PAR meters are an important tool for growers and they provide useful data about the total amount of photosynthetic light being transmitted to the sensor. … Plants “see” light differently than humans do. Studies have shown that plants benefit from light wavelengths between 400 to 700 nanometers.

Why are PAR meters so expensive?

All PAR meters are made with a sensor that counts individual photons (“particles” of light). … Better filters and sensors typically cost more and so increase the price of the PAR meter. Because no filter material or sensor is perfect, these meters are calibrated to “average” light spectra, such as natural sunlight.

What is a PAR measurement?

PAR stands for Photosynthetically Available Radiation, which is light that falls into the 400-700nm spectral range. The unit for measuring par is micromoles per second, abbreviated as μmol/s. This unit indicates how many photons in the PAR spectral range fall onto the plant each second.