CTO, CTB and plus green in one chart
Full CTB (LEE 201) cools a light by 137 mired and takes a 3200 K tungsten lamp to about 5700 K, close to daylight. Going back, half CTO and an eighth (LEE 205 and 223) add 135 mired and bring 5600 K daylight to about 3190 K. Plus green works on a different axis, in CC, not mired.
The mired ruler
Each bar is how far one sheet moves a light, in mired. It is the same on any lamp.
Your lamp
- 204FULL CTO+1592120 K
- 2051/2 CTO+1092370 K
- 2061/4 CTO+642660 K
- 2231/8 CTO+262950 K
- 2181/8 CTB−183400 K
- 2031/4 CTB−353600 K
- 2021/2 CTB−784260 K
- 201FULL CTB−1375700 K
- 205 + 2231/2 + 1/8 CTO+1352230 K
Cutvey Meter · Gel chartDated October 2026 · CC BY 4.0
The chart
Download CSV (CC BY 4.0)| LEE | Gel | What the crew calls it | Shift | A 3200 K lamp becomes | 5600 K daylight becomes | Note |
|---|---|---|---|---|---|---|
| CTO: warms the light | ||||||
| 204 | Full C.T. Orange | Full CTO | +159 mired | 2120 K | 2960 K | Takes daylight past tungsten; 205 + 223 lands closer |
| 205 | Half C.T. Orange | 1/2 CTO | +109 mired | 2370 K | 3480 K | With 1/8 CTO (223), daylight to tungsten, one mired over |
| 206 | Quarter C.T. Orange | 1/4 CTO | +64 mired | 2660 K | 4120 K | |
| 223 | Eighth C.T. Orange | 1/8 CTO | +26 mired | 2950 K | 4890 K | The smallest warm step in the book |
| CTB: cools the light | ||||||
| 218 | Eighth C.T. Blue | 1/8 CTB | −18 mired | 3400 K | 6230 K | The smallest cool step in the book |
| 203 | Quarter C.T. Blue | 1/4 CTB | −35 mired | 3600 K | 6970 K | |
| 202 | Half C.T. Blue | 1/2 CTB | −78 mired | 4260 K | 9940 K | |
| 201 | Full C.T. Blue | Full CTB | −137 mired | 5700 K | 24050 K | Tungsten to daylight, 3 mired bluer |
| Plus green and minus green | ||||||
| 244 | LEE Plus Green | Full plus green | CC 30 green | not a kelvin gel | not a kelvin gel | Puts green on a lamp so it sits with tubes |
| 245 | Half Plus Green | 1/2 plus green | CC 15 green | not a kelvin gel | not a kelvin gel | |
| 246 | Quarter Plus Green | 1/4 plus green | CC 7.5 green | not a kelvin gel | not a kelvin gel | |
| 247 | LEE Minus Green | Full minus green | CC 30 magenta | not a kelvin gel | not a kelvin gel | Takes green out of tubes and green-leaning LEDs |
| 248 | Half Minus Green | 1/2 minus green | CC 15 magenta | not a kelvin gel | not a kelvin gel | |
| 249 | Quarter Minus Green | 1/4 minus green | CC 7.5 magenta | not a kelvin gel | not a kelvin gel | |
Mired shifts are LEE Filters' published values, the same table the app uses. Rosco's equivalents differ by a few mired, so from a Rosco book read a row as a strength, like half CTO. Green and magenta are LEE's nominal CC strengths; the app gives them as a rough hint only.