How to Correct for Spectral Errors of Popular Light Sources

Apogee quantum sensors accurately quantify the amount of photosynthetic light striking a surface in units of µmol m-2s-1. There are, however, certain factors that can introduce varying small errors into these measurements. One of these factors,spectral error,occurs when measuring a light source that has a different spectral output than the light used to calibrate the sensor. This error occurs because no quantum sensor can perfectly match the ideal quantum response, which is defined as an equal response to all wavelengths of light between 400 and 700 nm. When measuring certain light sources with our quantum sensors, an even higher level of accuracy can be achieved by applying post-measurement correction factors according to the chart below.

可以使用波长相关的计算可以近似光谱误差,该计算考虑了量子传感器的光谱响应,校准光源的光谱输出和测量光源的光谱输出。下表显示了许多不同流行灯源的计算理论谱误差和相应的校正因子。频谱误差相对于每个传感器的校准源计算(SQ-110被校准为清晰的太阳光,SQ-120和SQ-500被校准为4100K冷却的白色荧光T5灯)。

To correct for spectral error multiply your measured value by the correction factor (CF) associated with your light source. For example, if you are using an SQ-120 under a Blue LED (448nm), which has a spectral error of -12.7 and a CF of 1.15, and you measured 115 µmol m-2s-1, you would multiply your measurement of 115 µmol m-2s-1by the CF 1.15 to get 132.3 µmol m-2s-1(115 x 1.15 = 132.3).

SQ-110 correction factors apply to sun calibrated models SQ-110, 212, 214, and 215, and models SQ-420, MQ-100, 200, and 210 when in SUN setting.

SQ-120 correction factors apply to electric calibrated models SQ-120, 222, 224, and 225, and models SQ-420, MQ-100, 200, and 210 when in ELEC setting.

SQ-500 correction factors apply to models SQ-500 and 520, and MQ-500, 501, and 510.

This information is also available as aninteractive tool, which allows users to upload their own lighting spectrum.

Light Source Spectral Graph
(Click to Enlarge)

光谱误差
SQ-110
(太阳)

Correction Factor
SQ-110
(太阳)

光谱误差
SQ-120
(ELEC)

Correction Factor
SQ-120
(ELEC)

光谱误差
SQ-500
(全谱)

Correction Factor
SQ-500
(全谱)

Agro Ceramic Metal Halide Agro Ceramic Metal Halide Spectrum 0.0 1.00 -16.3 1.19 -1.8 1.02
Apache W LED Apache W LED Spectrum 15.8 0.86 -0.8 1.01 -0.5 1.01
蓝色LED(448nm) 蓝色LED(448nm)Spectrum 4.2 0.96 -12.7 1.15 0.8 0.99
CF GE 45 W CF GE 45 W Spectrum 16.6 0.86 -0.5 1.01 -0.9 1.01
CF Sylvania 30 W CF Sylvania 30 W Spectrum 12.3 0.89 -3.8. 1.04 0.0 1.00
CWF T5 Sylvania. CWF T5 Sylvania.Spectrum 16.9 0.86 0.0 N/A 0.0 N/A
Light Source Spectral Graph
(Click to Enlarge)

光谱误差
SQ-110
(太阳)

Correction Factor
SQ-110
(太阳)

光谱误差
SQ-120
(ELEC)

Correction Factor
SQ-120
(ELEC)

光谱误差
SQ-500
(全谱)

Correction Factor
SQ-500
(全谱)

CWF T8 Sylvania CWF T8 Sylvania Spectrum 16.6 0.86 -0.5 1.01 0.2 1.00
CWF T12 Sylvania CWF T12 Sylvania Spectrum 15.5 0.87 -1.6 1.02 0.3 1.00
翻转陶瓷金属卤化物 翻转陶瓷金属卤化物Spectrum 10.9 0.91 -14.6 1.17 -0.3 1.00
Green LED 524nm 绿色LED 524nm光谱 24.9 0.80 7.0 0.93 3.0 0.97
High Pressure Sodium High Pressure Sodium Spectrum 17.7 0.85 0.5 1.00 0.0 1.00
Illumitex RB LED Illumitex RB LEDSpectrum -36.0 1.56 -45.2 1.82 -2.6 1.03
Light Source Spectral Graph
(Click to Enlarge)

光谱误差
SQ-110
(太阳)

Correction Factor
SQ-110
(太阳)

