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for this task. The rest is up to the Mark I human

eyeball.

Place the K18 up to your face so that one eye

is looking through the central viewport. This

operation works best in a dark room so that there

are no other sources of reflected light. Slowly

scan the area for a brighter-than-average spot of

light (Figure

J

). It’s likely to be very small given

the size of modern digital camera sensors.

Cheaply available hidden cameras are small

enough to be concealed in air vents, clocks,

stuffed animals, fake electrical outlets, garden

decorations, smoke detectors, scent dispensers,

plants, picture frames, or almost anything else

in an office, ...