Apogee Instruments SQ-514 Owner's Manual - Page 8
Browse online or download pdf Owner's Manual for Accessories Apogee Instruments SQ-514. Apogee Instruments SQ-514 20 pages. Quantum sensor
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Cosine Response
Directional (cosine) response is defined as the measurement
error at a specific angle of radiation incidence. Error for
Apogee SQ-500 series quantum sensors is approximately ± 2
% and ± 5 % at solar zenith angles of 45° and 75°,
respectively.
Mean directional (cosine) response
of seven apogee SQ-500 series
quantum sensors. Directional
response measurements were made
on the rooftop of the Apogee
building in Logan, Utah. Directional
response was calculated as the
relative difference of SQ-500
quantum sensors from the mean of
replicate reference quantum sensors
(LI-COR models LI-190 and LI-190R,
Kipp & Zonen model PQS 1). Data
were also collected in the laboratory
using a reference lamp and
positioning the sensor at varying
angles.