The room I used as reference for the light tube simulation (see post from Summer 2011) staged additonal lighting experiments. Tatiana Kartashova examined how observers adjusted the illumination on a probe in order to fit it visually in three diversely lit scenes.

The video illustrates the experimental setup for the paper “The global structure of the visual light field and its relation to the physical light field”

In this experiment, the diffuseness was defined as the ratio of collimated and ambient luminances, ranging from fully collimated light (e.g., spotlight) to fully diffuse or Ganzfeld illumination (e.g. as in mist or a snowy field on a cloudy day).

The open access paper from the Journal of Vision.

Read more from the source: youtube, Published by: Tatiana Kartashova

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Overview of light sources described.
Links to additional information and resources about IES TM-30
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