(extended definition) Coating defect: small, shallow, bowl-shaped depressions in a coating film. These depressions frequently have drops, particles or bands of material at their centers and raised circular edges. Some common causes of cratering are: gel particles, oil droplets from air lines, and substrate contamination.
coating defect consisting of small, apparently uncoated, spots of coated plate consisting of a very thin film of coating that has been contaminated by oil, silicone, or other foreign matter. Eyeholing is similar to cratering, but with metal exposure in the crater.