Microscopes with fine focus

Precise focus

— presence of system of exact focus in a microscope.

This feature means that two mechanical controls are responsible for focus — for preliminary focus (coarse focus) and for final fine tuning. This is a more expensive, but also more convenient option than having only one control (coarse focus). Fine tuning is especially relevant at high magnifications, when the working distance needs to be changed very precisely, literally in hundredths of a millimetre.