A system and method for detecting defects in TFT-array panels is provided that improves defect detection accuracy by adjusting the thresholding parameters used to classify defective pixels when the number of defects reported by a TFT-array testing system exceeds a predetermined critical number. In a preferred embodiment, the thresholding parameters are adjusted until the number of reported defects is less than or equal to the predetermined critical number. The predetermined critical number represents a threshold number for determining if the number of reported defects is abnormally high. Reducing the number of reported defects to a number equal to or less than the predetermined critical number will decrease the operation time of the TFT-array repair equipment, because of the reduced number of potential defects it will be required to handle, and will also result in the TFT-array testing system reporting a smaller number of potential defects, with the potential defects that are reported having a higher probability of being real defects.