Tiffen 405WSFX4 40.5mm Warm Soft/FX 4 Filter

The Tiffen 40.5mm Warm Soft/FX 4 filter is designed for photographers and videographers who want to achieve a warm, softened aesthetic directly in-camera rather than relying entirely on post-processing. It merges two distinct optical effects into one filter: the Soft/FX diffusion, which gently spreads highlights and reduces the appearance of fine skin texture, and the 812 warming element, which adds a subtle warm shift that helps unify and flatter varied skin tones. This two-in-one approach means fewer filters on the lens, reduced vignetting risk, and a simpler kit for portrait sessions.

Built using Tiffen's ColorCore process, the filter effect is sandwiched between two layers of optical glass, ensuring that the warming and diffusion properties remain consistent across the entire surface and are protected from moisture and physical wear at the edges. The grade 4 strength sits near the top of the Soft/FX range, delivering a clearly visible diffusion that smooths skin and creates a dreamy glow around highlights. This makes it particularly effective for close-up portraiture, beauty work, and bridal photography, though it is less suited to genres where edge-to-edge sharpness is paramount. The 40.5mm size is relatively uncommon and primarily fits compact mirrorless lenses and select vintage optics.