Function

• Crystallographic images help us understand how atoms are arranged in a sample.atom_grid image by Sergey Tokarev from Fotolia.com
  
  Electron microscopes may be used to study the topography, morphology, composition and crystallographic information of a sample. The protocol you use will vary based on the sample you're working with, the microscope you're using, the stains used on the sample and the type of information you are looking for.
  
  

Types

• There are two types of electron microscopes: transmission electron microscopes (TEMs) and scanning electron microscopes (SEMS). You would use two different protocols to study the same sample using two types of electron microscopes.
  
  

Time

• According to The Huck Institutes, experiments using TEMs take between a few days to a week of specimen prep time plus several hours of microscope study. SEM experiments take two or three days in total, and much of this time is devoted to specimen prep as well.