Assessment of measurement uncertainties for imaging luminance measurements

This paper presents an approach to assess the measurement uncertainty of luminance measurements obtained by imaging luminance measurement devices (ILMDs). A common strategy for users doing measurements in photometry is to characterise and correct for residual errors, that in this domain are often significant. To apply this strategy to measurements with ILMDs leads to issues because the user only has limited knowledge on the device internals and the effort for such characterisations would exceed the capabilities of most users. To illustrate this, the complexity of the devices' internal operation is shown, and tasks of the manufacturer to build and adjust an ILMD based on a camera system are outlined. From this we concluded, that for most users, the best approach is to assume that all significant effects have been corrected for by the manufacturer, and only the remaining uncertainties need to be estimated. An example is given for this estimation and for the handling of correlations between measurements.