Digital Zoom vs Optical Zoom: What’s the Difference?

What is the difference between digital zoom vs optical zoom for an imaging system? This is a question that some users ask; while all experts agree that optical zoom is much better and more effective, some may have a hard time explaining why.

Imaging systems (thermal, visual, or other spectral areas) provide visual information on distant targets, beyond what the eye can see. To gather enough information to perform imaging tasks such as detection, recognition, and identification, the imager must provide an appropriate field-of-view to allow enough magnification so that the user can see the necessary details. To increase magnification (make the image appear ‘bigger’), the field-of-view (FoV) of the system must be decreased. Here’s where some confusion begins to take place.