An optical mount system that may be adjusted by a variety of devices and methods. In some cases, a post collar assembly may be configured to engage a collar coupling surface of a post holder body such that the post collar engages the collar coupling surface in indexed and predetermined angular positions. In some cases, a base of a post holder body may be configured to accept a secondary base element in the form of a mounting adapter which may be releasably secured the base to provide additional stiffness for the mounting of the base to a reference surface.