The 81A color correction filter warms the ambient light entering the lens by 200° Kelvin by adding "orange" to the overall exposure. The filter helps fine-tune the color or look of your scene to match your film's white balance.
The Hoya 81A filter is helpful when:
You are using daylight-balanced film and the light source is cooler than the traditional 5500° K and you need a specific amount of color correction to match your film type.
You want to add a slightly warmer look to your portraits.
You are shooting in overcast or shady conditions.
HOYA Multi-Coat (HMC) filters are recommended for enhancing the performance of today’s multicoated lenses. These popular filters minimize reflection, reduce flare and ghosting, and result in over 97% average light transmission.
Comparison of 81 Series Conversions:
Cooling Amount (in degrees Kelvin)
|Filter Factor:||1/2 stop|
|Glass Type:||Hoya Optical|
|Number of Multi-Coatings:||6 Total / 3 each side|
|Hardened Top Layer:||No|
|Frame Construction:||Standard Profile / Aluminum|
|Front Filter Threads:||Yes|