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How to Find the Length & Width on a Scale Photo

Imagine displaying a life-size picture of the Eiffel Tower. It would not only take up a tremendous amount of room but would require scaffolding and lifts to examine. Few people could take in the whole structure at a single glance, as they could if the picture were smaller. However, a standard photograph would be difficult to use if the viewer wanted to make accurate measurements of its length and width. The answer to such a problem is a scale photo, which shrinks its subject down to a proportional yet manageable size.

Ruler

Instructions

- 1
  Measure the length and width of the object in the photograph. Record these numbers.
- 2
  Examine the scale. This number often appears near the top or bottom of the photograph as a ratio. For example, 1:100 means that one unit of measurement in the photo equals 100 units in real life.
- 3
  Reverse the ratio to describe how the live object compares to the scale photo. For instance, 1:100 turns into 100:1.
- 4
  Convert the ratio into a fraction with the first number in the numerator and the second in the denominator, such as 100/1.
- 5
  Multiply your measurements by the fraction. For example, if the object in the photo measures 1 inch long and 0.5 inches wide, the real object is 100 inches long and 50 inches wide.

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