A product testing apparatus, comprising: - a microscope having a microscopic imaging device configured to capture one or more images indicative of a sample having a paint substrate coating applied to a substrate; and - at least one data processing system having a processor, one or more non-transitory processor readable medium, and processor executable instructions stored on the non-transitory processor readable medium that when executed cause the processor to: - receive the one or more images captured by the microscopic imaging device; - process the one or more images to create one or more filtered images by filtering lighting variations in pixels of the one or more images to identify the differences in contrast and thereby identify one or more objects of interest which are bubbles in the one or more images of the paint substrate coating, wherein the one or more filtered images contain the one or more objects of interest, a background and one or more other objects, which are grit, dirt, foreign objects or other imperfections; - differentiate between the one or more objects of interest and the one or more other objects based upon the shape of groups of pixels having the same value; - quantify the one or more objects of interest; and - generate a signal indicative of the quantification of the one or more objects of interest. - a microscope having a microscopic imaging device configured to capture one or more images indicative of a sample having a paint substrate coating applied to a substrate; and - at least one data processing system having a processor, one or more non-transitory processor readable medium, and processor executable instructions stored on the non-transitory processor readable medium that when executed cause the processor to: - receive the one or more images captured by the microscopic imaging device; - process the one or more images to create one or more filtered images by filtering lighting variations in pixels of the one or more images to identify the differences in contrast and thereby identify one or more objects of interest which are bubbles in the one or more images of the paint substrate coating, wherein the one or more filtered images contain the one or more objects of interest, a background and one or more other objects, which are grit, dirt, foreign objects or other imperfections; - differentiate between the one or more objects of interest and the one or more other objects based upon the shape of groups of pixels having the same value; - quantify the one or more objects of interest; and - generate a signal indicative of the quantification of the one or more objects of interest. - receive the one or more images captured by the microscopic imaging device; - process the one or more images to create one or more filtered images by filtering lighting variations in pixels of the one or more images to identify the differences in contrast and thereby identify one or more objects of interest which are bubbles in the one or more images of the paint substrate coating, wherein the one or more filtered images contain the one or more objects of interest, a background and one or more other objects, which are grit, dirt, foreign objects or other imperfections; - differentiate between the one or more objects of interest and the one or more other objects based upon the shape of groups of pixels having the same value; - quantify the one or more objects of interest; and - generate a signal indicative of the quantification of the one or more objects of interest.