Exposure and Lighting- U.S. Visa and Green Card Photo Requirements
- Over-exposure or under-exposure may render the photo unusable
- Three-point balanced lighting is strongly recommended (see Figure 1)
- Facial features should be clearly evident in the photo
- Lighting should be adjusted to avoid shadows on the face or background
- Diffuse sources of light, such as umbrella lights, are preferable to point sources
Over-exposure occurs when the image receives too much light; it results in a loss of resolution (very fine detail), more graininess and less detail in highlight areas. Under-exposure occurs when the image receives too little light; it results in loss of detail in the subject's shaded areas, which can become dark and featureless.
Exposure problems can be avoided by conforming to the recommended lighting arrangement (Figure 1) and using diffuse light sources of moderate lamp intensity.
Illuminating the background is best accomplished with a light source that spreads illumination evenly over a wide area.
Correct positioning of back-lighting, below the subject and radiating up, will reduce or remove shadows from the background without affecting the amount of light incident on the subject.
To avoid shadows on the face, the amount of light striking a subject's face from two sides, should be equal. In a balanced lighting arrangement, if one of the two light sources is of a lower intensity, move it closer to the subject to offset the difference in light intensity.
Overhead lighting can produce unwanted shadows on the face and should be avoided whether balanced lighting is used or not.