DEFECTIVE NEGATIVES.
Defective nega;ives may be caused by under or over exposure or by careless handling during development and subsequent operations.
Over or under-development is usually occasioned by the faEt that the inexperienced operator is unable to tell, under the dark-room light, IN hether he has carried the develop ment far enough or not and he is extremely likely to err on the side of under-develop ment.
A properly exposed n e cra. tive should be de veloped for five minutes. If you feel that you have under-exposed the negative no harm will come from developing up to eight minutes. The beginner will, as a rule, secure better results by timing develop ment by the watch than he will by trying to judge the appearance of the negative, shows an under exposed negative clear in the dark parts or shadows with an entire absence of detail, the high lights or white parts of the subject being black, also lacking in detail. This fault is caused by making snap shots indoors, or in the shade, or when the light is weak, late in the day, or by closing the lens too soon on time exposures.
Fig. 2 shows an over-exposed and over-developed negative, full of detail but flat, lacking all contrast and brilliancy and at the same time it looks black or dense.
Caused by too much light.
Negative develops evenly, shadows almost as fast as high lights.
No contrast, and no deep shadows.
If a negative is known to be over-exposed before development is begun, it can be largely overcome by the addition of bromide of potassium to the developer, before development begins, and a bottle containing Bromide of Potash, i oz. Water, - - Io ozs.
should always be at hand when you are developing.
Use i to 4 drops for each ounce of developer according to amount of over-exposure.
After the Bromide has been added to the developer, it should not be used for another negative unless it is known to have been over-exposed.