How to Calculate Magnification of a Compound Microscope
- 1). Obtain the magnification of the ocular lens. This is the lens closest to your eye and for most compound microscopes is ten (i.e. 10X). Occasionally this number is written on the nosepiece or near the ocular lens itself. Alternatively, consult the manual that accompanies the microscope.
- 2). Find the magnification written on the objective lens. The objective lens is located on the nosepiece, which often swivels to click into place one of several lenses. The lens pointed straight above the specimen you are observing is the objective lens in use. The number should be stamped clearly on the side of the lens and is generally followed by an X (e.g. 45X).
- 3). Multiply the magnification of the ocular lens by the magnification of the objective lens to calculate the total magnification. For example, on a standard compound microscope the ocular lens magnification is 10x. If viewing an object with the 10x objective lens the total magnification would be 100x, meaning the object appears 100 times larger than its actual size.
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