Methods for adjusting dither amplitude for MEMS mirrors in optical switches and optical switches employing such a method are disclosed. A dither amplitude of one or more MEMS mirrors may be adjusted in an optical switch having an input port, and an array of one or more MEMS mirrors that can be selectively optically coupled to one or more of N=3 optical input/output (I/O) ports. The MEMS mirrors are aligned mirrors to achieve nominal peak coupling at each of the N collimators. Digital-to-analog (DAC) settings for positioning mirrors in an open control loop as a function of the selected collimator are stored to a non-volatile memory. The DAC settings are used to determine a dither amplitude DITHER(x) for one of the MEMS mirrors positioned to couple optical signals to an output port at a position x. The optical switch apparatus may comprise N=3 optical input/output (I/O) ports, an array of one or more MEMS mirrors that can selectively reflect one or more spectral channels to one or more of the N ports, and a servo-control assembly in communication with said one or more of the MEMS mirrors. The servo control assembly includes memory containing digital-to-analog converter (DAC) settings for positioning each mirror in an open control loop as a function of a port position x. The servo control assembly is programmed to adjust dither amplitude of one or more of the MEMS mirrors using the stored DAC settings.