CTO-016 is a Color Temperature Filter designed to add a subtle, controlled warming shift while maintaining a smooth spectral response and natural rendering. It starts with moderate transmission in the blue region, then gradually increases through the green and into the red, allowing more long-wavelength energy to pass. This gentle slope produces a warm balance change that feels natural on camera and to the eye, without harsh cutoffs that can create color artifacts.
Key advantages
Subtle warming shift – nudges correlated color temperature warmer by slightly reducing blue energy relative to red.
Smooth spectral slope – avoids sharp transitions that can cause banding, unnatural hues, or channel artifacts.
Strong long-wavelength throughput – preserves reds and ambers for healthier skin tones and warmer highlights.
Stable, repeatable tuning – consistent response across the visible range supports repeatability across fixtures and batches.
Hard-oxide durability – ion-assisted coating options resist heat, humidity, solvents, and repeated cleaning.
Flexible formats (KUPO custom-made optical filters) – round, square, or complex blanks from 5 mm to 450 mm, 0.21–3.8 mm thick, on Borofloat®, soda-lime, Schott D263 T, or Corning Eagle XG glass.
Typical applications
Stage and architectural lighting – add a gentle tungsten-like warmth to LED and discharge sources while keeping output smooth.
Broadcast and studio fixtures – fine-tune correlated color temperature to match cameras, sets, or mixed lighting environments.
Film and photography – warm key or fill lights for flattering skin tones and consistent white balance.
Retail and exhibition lighting – enhance warm materials such as wood, textiles, and food displays while maintaining a natural look.
Optical systems needing light warming – introduce controlled warmth without introducing harsh spectral discontinuities.
Need prototypes fast or production volumes soon? CTO-016 filters can be coated, diced, and shipped to your exact specifications quickly, and because KUPO can custom-make optical filters, we can tune warming strength, substrate, thickness, and angle-of-incidence targets to match your light source and optical stack.