Tiffen Filter Wheel 1 Fog Effect 1/2 Glass Filter - A natural fog causes lights to glow and flare. Contrast is lower, and sharpness may be affected as well. Tiffen Fog Filters mimic the effect of atomized water droplets in the air. For example, the effect of humidity in a tropical scene can be created or enhanced.
Note:
Tiffen Rectangular Fog Filters are available in grades 1/8 through 5 with 5 having the strongest effect
In their lower grades, these filters can take the edge off excess contrast and sharpness. Higher grades can create unnatural effects, such as in fantasy sequences
In general, however, the effect of a strong natural fog is not produced accurately by Fog Filters in their stronger grades: For that, Double Fog Filters are recommended