Question

what does calibrating the microscope mean

Answer 1

In order to estimate the cell size during microscope investigation, microscope should be caliberated.

Calibration involves using a stage micrometer or scale.

Calibration is important in being able to measure the objects that are being observed.

Using just the lens doesn't give any reference to actual size of the object.

So using a micrometer on a slide allows for units to be placed, and gives correct measurements to be taken for the object.

Microscope calibration includes a comparison of the grid or scale on the eyepiece reticle with scale markings of a known dimensions on a stage micrometer.