The MicronEye requires a high contrast scene in order to image the object onto the OpticRAM. Unlike a TV camera which can respond to shades of gray, the OpticRAM is a digital device where each picture element will only respond to a black and white representation of a scene. All portions of the scene lighter than an arbitrary threshold are considered white and all portions of the scene darker than the threshold are considered black. If the exposure time is increased more of the scene falls on the white side of the threshold barrier. As the exposure time is decreased more of the scene falls on the black side of the threshold level.

The threshold level can be affected in one of three ways: (1) changing the exposure time; (2) changing the f-stop on the lens; and (3) changing the light on the scene itself. Doubling the exposure time is the same as opening the f-stop by one stop (changing the f-stop to the next smaller number) or, in other words, doubling the amount of light.

For optimum results from your MicronEye, careful consideration must be paid to lighting. In general, arbitrary lighting of the environment will not produce optimum results as it may result in low-contrast images, reflections, shadowing and extraneous details. A good lighting system illuminates the scene so that the complexity of the image is minimized while the information required for inspection or manipulation is enhanced.