Which method reduces sensitivity when applying dry developers?

• A. Immersion
• B. Electrostatic spraying
• C. Air suspension (storm chamber)
• D. None of the above

Answer: (A)

When applying dry developer, the coating needs to be a clean, fine, and uniform layer so the penetrant residues can be drawn out of any defects and reveal them clearly. Immersion introduces moisture, which causes the dry powder to clump, wash away, or stick unevenly to the surface. That disrupts the uniform distribution and the capillary action that makes flaws visible, so the sensitivity drops. In contrast, methods like electrostatic spraying or air suspension (storm chamber) deposit dry powder without introducing moisture, giving a consistent, finely distributed layer that preserves high sensitivity. Hence, immersion reduces the effectiveness of dry developer application.