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.
Color Of Plate Too Gray. The color of the plate is, of course, governed entirely with your sulphite. On account of the small quantity of carbonate being used it may at times be necessary to reduce the strength of the sulphite; otherwise the plates are apt to be too gray. It is advisable to have a tinge of yellow in the negative. The weaker the sulphite the more color you will have, and vice versa.
Plates Frilling. As this is slow development care should be taken that the developer is not too warm, and that the hands are not placed in the developing solution too often, as every time you place your hands in the developer you are increasing the temperature, as the hands are naturally warm. Always use fresh strong hypo bath, and have it cold. If you find that the plates still show frilling treat them to a weak solution of alum immediately after fixing, always being careful to rinse the plates in water before placing in the alum. They must then be thoroughly washed before you set them up to dry.
How To Treat A Plate Which Has Not Been Sufficiently Exposed, So As Not To Lose The Negative Entirely. When you find that the exposure is too short for this development simply rinse your plate in water and transfer to a normal developer. Oftentimes you will find it necessary to treat the plate as ordinary under-exposed by soaking in water, and then finishing in a diluted developer.
How To Treat A Plate Which Has Been Sufficiently Exposed, But Too Much Carbonate Had Been Added To The Developer. Immediately remove your plate from the developer, rinse it for a few moments, and then place in a restraining bath, or add about ten drops of ten per cent, solution of bromide to your special developer; in other words, treat as over-exposed - developing to an excess and reducing afterwards.
Plates Developing In Streaks, Uneven Development. This is generally caused by allowing the plate to stand too long without agitating the developer. While it is not advisable to rock the tray too much, you should rock it occasionally.
Transparent And Semi - Transparent Spots In The Negative. These are generally caused by air-bells gathering on the plate when the plate is first placed in the developer. A very good plan is to swab the surface of the negative with a piece of absorbent cotton which is thoroughly saturated with developer. This will remove all air-bells, and will also remove any particles of dirt that might be in the developer, and in the tray.
Judging The Proper Amount Of Carbonate To Use When First Starting To Develop. Bear in mind that you can hardly use too little. It is better to start with too little carbonate than too much. You can always add the carbonate solution, but you cannot very well change it if you have added too great a quantity. Ten to twelve drops is usually sufficient to start with. If the image does not appear inside of two minutes add three to five drops more, and do not add any more for at least another minute, for when the developer once has sufficient carbonate it will develop quite rapidly.
Plate Appearing To Develop Properly But The Highest Lights Not Gaining Sufficient Strength. This would signify that you used too much carbonate. Add a very small quantity of the pyro stock solution, also a few drops of bromide; at times a few drops is all that is necessary to produce the desired results.