L22 / photometry guide

Point and imaging luminance measurement

Choosing between a spot meter and a camera depends on object geometry, required spatial resolution and the analysis objective.

L22 educational guide · 2 min read

Spot measurement

A spot meter records average luminance within a defined field of view. It is useful for a well-defined uniform area or when a procedure requires a specific measurement field.

Imaging measurement

A calibrated luminance camera assigns luminance values to image pixels. One exposure produces a distribution map. The L22 camera is intended for LED displays, architectural illumination and road lighting.

How to choose

Consider detail size and contrast, field of view, distance, luminance range and required uncertainty. Imaging data does not remove the need to control focus, exposure, stray light and calibration.

FAQ

Frequently asked questions

Does an ordinary camera measure luminance?

Not automatically. A suitable spectral response, measurement model and calibration are required.

When is a luminance camera useful?

When spatial distribution, uniformity or simultaneous evaluation of many areas matters.