This factor is used to calculate the true position of the focal plane as the microscope is moved up and down.
The focal plane moves a distance that may differ from the movement of the microscope. The difference is due to the refraction of light between the cover slip and the immersion medium of the lens. So the factor is usually the inverse of the index of refraction between the tissue and the lens immersion medium.
Under normal circumstances the predefined values for air, oil, and water immersion lenses can be used. But there are circumstances in which the predefined settings should not be used; contact us for information about unusual combinations of lenses and mounting media.
- Select User-Specified to enter your own correction factor.