Pinholes: Why am I seeing tiny specks of white light bleeding through my metal gobo?

Over long periods of continuous exposure to high-wattage lamp arcs, the concentrated heat can cause minor scaling or degradation on low-grade steel plates. If you are seeing micro-specks of light bleeding through, it’s a sign the metal is breaking down. For permanent, long-term installations in high-heat environments, upgrading to a glass gobo completely eliminates pinholing.