When gazing through a stereo zoom microscope or Zoom Stereoscopic Microscopes, the picture is three-dimensional or "stereo." The zoom feature on the microscope gives a variety of viewing options and is the single most important element to consider when purchasing a stereoscope. When zooming in on a microscopy sample, the zoom knob on a stereo microscope gives magnification within a wide range and eventually allows the ability to observe every single magnification. The stereo zoom microscopes or Zoom Stereoscopic Microscopes provide rapid magnification changes from low to high. It allows you to observe a sample in its entirety, then focus and zoom in on a specific area of interest.