An important thing to keep in mind is that light intensity can vary significantly within a model. Just like in real-life, if daylight is coming through a window and you look toward it, your eyes compensate for it and adjust. If there are lights on within the room, they can become add less to the overall room brightness if the light coming through the window is too bright. This complex, sometimes subtle, change is taken into account by adjusting the Exposure like an automatic camera. These adjustments take into account over- and under-exposure due to contrasting light intensities.

These two images have the same lighting intensities in the model, but the sunlight coming into the room can be seen hitting the floor crisply only in the first rendering. This is because of the exposure adjustment, which compensates for the brighter spots by “stopping down” the camera lens.

Download PDF for AccuRender Tutorial: Adjusting Exposure