a knob assembly graspable by a user, the knob assembly being manually rotatable about a rotational axis, to adjust an optical device setting;

a catch assembly defining a home position of the knob assembly whereat the catch assembly prevents rotation of the knob assembly in a clockwise or counterclockwise direction; and

wherein the catch assembly includes a button or other lock-release arranged to, responsive to a manually-applied force, disengage a catch member from a catch opening or recess to allow the knob assembly to be rotated, in the clockwise or counterclockwise direction and relative to the button or other lock-release, from the home position to an adjustment position.