White balance
White balance is used to match the colour of the image taken by the camera to the colour temperature of the ambient light. The aim is to reproduce colours more realistically. Without white balance, which is often done automatically in digital cameras, the image can look fake.
Wide-Angle Lens
A lens that has a shorter focal length and a wider field of view (includes more subject area) than a normal lens.
Window
In a well-cut faceted gem, the pavilion facets should reflect light back out the top or table of the stone. If the facets are cut below the critical angle for the particular material, light will pass right through the stone instead of being reflected back toward the eye. This results in the gem will lacking in sparkle and brilliance.
