NOTES ON DEVELOPMENT.
a general rule, do not try to develop very many plates at one time; it is better to develop two or three plates in an evening, and do them -well, than to try a dozen or more and be hurried and make failures of many. We speak from experience. On one occasion we brought in from a trip to the country about two dozen plates; some instantaneous, some timed exposures, and some detectives, developing them all in one evening. The result was natural, a few fairly good negatives, and some pass. able, the greater part poor. This was several years ago.
The only exception to the rule is where one is copying pictures of the same general character, and using one kind of plate, and knowing by experience the precise time for the exposure.
When you get ready to develop a plate be sure you know what the plate is, from what holder, and what exposure was given. Then you will be prepared to treat it intelligently.
Some photographers recommend soaking a plate in a bath of cold water before placing it in the developing tray. We cannot recommend this mode of procedure, for the reason that there are apt to be particles of vegetable matter in the water which are liable to cause spots in the plate. One spring we had a great many plates covered with spots, which we traced to the prelimi nary water bath. Since giving up this practice we very rarely find a spot on a plate.
Immediately after putting the plate in the developer take the tray in the two hands and rock it gently, so that the solution can quickly cover the entire plate. Bubbles will not touch and adhere to the film if there is enough solution in the tray to rise above the plate at least a quarter of an inch.
It is preferable always to have the tray away from the dark lantern, holding it under the light only for a second or two at a time, to see how the development is proceeding; especially is this the case with all very rapid plates, which are so much more sensitive to the light than slow ones. With gas giving the light in a dark-lantern this can be very easily managed, turning the light up or down as desired.
In developing, (and this applies more especially to pyro solu tions,) if the plate has been over-exposed, the image will come up rap- idly; if under-exposed, it will appear very slowly. If it
shows over-exposure a few drops of bromide should be put in the developer at once, and the tray rocked to spread this through the solution. Therefore have your bottle of bromide where you can get it quickly in the dark.
To judge when a plate is fully developed is learned only by experience. It would be well for the beginner to make two or three exposures of the same view with the same number of sec onds, and develop them one after another, giving one more time than the other, and note the results of under and over development.
Do not use the fingers to take plates out of the developer or fixer. If you cannot get the instrument previously described use a knife with large blade at one end for the developer, and small blade at the other end for the fixer, and keep both blades clean.
Or an ivory paper cutter, with ends of different shapes, so that you will always know -which end is for the fixer.
In warm weather it is well to place the plate before fixing in an alum bath for a few minutes; this will harden the film and prevent what is called frilling or the peeling of the film at the edges. Some recommend alum in the fixing bath. We have never had a case of frilling, but old photographers advise the alum, and it is safe to do as they say. In developing plates in the summer we advise placing the tray in a larger japanned or wooden tray filled with broken ice.
Whenever it is possible use distilled water for dissolving chemicals. This is not necessary, however, for hypo. In winter collect clean snow, melt and filter it, and use in the place of distilled water.
As a general rule the simplest developers are the best. It is safe to follow the directions given by each manufacturer in using his plates. It is for his interest to have his goods produce the finest results, and he would advise nothing that he did not con sider good. Still, we think hydrochinon the most generally satisfactory of all developers for every kind of plates.