The development of dry plates is caused by the contact of an active developing agent with such silver salts as have been acted upon by light.

If a developer so balanced as to be vigorous and strong is used it will attack the exposed silver rapidly and darken it quickly, forming a coarse grained deposit of silver. The image thus formed will not possess full delicacy and detail. If a developer so balanced as to be slow in its action is used it will search out and produce an image of fine grain with full delicacy and detail.

Judged by results the slow working developer has every advantage over the stronger developer, but in darkroom development there are two reasons why the slow working developer is not practical. First, the length of time required to develop has made the work of darkroom hand development tedious and slow. Secondly, the length of time required to carry the development to completion with an extremely slow working developer makes it necessary to use caution as to the strength of the darkroom light, or fog will result. This condition makes a quicker developer the best choice for hand development although the quality of the finished negative is not entirely satisfactory.

There is now a device in general use that makes it possible to realize all of the advantages of slow development without any of its disadvantages - a device that makes it possible to produce negatives of fine grain with an absence of red-light fog - a device that eliminates the tedium of hand development - eliminates the probability of scratches, finger marks and frills caused by handling, and this device is the Eastman Plate Tank.

With the proper use of the tank good results are assured and the work of plate development is made easier and at the same time better. Use the reliable, conveniently constructed Eastman Plate Tank.

February. Bulletin: The Eastman School Of Professional Photography For 1911

Boston, Mass...........Jan. 31, Feb. 1, 2

New York City.......... . Feb. 7, 8, 9

Philadelphia, Pa...........Feb. 14, 15, 16

Syracuse, N. Y...........Feb. 21, 22, 23

Toledo, O............ Feb. 28, March 1, 2

Cincinnati, O.............March 7, 8, 9

Chicago, Ill........... . March 14, 15, l6

Omaha, Neb............March 21, 22, 23

St. Joseph, Mo...........March 28, 29, 30

February The Only Condition StudioLightMagazine1911 38

The difference between the ordinary photograph and the kind we make is due to our skill and high grade equipment.

Every sitter is given individual attention and treatment and the results we produce are photographic portraits - not merely photographs.

Let us demonstrate our skill by making for you the best portrait you have ever had.

Aristo Motto

"WE believe permanency is the Keystone of Photographic Success, and all brands of paper bearing our Trade-mark are manufactured on this principle. We hold our consumer's reputation and success identical with our own. We surround both with every safeguard known to chemical science and our own experience."

Wm. Loeb, Jr., Collector of the Port of New York.

Wm. Loeb, Jr., Collector of the Port of New York.

Pirie Macdonald Photographer-Of-Men New York.

From an Artura Iris print.