by Don Skinner

The Reproduction (Repro) Section, working in an ES-38 photographic darkroom, was responsible for processing exposed photographic film obtained from Reconnaissance aircraft missions. This film, after processing turns into photographic negatives and the negatives are exposed to expose photographic paper in one of three "printers". The photographic paper came in rolls of 250 feet and after a roll of paper was exposed to the negatives it went through an automated process to develop the latent images into photographic pictures. After the photographic paper was processed the roll or rolls for the mission were transported to the Imagery Interpretation Section.

DARKROOM, PHOTOGRAPHIC, PORTABLE, ES-38

The ES-38 is a transportable semi-automated photographic darkroom specifically designed to process aerial reconnaissance film and print the pictures on rolls of paper.. The ES-38 is designed to be transported in the bed of a 2 1/2 ton truck. The unit can also be operated while mounted on the truck. An external source of electricity and water is needed. Electrical power required for operation under field conditions is supplied by trailer mounted generator. Electrical requirement to operate the ES-38 is 115 volts AC, 60Hz approximately 3500 watts. A water source can be provided by a water tank trailer pulled by a jeep or another truck.

Negatives produced from aerial reconnaissance film are 4 1/2"x4 1/2", 9"x9" or 9"x18" depending on the type of camera used. The film is in the form of a long roll so after processing, the negatives will also be on this long roll.

Located inside on the left side of the ES-38 there is a contact printer, an enlarger and a continuous contact printer. The contact printers expose the photographic paper with the negative pressed flat onto the paper. This produces a picture the same size as the negative. These were used for the 9"x9" and 9"x18" negatives. The 4 1/2"x4 1/2" negatives went in the enlarger and produced pictures 9"x9". 35mm camera negatives could also be run through the enlarger with a special carrier.

Located inside on the right side are two identical automated processing machines. Developing, fixing, washing, and drying of exposed film and paper are accomplished by each of the two processing machines. Each processing machine consists of four tanks, 5 gallon developing, 5 gallon stop bath, 5 gallon fixing and 8 gallon wash water, a drying compartment, pumps for agitation and circulation, solution temperature control devices, and a variable speed film and paper transport mechanism.

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