Methods for detecting contaminants on optical fiber connectors incorporate statistically based routines that include processing of one or more digital images to dynamically determine fiber locations and boundaries, detect contamination in fiber locations, dynamically detect ferrule boundaries, detect contamination in ferrule locations, and collect resulting data. Sequential masking and detection permits detection of contaminants in a first region non-coincident with a first mask image, and in a second region non-coincident with a second mask image. Dynamic determination of locations and boundaries for structures such as fibers, ferrules, and pins or pinhole features address limitations associated with static determination of locations and boundaries for these structures. Specific routines or routines are provided for single- and multi-fiber connectors, including single fiber connectors having physical contact and angled physical contact polishes.