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All necessary information about binoculars

All necessary information about microscopes: magnification, field of view, observed objects and much more

This useful article includes some of the most frequently asked questions about telescopes and astronomy

Learn everything you need to know about refractor telescopes to make the right choice

An interesting review on how such microscopes work, form the 3D image and in what fields they are applied

Learn what a numerical aperture is and how to choose a suitable objective lens for your microscope here