If commercial muriatic acid be used, the prints will be discolored and turn yellow.
For each batch of prints fresh acid baths must be used.
After the prints have passed through the acid baths they should be well washed in three changes of water during about a half hour. It is advisable to add a pinch of washing soda to the second washing water to neutralize any acid remaining in the print. Do not use water that contains iron, as it tends to turn paper yellow. Soft water is the best for this purpose.
W. & C. Sepia Paper.
The “sepia” paper is more easily affected by faint light, and, therefore, increased care must be taken when printing.
To develop, add to each ounce of the developing solution 1 1/2 drachms of sepia solution supplied for this purpose, and proceed as described for black paper.
The solution must be heated to a temperature of 150° to 160° F., to obtain the greatest amount of brilliance and the warmest color, but very good results can be obtained by using a cooler developer.
Variations Of The Sepia Developer.
The Glycerine Process.
By this method of developing platinotype paper, many negatives which have been discarded on account of the dim, flat, non-contrasty results which they yield, in the hands of one possessing a little artistic skill, produce snappy, animated pictures. On the other hand, from the sharp and hard negative, soft, sketchy effects may be secured.