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.
Bronzing In The Shadows. Where one is experiencing difficulty with bronzing shadows, which is principally the case with contrasty negatives where the shadows are almost clear glass - and frequently during damp weather - the addition of an ounce of glycerine added to 80 ounces of developing bath will usually overcome the bronzing. As a bath containing glycerine decomposes rapidly, it should be used only where bronzing exists and ought not to be mixed with the regular bath. This bath will not produce good results after two or three weeks use. Discard it after employing that length of time and make up fresh bath.
580. Another method for removing bronze from prints is to apply glycerine to the bronzed portions on the dry print before immersing in the developer. Then place the print in the developer, watch it carefully, and if the shadows or bronzed portions are holding back, by gently rubbing over the bronze surface with the fingers while in the developer, these portions will develop more deeply. The former method, of adding glycerine to the bath, however, is more commendable.
Using Developing Bath Continually. A developing bath can be used continually, but must be kept in proper condition. It must be of uniform strength at all times, and the same bulk of developer should be used. It is advisable to have a bottle containing fresh stock solution, from which the baths that are in use can be replenished. After using a bath once or twice, instead of adding 10 ounces of fresh solution, add 5 ounces of the fresh solution and 5 ounces of water. The object of adding water to this solution is that your bath is becoming charged with other chemicals liberated from the paper. The bath also evaporates and becomes more concentrated. Therefore, should you continually add fresh developer to this old or used bath, you would have a stronger bath than you started with.
582. Then again, a diluted bath does no harm, in fact one has better control over the developing of the print in a weaker bath, as there is more latitude for longer developing. Therefore, when replenishing the old bath always
IV - II use half water and half fresh developer. If the bath is used daily it should be filtered at least every two weeks. A bath like this can be used for many weeks, unless an immense amount of developing is done. About every six weeks, where baths are used daily, a fresh bath should be made up, consisting of one-third filtered old bath to two-thirds fresh bath, adding thereto the same quantity of water as old bath used. If the fresh bath develops too slow, add more thereto until the required speed is obtained. But remember, slow development is a good fault.
Poisoning With Platinum Developer. Platinum solution is poisonous to some people, causing the hands to crack and become sore. A salve composed of the following ingredients applied to the hands will prevent poisoning:
2 1/2 drs.
.. 1/2 oz.
Mix well, and add about 5 cents worth of vaseline. Apply freely to the parts affected.
Varnishing Platinum Prints. - Platinum prints which appear a little heavy and muddy in the shadows can be very much improved and made more transparent by immersing the prints (after they are thoroughly dried) in a bath of varnish. The Adamantine varnish, made by the American Aristotype Company, has proven very successful for this purpose. The ordinary white shellac varnish, obtainable at any paint store, also produces the desired results. When using the white shellac varnish, which is quite thick, reduce with equal quantity of alcohol, and in order that the varnish may dry rapidly add one drop of shellac drier to each ounce of solution. This solution should be well shaken before using.
Varnishing the Print. - Decant sufficient varnish into a tray slightly larger than the print to be varnished. Catch the corner of the print with a wooden photo clip and immerse by dipping the entire print under the solution, face side down, the same as you would when developing the print, drawing it through the solution. Then hold the print over the tray, allowing the surplus varnish to drain back into the dish; then hang up to dry. The varnishing of the print has a tendency to warming the tone, and for sepia prints either platinum or developing papers gives a very rich result. The prints should be varnished before trimming. To thoroughly dry the varnished print will require about fifteen minutes' time.