Watch temperatures!

You have heard this warning often, but it bears repeating. It is for the man in the dark room or printing room, but it is also for you, as you have these men in your charge.

In the greater portion of this big country at this time of year, the water from the tap is too cold to use either in the developer for plates or paper. It is a very simple matter to temper it down, but it isn't always done. The result is poor negatives or poor prints.

A plate developer that is too cold produces thin, flat negatives - if too warm it produces too much contrast. The right temperature is 65° F.

A great many photographers use Eastman Plate Tanks, and once the right temperature is secured, these will keep it right for the length of development. Don't expect to make up a developer at a temperature of 55̊ F, and have it warm up in the tank, just because your workroom is warm. If the developer you place in the tank is too warm or too cold, the tank will keep it too warm or too cold, regardless (within limits) of the temperature of your work room.

It is always advisable to boil water that is used for developer, and if this is done the water can be placed in a large bottle and kept where it will not become too cold for use.

From An Artura Iris Print By A. F. Bradley New York.

From An Artura Iris Print By A. F. Bradley New York.

Boiling drives the air out of the water and so eliminates much of the danger of air bells on your plates. This is a common complaint where water is under great pressure and is likely to become aerated.

But it must be remembered that water also absorbs air very rapidly, so that water boiled for developing purposes should be used within a reasonable length of time or kept in bottles well filled.

Many photographers are now using open tanks for developing, and it is not so easy to temper several gallons of solution once it has become too cold for use if the tank does not have an outer jacket that can be filled with warm water.

Bottles of warm water can be placed in such a tank, but are likely to break if they are too hot. A glazed fire brick may be heated and used to advantage, or any of the various electric appliances used to heat water may be used for this purpose if they are of the type made to place in the water.

Whatever the method may be, correct temperature is of sufficient importance to have it used regularly, for nothing will upset an even run of quality so quickly as radical variations in the temperature of developers.