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Sep 4th 2025 | Posted by BoliOptics

How to Measure Your Microscope Eyepiece for the Correct Reticle Size

Buying the right microscope reticle starts with one critical step: measuring the internal diameter of your eyepiece. This guide walks you through exactly how to measure your eyepiece, determine compatibility, and choose the correct reticle size. ⚠️ Important Note: The number printed on your eypiece does not indicate the reticle size. Do not go off this number alone. For example: If you see 10X/22mm, the 22mm refers to the Field of View of the eyepiece, not the actual reticle size for the eyepiec …