Section 5.1.2.2.1. Microscope

Perhaps the single most important piece of equipment for examining and mounting crystals is a binocular dissection microscope. This should have variable zoom capabilities, and there should be sufficient distance (e.g. 5–10 cm) between the objective lens of the microscope and the microscope stage to accommodate the necessary equipment and allow manipulation of the crystals and solutions. A magnification of between 10 and 40 times is probably best in practice. It is also important to ensure that the light source of the microscope is not so intense that it heats the microscope stage, thereby damaging the macromolecular crystals. If the microscope is fitted with crossed polarizers, the quality of the crystals can be assessed.