What type of light is produced by using 100 watt spot bulbs with a plain filter for color contrast penetrants?

Using 100 watt spot bulbs with a plain filter for color contrast penetrants produces a high intensity narrow beam of light. This type of lighting is essential in Liquid Penetrant Testing because it enhances the visibility of the penetrant and any discontinuities in the test material.

A high intensity narrow beam focuses the light into a smaller area, which allows for more effective inspection of fine details and slight indications. The intensity ensures that even subtle color variations between the penetrant and the background can be detected, enabling inspectors to spot potential defects accurately.

This setup is preferred over other types of lighting, as a broad spectrum light would provide a wide range of wavelengths, making it difficult to differentiate between the colors of the penetrant and the surface. Similarly, diffuse light tends to scatter instead of providing a focused stream, which can obscure details. A low intensity wide beam, while covering a larger area, would not offer the necessary contrast and brightness required to effectively identify indications in the material under examination.