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# Revision history [back]

### ambient bounces 0 with

I created an HDR image in Radiance of a room with sunlight coming through a window. I set -ab 0, but the walls seem to be reflecting light. With this setting, shouldn't the window be the only "source" of light? What's more, even when the simulated sunlight has barely "risen", the walls seem to be equally luminous. Are these walls somehow becoming sources? Any insights?

9 am: 7 am:

### ambient bounces 0 with

I created an HDR image in Radiance of a room with sunlight coming through a window. I set -ab 0, but the walls seem to be reflecting light. With this setting, shouldn't the window be the only "source" of light? What's more, even when the simulated sunlight has barely "risen", the walls seem to be equally luminous. Are these walls somehow becoming sources? Any insights?

9 am:

7 am:

### ambient bounces 0 with

I created an HDR image in Radiance of a room with sunlight coming through a window. I set -ab 0, but the walls seem to be reflecting light. With this setting, shouldn't the window be the only "source" of light? What's more, even when the simulated sunlight has barely "risen", the walls seem to be equally luminous. Are these walls somehow becoming sources? Any insights?

9 am:

7 am:

### ambient bounces 0 withLuminous walls with -ab 0

I created an HDR image in Radiance of a room with sunlight coming through a window. I set -ab 0, but the walls seem to be reflecting light. With this setting, shouldn't the window be the only "source" of light? What's more, even when the simulated sunlight has barely "risen", the walls seem to be equally luminous. Are these walls somehow becoming sources? Any insights?

9 am:

7 am: