Assertion: reflecting telescope's mirror | /r/HasProperty | centered in the focuser drawtube
Facets:
Source sentences:
text: The secondary mirror itself should be centered in the focuser drawtube, in the direction parallel to the length of the telescope.
text: When the secondary mirror is centered in the focuser draw-tube, rotate the secondary mirror holder until the reflection of the primary mirror is as centered in the secondary mirror as possible.