Which magnifications are used to enable macro and micro indications?

• A. 1-2x macro and 2-5x micro
• B. 100-200x macro and 200-500x micro
• C. 50-100x macro and 100-500x micro
• D. 5-20x macro indication and 20-100x micro indication

Answer: (D)

In liquid penetrant testing, you use different magnifications to see flaws at different sizes. Large surface indications are best seen with lower magnification, while very small, hairline indications require higher magnification to resolve.

Macro indications are typically examined around 5–20x. This range is enough to reveal broad, obvious surface features without needing specialized equipment.

Micro indications, such as fine cracks or tiny porosity, need more zoom to be distinguished, commonly in the 20–100x range. At these higher magnifications, small details become clear and can be evaluated properly.

So, using 5–20x for macro and 20–100x for micro aligns with how inspectors progressively magnify to detect both large and small surface indications, making that combination the best choice.