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.
Irregular Or Patchy Development. 1. Overexposure and under-development will cause an uneven appearance in the print.
2. Uneven development is another cause. Immerse prints evenly in the developer.
3. Not rinsing properly in acid water between developing and fixing will cause irregular spots and streaks.
Mixing Solutions. In mixing all solutions chemicals should be added to the water in the order given. There is a reason for all of the chemical combinations. If the local water is not fairly pure, it is advisable to use distilled, or rain water, as this can be depended upon.
Saturated Solution. To mix a saturated solution of bromide of potash, add sufficient bromide crystals to a few ounces of water, so that when it is thoroughly dissolved some bromide crystals will remain at the bottom of the bottle. The undissolved crystals prove the solution to be saturated.
Acid Water. Acid water for rinsing prints between developing and fixing cannot be too strongly recommended.
Acetic Acid. Do not use acetic acid C. P., as it is too strong.
Other Developers. Metol-hydroquinone has proved to be an excellent developer and can be depended upon for results when mixed in the proportions given in the formula. Its keeping quality is also excellent. Ortol-hydroquinone developer is rapidly coming into favor, as it apparently equals metol-hydroquinone in every respect. Following is a formula which may be used:
1033.
Water.............................................. | 40 oz3. |
Ortol.......................................... | 30 grs. |
Sulphite of Soda (Dry)........................... | .. 1 Oz. |
Hydroquinone........................................ | 90 grs. |
Carbonate of Soda (Dry)................................. | .. 1 oz. |
Use bromide as necessary to insure clear whites.
1034. The following formula for amidol developer will also produce good results. Amidol does not keep well in solution and should be mixed and used as needed:
Water......................................... | .. 4 ozs. |
Sulphite of Soda (Dry)........................ | 40 grs. |
Amidol................................ | 10 grs. |
 
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