CTO-011 Color Correction Filter
⅜-CTO glass filter: trims blue to ~20 % @ 400 nm, rises past 60 % @ 580 nm, and tops 90 % beyond 665 nm—warming daylight units ~1300–1400 K for tungsten-friendly ambience.
- Blue dip: ≈ 20 % T @ 400 nm • ≈ 30 % T @ 500 nm
- Amber ramp: 60 % T @ 580 nm → > 90 % T > 665 nm
- CCT shift: −1300 – 1400 K (≈ ⅜-CTO)
- Red plateau: ≥ 90 % T through 665–780 nm
- Construction: Ion-assisted hard-oxide; 5–450 mm, 0.21–3.8 mm thick
- Custom options: AOI tuning, ripple smoothing, rapid prototypes
Learn more
CTO-011 delivers a richer amber than CTO-010—about a ⅜-CTO correction—
dropping a 5600 K daylight fixture to roughly 4200 K. Transmission bottoms near 20 %
in the deep violet (~400 nm), rises past 30 % at 500 nm, crosses 60 % near 580 nm,
and exceeds 90 % beyond 665 nm before tapering through the far red. The gentle, notch-free
slope avoids green spikes and keeps output high.
KUPO coats Borofloat®, soda-lime, Schott D263 T, or Corning Eagle XG substrates cut
to any outline—from 5 mm chips to 450 mm plates—with thicknesses of 0.21–3.8 mm,
and can ship prototypes in about two weeks.
Typical uses: warming daylight LEDs/HMIs for film sets, adding inviting amber to
stage front-light, subtle warmth in museum or retail spots, golden-hour flash modifiers,
and machine-vision tasks needing modest blue suppression with strong red contrast.
Description
CTO-011 delivers a slightly deeper amber than CTO-010—about a ⅜-CTO correction—moving a 5600 K daylight source to roughly 4200 K. The curve bottoms out near 20 % around 400 nm, rises gradually past 30 % at 500 nm, crosses 60 % at 580 nm and crests above 90 % beyond 665 nm, giving cameras and eyes a richer, tungsten-like warmth while still preserving plenty of output.
Key advantages
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⅜-CTO colour shift – Drops daylight fixtures into the cosy 4000–4300 K window without a tell-tale green spike.
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High red efficiency – > 90 % transmission from 665 nm to 780 nm retains punch and fixture efficacy.
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Smooth spectral ramp – No harsh notches; gels blend cleanly with practical tungsten lamps and skin tones.
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Durable all-glass build – Hard oxide coatings shrug off heat, UV and scratches far better than plastic alternatives.
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Made-to-order formats – Any outline from 5 mm to 450 mm, 0.21 – 3.8 mm thick on Borofloat®, soda-lime, Schott D263 T or Corning Eagle XG.
Typical applications
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Broadcast & film – Warm LED panels or HMIs to mix seamlessly with tungsten practicals.
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Stage front-light – Add inviting amber to performers while keeping beam intensity high.
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Museum & retail lighting – Introduce subtle warmth that flatters objects without oversaturating colours.
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Flash modifiers – Fine-tune strobes for golden-hour looks or mixed-light scenes.
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Machine-vision – Enhance red-channel contrast where only moderate blue reduction is desired.
Need quick prototypes or production quantities? CTO-011 filters can be coated, diced and shipped to your exact spec—fast.
