Moose Warm Polarizer filters, an exclusive collaboration between Hoya and respected wildlife photographer and conservationist B. Moose Peterson of Wildlife Research Photography, are a combination of a polarizer and an 81A warming filter.
These are light balancing filters used to increase the color temperature slightly for a cooler (bluer) tone. Corrects the tendency toward reddish tones. These series filters are also used to prevent the reddish tones in early morning or late evening light for natural skin tones.
Do not mix 81 and 82 series filters since they cancel out each other.