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.
Exposure. Under each of the previous sub-headings we have given approximate exposures for the various subjects that you will be likely to deal with. Remember that these exposures are only approximate, and a little latitude on the side of over-exposure can be easily remedied in the developing. If the sky be particularly dark there is not so much risk of over-exposure. It is when illuminated by a full moon, or on summer nights when the sky is distinctly blue, that you run the risk of overexposure. For daylight work there is an established rule, "expose for the shadows and let the highlights take care of themselves." This does not apply to night work, for if suf-ficent exposure were given to fully time the shadows you would produce a daylight effect. It is not desirable to produce full detail in all portions of night pictures; do not attempt to secure any more detail than you can actually see.
Development. Development must be carried on in a very dilute and slow working developer. On no account should a plate be developed in strong developer. A regular pyro-soda developer, diluted with water, such as the Universal Developing Formula given in Volume II., will give excellent results, while if a quick developing agent, such as rodinal be used, dilution must be carried to the extreme - 1 dram in 20 ounces of water. Be sure to keep the plates covered during development, and thus protect them from the ruby lamp, which, owing to the prolonged development, is very likely to cause fog.
527. Make proof prints from each experiment, and place your notations, which will give you full information regarding the manner in which you proceeded to secure the results, on the back of each, and file in your proof file for future guidance.