Coarse Focus

∞ generated and posted on 2016.01.14 ∞

Initial means of focusing a microscope which brings the specimen roughly but not necessarily fully into focus.

Focus dials typically will be differentiated into two types, with the larger dial associated with coarse focus. One's initial efforts to bring a specimen into focus will involve movement of the coarse focus. See also fine focus.

Coarse Focus

Figure legend: The coarse focus is adjusted using a dial that typically can be found to the outside of the fine focus dial. This dial also is closer to the body of the microscope than the fine focus dial.

Key to using a microscope is finding and learning how to operate the focus dials. Note that when you are attempting to focus in on a specimen, one "trick" you can use to make sure that you are focusing on the intended object is to move the specimen slightly using the mechanical stage adjustments. If what you are looking at moves about then at least you can be reasonably certain that you have focused in on something that is associated with the slide. This ideally will be the specimen, though it is up to you to make sure indeed that this is the case.