I'm seeing some differences with IES lights in V-Ray. It seems the light color is treated differently than other lights.
Darker colors should reduce the brightness of the light. I'm attaching a sample scene. It also has an area light and you can see this matches modo, while the IES light doesnt
20170107_ies_test.zip
Darker colors should reduce the brightness of the light. I'm attaching a sample scene. It also has an area light and you can see this matches modo, while the IES light doesnt
20170107_ies_test.zip