Introduction

Testing telescopes with infinity setting
A testing telescope with infinity setting is a telescope with a reticle in the focal plane of the telescope objective. The testing telescope is used to evaluate objects at infinity. A testing telescope with a collimator both set to infinity can be used to measure the angular direction of collimator to telescope.
The main components are:
- tube with objective
- adapter sleeve with reticle
- eyepiece

Testing telescopes with tube extension
(variable setting)
Testing telescopes with tube extension are used, if a variable distance setting(finite or infinite) is required to evaluate targets at finite distances or to check the distance setting of collimators. Testing telescopes with tube extension cannot be used as an alignment telescope.