光谱误差
SQ-120
(ELEC)

Correction Factor
SQ-120
(ELEC)

光谱误差
SQ-500
(全谱)

Correction Factor
SQ-500
(全谱)

Incandescent 40 W 白炽灯40 W频谱 -15.8 1.19 -28.5 1.40 -7.3 1.08
Incandescent 100 W 白炽灯100 W频段 -17.0 1.20 -29.5 1.42 -7.6 1.08
Kessil Tuna Blue Kessil Tuna Blue Spectrum 11.9 0.89 -4.7 1.05 1.7 0.98
LI 1800-02 Calibrator LI 1800-02校准谱 -10.6 1.12 -24.1 1.32 -5.7 1.06
Lighting Science RB LED Lighting Science RB LED Spectrum -48.4 1.94 -55.8 2.26 -3.4 1.04
Lighting Science RW LED Lighting Science RW LED Spectrum -43.4 1.77 -51.5 2.06 -3.0 1.03
Light Source Spectral Graph
(Click to Enlarge)

光谱误差
SQ-110
(太阳)

Correction Factor
SQ-110
(太阳)

光谱误差
SQ-120
(ELEC)

Correction Factor
SQ-120
(ELEC)

光谱误差
SQ-500
(全谱)

Correction Factor
SQ-500
(全谱)

Metal Halide 金属卤化物光谱 13.2 0.88 -4.3 1.04 -5.7 1.06
Quartz Halogen 石英卤素Spectrum -10.5 1.12 -24.0 1.32 -5.7 1.06
RB LED RB LED Spectrum 19.3 0.84 2.2 0.98 -1.5 1.02
Red LED 635 nm RED LED 635nm Spectrum 21.7 0.82 -4.4 1.05 -2.0 1.02
Reflected Conifer Reflected Conifer Spectrum 5.5 0.95 -11.3 1.13 -2.2 1.02
Reflected Deciduous Reflected Deciduous Spectrum 4.9 0.95 -11.9 1.14 -2.0 1.02
Light Source Spectral Graph
(Click to Enlarge)

光谱误差
SQ-110
(太阳)

Correction Factor
SQ-110
(太阳)

光谱误差
SQ-120
(ELEC)

Correction Factor
SQ-120
(ELEC)

光谱误差
SQ-500
(全谱)

Correction Factor
SQ-500
(全谱)

Reflected Grass Reflected Grass Spectrum 5.7 0.95 -10.9 1.12 -2.2 1.02
RGB LED RGB LED Spectrum 20.3 0.83 3.0 0.97 -0.8 1.01
Sun Clear 太阳清晰的光谱 0.0 N/A -14.8 1.17 -2.2 1.02
Sun Cloudy 太阳多云谱 1.4 0.99 -14.4 1.17 -1.7 1.02
在苜蓿冠层下 在苜蓿冠层下Spectrum 6.4 0.94 -11.9 1.14 -1.7 1.02
Under Maple Canopy Under Maple Canopy Spectrum 6.8 0.94 -11.8 1.13 -0.9 1.01
Light Source Spectral Graph
(Click to Enlarge)

光谱误差
SQ-110
(太阳)

Correction Factor
SQ-110
(太阳)

光谱误差
SQ-120
(ELEC)

Correction Factor
SQ-120
(ELEC)

光谱误差
SQ-500
(全谱)

Correction Factor
SQ-500
(全谱)

Under Pine Canopy 在松树冠层谱下 5.3 0.95 -12.9 1.15 -0.4 1.00
Under Wheat Canopy Under Wheat Canopy Spectrum 6.4 0.94 -11.7 1.15 -1.1 1.01
Valoya RW LED Valoya RW LED Spectrum -16.0 1.19 -28.0 1.39 -6.0 1.06
WWF LED WWF LED Spectrum 6.0 0.94 -9.2 1.10 -1.9 1.02
2 Actinic, 2 Blue Plus 2 Actinic 2 Blue Plus Spectrum -2.3 1.02 -16.8 1.20 -3.0 1.03
3 T5, 1 Actinic 3 T5 1 Actinic Spectrum 9.2 0.92 -7.0 1.08 -2.0 1.02
4 Actinic 4型光谱 -16.0 1.19 -28.5 1.40 -10.0 1.11
4 Blue Plus 4 Blue Plus Spectrum 7.4 0.93 -8.5 1.09 -3.0 1.03