Glass Black Mist 1/4 Filter for 4x5.65 Matte Box — K&F (SB10339)

The Glass Black Mist 1/4 Filter for 4x5.65 Matte Box by K&F is an optical diffusion filter engineered for matte box systems that accept 4x5.65 inserts. It is made from optical-grade glass and introduces a subtle veil over highlights and specular reflections, reducing contrast and producing a controlled bloom effect. The filter is suitable for filmmakers and videographers seeking gentle highlight roll-off, softened skin tones and a cinematic, filmic look without heavy diffusion artifacts.

Advantages

This Black Mist 1/4 filter reduces peak highlights while retaining overall image sharpness, allowing detail to remain visible even as highlights bloom. Manufactured to fit 4x5.65 matte boxes, the filter provides consistent optical characteristics across the frame and minimal color cast. Its glass construction offers stable optical performance and durability compared with resin diffusers, making it suitable for repeated professional use on camera rigs and interview setups.

Suitable for

• Professional and indie filmmaking where controlled highlight bloom is required
• Portrait video and interview shoots to soften skin textures
• Music videos and narrative scenes seeking a filmic glow
• On-rig use with matte boxes from manufacturers like Tilta and SmallRig

Key specifications

• Filter type: Black Mist diffusion (1/4 strength)
• Material: Optical glass
• Size/format: 4x5.65 inch matte box insert
• Effect: Reduced contrast with highlight bloom and softened highlights

How to use

Insert the filter into a compatible 4x5.65 matte box slot and secure it according to your matte box manufacturer’s instructions. Position the filter in front of the lens as part of your filter stack; for stronger diffusion you may combine it with other creative or neutral density filters, taking care to avoid vignetting with wide-angle lenses. Monitor exposure and white balance when introducing the filter, as the subtle light scattering can affect perceived contrast and highlight rendering.

Usage recommendations

Use the Black Mist 1/4 when you want a natural, controlled bloom without losing subject detail. It works well at moderate apertures and when highlights would otherwise clip; avoid stacking multiple strong diffusers unless a pronounced effect is desired. Clean with a soft blower and microfibre cloth to preserve the optical coating and glass surface.