Pick up your microscope from the trolley and carry it carefully. Most microscopes are broken because they are dropped. Remove the plastic cover - dust and dirt are the enemy of your microscope. Don't put your fingers on the lenses and remember to cover it again after use. Turn the objective lenses so that the lowest power lens is "clicked" into ... An achro- matic single system may con- sist of two or three lenses, and a three or four system objective may consist of as many as seven or eight lenses. The systems are called in their order : anterior or front, mid- dle and posterior. When one consists of two lenses it is called a doublet, when of three lenses a triplet.
on a given microscope, the numerical apertures of the condensor and low power objective lenses are 1.25 and 0.25, respectively, you are supplied with a filter that selects a wavelength of 520 nm. What is the limit of resolution on this microscope? Will you be able to distinguish two points that are 330 nm apart as being separate, or will they blur?