Any questions in regard to photograph matters will be willingly answered by the Editor of this column, and we should be glad to hear from any of our club who can make helpful suggestions.
WHATMAN'S PAPER FOR PRINTING.
Whatman's drawing or water-color paper is a very pure paper, and may be sensitized and used for photographic prints. The process is quite simple. Dissolve 75 grains of chloride of ammonium in 1 quart of water, filter through cotton or filtering-paper, and soak the paper in this solution for three minutes, or until it is thoroughly saturated; then lay it on a clean flat surface to dry, using care in handling so as to avoid stretching or tearing. This process is called "salting the paper." The sensitizing solution is prepared as follows: Dissolve ¾ oz. of nitrate of silver in 8 oz. of water. Take two-thirds of this solution, and precipitate the silver by adding strong ammonia water drop by drop. This will cause the solution to turn brown. Continue adding the ammonia till this brown precipitate is dissolved and the solution becomes clear again. As soon as it clears, turn in the rest of the silver solution which contains no ammonia. The mixture will again become discolored, and must be cleared by adding a few drops of acetic acid. Filter and place in a glass-stoppered bottle.
Fasten a sheet of the salted paper to a flat board, and with a soft wide brush apply the solution, brushing first one way of the paper and then the other. Brush very lightly so as not to roughen the paper. The solution must be applied by gas or lamp light, and the paper dried in the dark. When dry it is ready for printing. The prints should be deeper than those made on aristo-paper. Tone in any good combined bath. The following formula may be used; and is also suitable for any mat-surface paper: Dissolve 1 oz. of hypo in 6 oz. of water, and filter. Dissolve 7½ grains of pure trichloride of gold in 1 oz. of water. Add this gold solution drop by drop to the hypo solution, shaking the mixture frequently during the operation. This is a stock solution. To prepare the toning bath take 1½ oz. of this stock solution and mix it with 7½ oz. of a ten-per-cent. solution of hypo. (A ten-per-cent. solution is made by dissolving 1 oz. of hypo in 9 oz. of water.)
Place the prints in this bath without previous washing, and tone to the desired color. Almost any tone from reddish-brown to black may be obtained, the tone depending on the length of the time the print is left in the toning bath. Wash well and pin on a flat board, and set the board in an upright position till the prints are dry. The paper is of sufficient weight not to require mounting, and the paper should be cut large enough to leave a wide margin all round the print. For a 4 by 5 picture cut the paper 8 by 10 inches. In printing, the paper—except where the picture is to appear—should be covered. Take a piece of opaque paper the size of the sensitized sheet, and cut an opening in the centre a little smaller than the negative from which the print is to be made, and print the picture through this opening.
Another way to shield the paper from the light is to cut a square of paper the size desired for the finished print. Paste this lightly in the centre of a sheet of plain glass, and paint all the clear glass with Strauss's marl or Gihon's opaque. When the paste is dry remove the paper, and print through the clear glass in the centre.
Pictures made on Whatman's paper are not common, as few amateurs know how to make them, but the process is very easy. The paper can be sensitized with any of the solutions used for making tinted prints, directions for which have recently been given. A collection of fine prints made on Whatman's paper, using papers of different tints, is always much admired, and well repays one for the extra labor required to prepare the paper.
Sir Knight Arthur F. Atkinson, 1711 I Street, Sacramento, Cal., who is president of the Niepce Chapter of the Round Table, a chapter devoted to the interests of amateur photographers, has sent out circulars to all the members asking their co-operation in reorganizing the chapter. This chapter has been very active, and has been a great help to its members. It should not be allowed to disband, and the charter members will gladly welcome any members of the Camera Club to its membership who will help to sustain the chapter. Send names and addresses to the president. The editor of this column is an associate member of the Niepce chapter, and hopes to see it as large and flourishing as formerly.
Sir Knight Howard Whipple, N.D., asks for a formula for making a toning-bath out of dentists' scrap-gold. Sir Howard will find his answer in No. 868 of the Round Table.
Sir Knight Richard P. M'Coun asks how to prepare paper for printing, and if the soda developer can be used over after the pyro has been added. Directions for preparing sensitive paper are given in this number. The developer should be thrown away after using, unless one is going to develop in a day or two. The developer works very slowly after having been once used, though it is useful in starting development when the exposure is over-timed.
Sir Knight Burt Tuck asks if there is any remedy for over-exposed negatives. See No. 821 of the Round Table for treatment of over-exposed plates.