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Kallitype

solution, prints, water, paper, minutes, ounces and developed

KALLITYPE PROCESS.—A printing process giving a dull matt-surfaced picture, similar to platinotype of bromide paper. The formula for the manufacture of the paper is not published The paper is, however, sold commercially.

The paper is much more sensitive than ordinary albuminized paper ; it will, therefore, be necessary to see that all operations with it, such as cutting up, placing in the printing frames, developing, etc , are all conducted either in yellow or in very weak daylight. It should be kept guarded from light and moisture.

may be said to be a combination of a printing-out and a developed process, as the image prints out visibly, but is not sufficiently brilliant until treated with a devel oping agent, which has the effect of bringing up the image bright and clear, provided the exposure has been correctly given. When placing in the printing frame it is necessary to see that the paper is quite dry, otherwise the correct exposure cannot so easily be determined, and the print will also lack brilliancy in color. When the air is very moist it will be advisable to dry it carefully. It must not, however, be made too warm, or it will produce fog. In a good actinic light, with a correctly exposed and developed negative, about five to ten minutes will be found necessary, in sunlight only about two or three minutes. The image can be examined, but is rather faint. As soon as the detail in the densest part of the negative appears it has been sufficiently exposed, and may be removed.

prints (which must be quite dry) are floated face downwards upon the following solution: Nitrate of silver 5o grains Sodium citrate x ounce Potassium dichromate I grain Tap or rain water to ounces Ammonia .88o I drachm This is made up by dissolving the silver nitrate in about an ounce of the water, and the sodium citrate and potassium dichromate in the remainder, and the two solutions thus formed are mixed together. The ammonia is then added, and the whole filtered.

Upon this solution the prints are floated for from ten to twenty seconds, after which they are placed face upwards upon a piece of clean glass for two or three minutes, in order to gain density. They are then immersed in washing solution No. composed of

Kallitype developer (as above) I ounce Sodium citrate 2 ounces Rain or tap water 20 ounces This solution can be used over and over again. In it the prints must remain for at least twenty minutes, a longer fime will not hurt them. The object of this solution is to remove the yellow color from them.

The developed prints are next washed in a solution made up with Sodium citrate i drachm Ammonia .88o 2 drachms Tap or rain water i quart for about ten minutes. The solution is then poured off, and the prints treated with a fresh supply. This solution, after the prints have Veen in it for about ten minutes, should not show any sign of yellowness. If so, a fresh supply should be taken, otherwise the prints will be yellow. The print should be kept moving in the different baths, and after the last they are removed, washed for a little time in water, and dried.

The correct exposure of the print can be seen in developing. When it has been insufficient the action of the developer will be very slow. If over-exposed the prints will appear mealy, and when much overdone they will develop very heavy and muddy.

The developing solution can be used over and over again, until it loses its power and the prints lack brilliancy. It can then be restored by adding to every lo ounces of it, 20 grains of silver nitrate dissolved in as little water as possible.

The following should be noted. Prints, when not developed the same day as printed, must be kept quite dry or they will suffer. The washing solution used at the end should always have a distinct smell of ammonia. In printing from weak negatives additional contrast may be secured by adding a little more of the potassium dichromate to the developer. A stock solution, made up of 8 grains to the ounce of water, should always be kept on hand, so that a little may be added when required. One drop of this added to 10 ounces of developer will give greater brilliancy and contrast.

KINETOGRAPH.—See Chronophotography. KINETOSCOPE.—See Chronophotography. KNIFE, CUTTING.—See Trimmer.