A highprecision, wide-field, stellar photometer, designed to perform continuous long-term observations of star systems will be onboard the spacecraft.
From photometer measurements of these three luminances a calibration table was calculated and included in the computer program that collected the data.
Light calibrations were made at the plane of the retina with a photodiode photometer.
I am told that it is possible to have a photometer which measures the luminous intensity of rear lights.
Reflected light was measured using a pyrometer lamp as a photometer.
The photometer has a soft focus to provide excellent photometry, rather than sharp images.
Apart from this post, his main body of work concerned the photometry of stars and the investigation of variable stars with a new photometer.
O and two fast photometers are used to correct star scintillation perturbations and to determine high vertical resolution temperature profiles.