81A (WARM FILTER)
These are light balancing filters used to decrease the color temperature slightly for a warmer (redder) tone. Corrects the tendency toward bluish tones. For example, the 81A should be selected when using tungsten Type B color film (3200°K) with photoflood lamps (3400°K) These filters can be used together.
"81" series are color corrective filters that 'warm' bluish tones. They are avaible in several strengths (A, B, C & EF) with 'A' being the mildest warming effect.
These filters offer both amateur and professional photographers HOYA's famous quality at reasonable prices. They have coatings applied to both surfaces to suppress reflection and increase light transmission. There are a few exceptions in the special effects range which, due to the special materials used in construction, do not have coatings applied.