i'm new to rendering and i'm following on the introduction course to rendering in mental ray.
the instructor said that you can use Final Gathering to light your scene, even if you don't have any lights.. like by just positioning a polygon plane with a very bright shader on top of your geometry.
now, it's not the same with Global Illumination right? because this GI feature is based on lights. (the lights are "sending" photons which gathers color information from the environment and then "spills" it over the scene, while FG places dots all over the scene, that are sending rays to collect hue/saturation/etc.. information from the environement, which determines how each "dot" in the scene will be shaded?).
just wanted to know if i'm right about this or not, to be clear..
Hi EladTzemach! You are correct that FG rays do not require a light in your scene whereas GI photons are cast from a light. You can see how photons and FG rays are cast differently by turning on the Map Visualizer. Here's a quick video to show how you can do that to show the differences. Hope it helps!
Here's a link to the mental ray Workflows in Maya: Final Gather course and mental ray Workflows in Maya: Global Illumination that was referenced in the video.