This hoya green x1 11 filter is ideal for scenes where it is important to differentiate the green tonal values in black and white photography the hoya 67mm hmc green x1 filter transmits a relatively narrow wavelength band centred around light in the green spectrum and is named after the wavelength at which their transmittance attains the maximum value multicoated to minimize reflection at the filter surfaces which reduces flare and ghosting especially suited to landscape photography