The Tiffen Filter Wheel 1 Ultra Contrast 4 Filter works by using the ambient light surrounding the image area as well as the light in the actual image area itself. It lowers contrast uniformly, with little or no loss of sharpness throughout the scene, even when there are varying degrees of brightness within the image.
Shadow areas are opened up, revealing more detail, but without any flare or halation from direct light sources or bright reflections. Works similar to a Tiffen Low Contrast filter but reduces contrast throughout the entire image whereas a Low Contrast filter will only open the shadows.
Tiffen - making hard-to-shoot images possible!
Note:
Tiffen Ultra Contrast filters are available in grades from 1/8 through 5, with 5 having the greatest effect
Bright lights or sunlight create problems when the ratio between the highlight and shadow areas is beyond the latitude of the film; If you expose for the highlights, the shadows appear without detail; If you expose for the shadows, the result is washed-out, overly bright highlights
Contrast reduction is achieved by lightening shadows without overexposing highlights or by darkening highlights without darkening shadows further
Even direct shooting into the sun produces no flare or halation