Scene Size Influence
This page describes how the size of a scene can impact the sensor's perception of the scene's illumination.
The distance between the sensor plan and the emitting scene impacts the sensor's perception of the scene illumination.
If the sensor plan is placed at a certain distance from the emitting scene, the sensor defines a cone under which the observer sees an area through the pixel.
The luminance is then integrated over this observed area.
Therefore, there are at least two cases to consider if you want to study the influence of the emitting scene dimensions and the integration angle of the sensor on the luminance value.
| Visible surface of the scene is smaller than the observed area | Visible surface of the scene is bigger than the observed area | |
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_Sensor_Integration_Angle_Scene_Size_02.png) |
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When the visible surface of the scene is smaller than the area observed through the pixel aperture, the luminance is integrated both over the visible scene and the unilluminated area. The average luminance value is then lower than the average luminance value of the scene because the average is made on the illuminated and unilluminated areas. |
When the visible surface of the scene is bigger than the area observed through the pixel aperture, the luminance is integrated over the visible surface of the scene. We observe the luminance variation as a function of the integration angle and the visible surface of the scene. |
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