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Magnification Calculations

Sometimes the distance between test specimen and image detector is increased to obtain magnification in the image.   Magnification is especially useful when parts being inspected and their details are very small.  The farther the test specimen is from the image detector, the greater the magnification achieved.   The amount of magnification can be calculated using the following formula.

         M = (a + b) / a

         Where:  M = magnification
                        a = distance from source to object
                        b = distance from object to detector



Example Calculation
Calculated the geometric magnification when the source to object distance is 80cm and the object to detector distance is 30cm.

  M = (a + b) / a

  M = (80cm + 30cm)/80cm

  M = 1.375