CTO-050 Color Temperature Orange (Warming) Filter
1/2 CTO colour-conversion filter shifting 5600 K toward 3800 K for seamless mixed-lighting balance in broadcast, film, and architectural applications.
- Colour shift direction: Warming (5600 K → 3800 K)
- Mired shift: +67 Mired
- Correction strength: 1/2 CTO
- Average transmittance: ~57.8 % T (visible range)
- Peak transmittance: ~95.3 % T near 744 nm
- Minimum transmittance: ~3.2 % T near 380 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-050 delivers a +67 Mired shift to move 5600 K light toward 3800 K. Its smooth spectral slope creates a natural warming effect, with about 57.8 % average visible transmittance and approximately 0.7 stops of light loss.
The ion-assisted hard-oxide coating is built for repeated handling, heat, and cleaning.
Best suited for:
Moderate warming when daylight and tungsten need to blend, especially for interview lighting, event rigs, and warmer skin tones.
Description
CTO-050 provides a full CTO conversion with its 50 % crossover at 553 nm and outstanding long-wavelength performance. NIR averages 93.4 %, peaking at 95.3 % at 744 nm, while red averages 87.3 %. The transition is clean: UV-violet is suppressed below 18 %, blue below 20 %, and transmission rises smoothly through green (32.8 %) and yellow (79.6 %) to the high warm plateau. The profile combines standard full CTO colour shift with particularly strong NIR throughput.
Key Advantages
- Full CTO crossover at 553 nm with NIR avg 93.4 % - delivers standard full-CTO conversion with the highest NIR throughput in this crossover range.
- Peak of 95.3 % at 744 nm - maintains excellent efficiency in the far red and NIR bands.
- Clean UV-blue suppression - provides < 20 % in violet and blue for a convincing full-CTO conversion.
- Hard-oxide durability - ion-assisted coating withstands high lamp 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 theatrical lighting - provides a standard full-CTO conversion for daylight-to-tungsten matching with excellent output efficiency.
- Film and broadcast production - converts daylight fixtures to tungsten balance with minimal light loss.
- Combined visible-NIR imaging - warms the visible output while maintaining near-perfect NIR transmission for day-night camera systems.
- Architectural lighting - transforms cool-white LED sources into warm 2700-3200 K equivalents for residential and hospitality applications.
- LED fixture colour correction - delivers full CTO conversion as a durable, permanent replacement for disposable gel sheets.
Need prototypes in days or production volumes next quarter? CTO-050 filters can be coated, diced, and shipped to your exact specifications.
FAQ
CTO-050 FAQ
What is CTO-050 and what is it used for?
CTO-050 is a Color Temperature Orange Filter - Full CTO with High NIR (T50% = 553 nm). CTO-050 is a full-CTO conversion filter with a 50 % crossover at 553 nm and exceptionally high NIR transmission. With violet at 10.7 % and blue at 11.9 %, this filter provides strong blue suppression while maintaining a smooth warm passband through yellow (61.4 %), orange (84.4 %), and red (92.2 %), reaching 95.5 % in the NIR at 800 nm. Common uses include Stage and theatrical lighting, Film and broadcast colour correction, Infrared and NIR illumination, and Photography warm filtration.
What are the key optical specs of CTO-050?
Key published specs for CTO-050 include Colour shift direction: Warming (5600 K → 3200 K); Mired shift: +131 Mired; Correction strength: Full CTO; Average transmittance: ~51.6 % T (visible range); Peak transmittance: ~95.5 % T near 800 nm.
What applications is CTO-050 best suited for?
CTO-050 is commonly used for Stage and theatrical lighting, Film and broadcast colour correction, Infrared and NIR illumination, and Photography warm filtration. Stage and theatrical lighting - provides the standard full-CTO conversion from daylight to tungsten colour balance.
Can CTO-050 be customized for size, substrate, or coating requirements?
KUPO lists the construction for CTO-050 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-050?
The ion-assisted hard-oxide coating is built for repeated handling, heat, and cleaning.
