtained.
228. If this instruction has been thoroughly studied and carried out there will be little need for experimenting, and you should produce satisfactory results from the beginning.
229. Develop the normally exposed plate first, according to the instruction. After the plate has been fixed and rinsed, take it to the white light and examine it. If there is error in exposure or development, on developing the second plate strive to overcome the difficulty. If the first plate was properly timed you will know that the second plate, which received a longer exposure, is over-timed. Provide against flatness by developing the plate for over-exposure. If, on the other hand, the first plate should show signs of slight under-exposure, the second plate would be exposed about right and the normal developer should be employed. When the plates are dry, proof prints should be made from both negatives, on the back of which should be noted all data pertaining to their production. File these proofs in your regular proof file.
230. Before attempting to make other lighting effects, continue with Plain Lighting until satisfied that you are able to secure the very best results. Compare the first proof prints with the studies in Plain Lighting given in this volume; also with the illustrations accompanying this instruction. Study each and every feature of the face, both in the original example given herewith and in your own print.
231. Proof prints, with important data noted on the back of each, should always be made from all experimental negatives, and then filed away in regular order for future reference and comparison.