Luminous intensity is measured in candelas (cd) and can be measured using a photometer, which is a device that measures the intensity of light as perceived by the human eye.
Photometers can measure luminous intensity directly in candelas, or they can measure illuminance in lux and distance in meters to calculate luminous intensity using the formula: Luminous Intensity = Illuminance x Distance².
Radiant intensity is a different physical quantity than luminous intensity, and they cannot be measured using the same system. Radiant intensity is measured in watts per steradian (W/sr), while luminous intensity is measured in candelas (cd).
Therefore, it is not possible to measure luminous intensity using an analogue system designed to measure radiant intensity.