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.
Print Refuses To Develop. If the print was properly exposed and the sensitive side of the paper was next to the plate, and the print still refuses to develop, you may have made a mistake in preparing your chemicals, or you may have become confused regarding the trays and are trying to develop with the hypo bath. Be very careful to label each bath and tray.
Gray Whites. If there is not enough bromide in the developer, the whites will turn gray. Add a few more drops of your 10 per cent. solution of bromide. If the print is under-printed and forced in development, it will cause a graying of the whites. It is also possible that the paper has been fogged by white or actinic light before printing or during development.
473. Stains All Over the Print may come from any of the following causes: By forcing development of an under-exposed print; by using too weak a developer; by not fixing sufficiently; or by not washing carefully after fixing.
474. Yellow Whites are caused by under-printing and then trying to force the print by prolonged development.
Prints Too Light. If your prints are too light it is probably because you have under-printed. Give a little longer exposure.
Prints Too Black. Possibly over printed. Expose less.
Flat Prints. Negative is probably very thin, weak in the high-lights and weak in the shadows. Dilute your developer about one-half, and be careful not to over-print. Remember, that diluting developer on gaslight papers gives contrast; strong developer gives softness.
Print Too Dark After Fixing. This would indicate that the print was fully exposed, and should not be carried quite so far in the developer. Full timed exposures can be improved by removing the print from the developer just before it is dark enough. It will develop a trifle in the water, and unless thoroughly rinsed will continue to darken until it reaches the hypo bath.