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.
Thin Negatives. Thin negatives with transparent shadows are due to under-exposure and can seldom be improved by intensifying. (See Chapter IV (Developing Under-Exposures), Developing Under - Exposures). Thin negatives with foggy detail in shadows are usually the result of over-exposure. The negatives will be thin in the highlights and will make very unsatisfactory prints. Diluting developer with too much water will produce thin negatives. Under-developing will do the same. The results produced by these different causes are not the same, but the difference is very slight, so slight that it is not easily described. Negatives of this kind can be improved by intensifying. (See Chapter V (Purple Tones On Collodion And Gelatin Glossy Papers), Intensifying.)
Dense Negatives. Such negatives are generally obtained by over-developing, allowing the plate to remain in the developer too long. Remedy: Soak in hypo for twenty minutes and then reduce. (See Chapter X (Varying Water Conditions. Their Effects Upon The Manipulation Of Sensitized Papers), on Negative Reducing.)
Parallel Lines On Negatives. These are generally caused by too strong a fixing bath and bath not thoroughly stirred before using. These lines, however, generally occur when plates are fixed in a grooved box.
Part Of Plate Stained Yellow. Caused by plate not being entirely covered by the hypo.
Spots And Streaks Almost Transparent On Plates After Drying. Caused by water spattering on the plate when dry, or nearly dry.
Negative Drying Too Slowly. Caused by drying plates in too warm, too cold, very damp, or poorly ventilated room.
Negatives Evenly Developed But Drying Unevenly. If the negatives when partly dry are removed to another room which is much colder, or warmer, or if parts not dry are forced dry by fanning, they will dry unevenly. The part last dried will be more dense than the first part.
Negatives Full Of Dirt And Scum When Dry. Caused by dirt in wash water. Remedy : Before placing the negatives in the rack to dry, wipe carefully with a tuft of absorbent cotton thoroughly saturated with water. Clean your washing box every day.
Yellow Negatives, Even With Sodas Of Proper Strength.
Sometimes sulphite of soda when in solution, even though it tests the proper strength, loses its life by age and becomes worthless; that is, it does not have its color preserving quality. An indication of this would be if the plates were yellow and grainy; in such cases make up fresh sulphite. It is best to not use sulphite solution over a week or two weeks old; better make up a smaller quantity and renew more often.