Used primarily for black and white photography. XO is highly effective for outdoor portraits because red is rendered dark while green appears lighter.
Great for correcting skin tones, bringing out facial expressions in close-ups and emphasizing the feeling of liveliness. X1 is highly effective for indoor portraits under tungsten lighting.
FOR COLOR FILM:
These filters, such as K2 (Yellow), G (Orange), 25A (Red), X0 (Yellow/green) and X1 (Green) are primarilly designed for use with Black & White film. However, they can be used with color film to produce special color effects.
HMC (HOYA MULTI COATED)
These popular filters are renowned for their ability to minimise reflection at the filter surfaces which reduces flare and ghosting. The result is an average light transmission of over 97%, giving sharp contrast and well balanced color. HOYA HMC filters are recommended for enhancing the performance of today's multicoated lenses.