Which method is NOT a procedure to recover original serial numbers?

The correct response indicates that digital imaging analysis is not a recognized procedure for recovering original serial numbers on objects. Serial numbers may become obscured or altered due to various factors like wear, corrosion, or intentional tampering. The other methods listed are specifically designed to enhance or recover these numbers when they cannot be easily identified.

Magnaflux, for instance, is used primarily in magnetic particle inspection to identify defects in ferrous materials and can help reveal serial numbers when applied correctly. Chemical etching is a process that utilizes chemical solutions to reveal hidden serial numbers by reacting with the metal surface. Ultrasonic cavitation employs high-frequency sound waves to create microscopic bubbles in a liquid that can help dislodge contaminants and potentially reveal underlying serial numbers on a surface.

In contrast, while digital imaging analysis may be useful for many aspects of forensic science, such as analyzing photographs or enhancing images, it does not physically recover original serial numbers. Instead, this method is better suited for visual interpretation rather than the actual recovery of physical data from surfaces. Therefore, it is distinct from other methods that apply physical or chemical means specifically aimed at uncovering serial numbers.