Apogee Instruments - Model S2-131) - RED - FAR-RED SENSORS (S2-131)

Apogee Red - Far-Red sensors combine two photodetectors designed to measure wavelength ranges and peaks that approximate phytochrome absorption. The red / far-red ratio can be calculated from these measurements. Red and far-red wavelengths are of particular interest because they influence photosynthetic and morphogenic activity. Phytochrome pigments sensitive to varying ratios of red and far-red light provide information to the plant about its light environment.