Naked Eye - Small Objects and Maps

Small Objects and Maps

Observing a nearby small object without a magnifying glass or a microscope, the optimal distance is 20–25 cm. At this close range, 0.05 mm can be seen clearly. The accuracy of a measurement ranges from 0.1 to 0.3 mm and depends on the experience of the observer. The latter figure is the usual positional accuracy of faint details in maps and technical plans.

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