Middle left stick

Calculator stick

Test strip

A test strip is usually made using a strip of the photographic paper to be used for a full-size print. The paper should be fixed firmly in place so that id cannot move during the exposure process. A range of exposures is then used on various parts of the strip to determine the optimum figure before committing to the full print.

A timer is set to a period determined by experience of using a particular enlarger, and the relevant magnification (the distance from the lamp to the paper remembering the inverse square law). An aperture of f/11 or f/8 and an interval of five seconds might be typical when enlarging a medium-format negative to A4 size. In the example above, the timer was set to 15 seconds and the test strip was exposed for the first time. Three-quarters of the test strip was then covered with card before making a second 15-second exposure. This process was repeated this until the last quarter of the test strip was covered. The result was four zones exposed for 15, 30, 45 and 60 seconds.

Please Support OPS

Donate using PayPal
Amount:
Go to top