W4 color correction filter warms the ambient light entering the lens by 500° kelvin (+40 mired shift) by adding light amber color to the overall exposure. This filter helps fine-tune the color or look of your scene to match your film's white balance or creative vision.

The Hoya W4 filter is helpful when:

• You are using daylight-balanced film and the light source is colder than the desired look and you need a specific amount of color correction to match your film's color balance (5500°K). Great on strong overcast days or when you subject is in the heavy shade.

• When shooting portraits and you want to give the skin tone a sun-kissed warm look.

• You are shooting at sunrise or sunset with daylight-balanced film (5500° K) and you want to a really warm looking scene.

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 C Series Filters: