How to Adjust Coaxial Telescope

Telescopes are coaxial. Generally, reflective telescopes have strict requirements on coaxiality, while refractors have little requirements.

Reflecting telescope can adjust the coaxial. First of all, you can use LED flashlight for rough adjustment. After the rough adjustment is qualified, you can basically see it. If you need to connect a camera or a SLR camera, you need to fine-tune it.

Coarse adjustment: Take off the lamp cup of LED flashlight and turn on the flashlight. There is only one light spot, which is equivalent to a point light source. Put it in the eyepiece interface position. At this time, the telescope will project a big light spot and project this light spot on the distant wall. First, adjust the secondary mirror to make the flashlight light project on the primary mirror, and then adjust the screw of the primary mirror to make the shadow of the secondary mirror bracket evenly divide the light spot. Basically, it will do.

If fine adjustment is needed, you need a collimator, or adjust the base screw of the main mirror against the stars in the sky, which requires great patience. When the optical axis is completely positive, the diffraction halo around the star point can be seen. After adjustment, with the change of temperature, the optical axis will shift, so the reflection telescope photography is more troublesome.

It doesn't matter visually. The eyes can't tell the difference at all.