CTO-032 Color Temperature Orange (Warming) Filter
3/4 CTO colour-conversion filter shifting 5600 K toward 3400 K for seamless mixed-lighting balance in broadcast, film, and architectural applications.
- Colour shift direction: Warming (5600 K → 3400 K)
- Mired shift: +100 Mired
- Correction strength: 3/4 CTO
- Average transmittance: ~52.4 % T (visible range)
- Peak transmittance: ~95.1 % T near 724 nm
- Minimum transmittance: ~9.7 % T near 437 nm
- Construction: Ion-assisted hard-oxide; 5 – 450 mm shapes, 0.21 – 3.8 mm thick
- Custom options: Intermediate Mired shifts, combined CTO+diffusion, custom sizes, rapid prototypes
Learn more
CTO-032 delivers a +100 Mired shift to move 5600 K light toward 3400 K. Its smooth spectral slope creates a natural warming effect, with about 52.4 % average visible transmittance and a low amount of light loss.
The ion-assisted hard-oxide coating is built for repeated handling, heat, and cleaning.
Best suited for:
Strong but not full warming when you want a natural blend between daylight and tungsten sources.
Description
CTO-032 has an unusual spectral shape for a CTO filter: a moderate violet shoulder (380 nm at 70 %), a deep suppression trough centred on green (495-570 nm at avg 21.4 %), and a strong red passband peaking at 95.1 % at 724 nm. The 50 % crossover at 632 nm defines the entry into the high-transmission zone. Blue wavelengths average 47.4 % - higher than expected for a deep CTO - owing to the persistent violet shoulder. The result is a warm filter with a green-suppression notch character rather than a clean longpass, producing a distinctive magenta-warm tonality.
Key Advantages
- 50 % crossover at 632 nm with peak of 95.1 % at 724 nm - delivers strong red-NIR throughput with high peak efficiency.
- Deep green suppression (avg 21.4 % at 495-570 nm) - removes the green band while preserving violet and blue shoulders, creating unique colour character.
- Distinctive magenta-warm tonality - combines warm red dominance with residual violet for a richer, more complex colour than standard CTOs.
- Hard-oxide durability - ion-assisted coating resists heat, humidity, solvents, and cleaning.
- Custom formats available - round, square, or free-form blanks from 5 mm to 450 mm, thickness 0.21-3.8 mm, on Borofloat®, soda-lime, Schott D263 T, or Corning Eagle XG substrates.
Typical Applications
- Stage and event lighting effects - creates a distinctive warm-magenta wash that differs from standard amber CTO tones for creative scene design.
- Film and photography colour effects - adds a unique warm-with-violet tonality for stylised portraiture or atmospheric location shoots.
- Green-suppression optical processing - removes the green band from broadband sources while maintaining violet and red, useful for fluorescence excitation filtering.
- Display and projection colour tuning - shapes the spectral output of white LEDs to suppress green excess and boost red, correcting colour rendering index (CRI).
- Machine vision with green rejection - suppresses green reflections or fluorescence while passing violet, blue, and red channels for multi-band inspection.
Need prototypes in days or production volumes next quarter? CTO-032 filters can be coated, diced, and shipped to your exact specifications.
FAQ
CTO-032 FAQ
What is CTO-032 and what is it used for?
CTO-032 is a Color Temperature Orange Filter - Notch-Shaped Deep Red (T50 % = 632 nm). CTO-032 has an unusual spectral shape for a CTO filter: a moderate violet shoulder (380 nm at 70 %), a deep suppression trough centred on green (495-570 nm at avg 21.4 %), and a strong red passband peaking at 95.1 % at 724 nm. The 50 % crossover at 632 nm defines the entry into the high-transmission zone. Common uses include Stage and event lighting effects, Film and photography colour effects, Green-suppression optical processing, and Display and projection colour tuning.
What are the key optical specs of CTO-032?
Key published specs for CTO-032 include Colour shift direction: Warming (5600 K → 3400 K); Mired shift: +100 Mired; Correction strength: 3/4 CTO; Average transmittance: ~52.4 % T (visible range); Peak transmittance: ~95.1 % T near 724 nm.
What applications is CTO-032 best suited for?
CTO-032 is commonly used for Stage and event lighting effects, Film and photography colour effects, Green-suppression optical processing, and Display and projection colour tuning. Stage and event lighting effects - creates a distinctive warm-magenta wash that differs from standard amber CTO tones for creative scene design.
Can CTO-032 be customized for size, substrate, or coating requirements?
KUPO lists the construction for CTO-032 as Ion-assisted hard-oxide; 5 – 450 mm shapes, 0.21 – 3.8 mm thick. Published custom options include Intermediate Mired shifts, combined CTO+diffusion, custom sizes, rapid prototypes. Custom formats available - round, square, or free-form blanks from 5 mm to 450 mm, thickness 0.21-3.8 mm, on Borofloat®, soda-lime, Schott D263 T, or Corning Eagle XG substrates.
What should I know about angle of incidence and durability for CTO-032?
The ion-assisted hard-oxide coating is built for repeated handling, heat, and cleaning.
