How to hide mesh based lights on Blender Cycles?
The use of mesh-based light in Blender Cycles is one of the most important elements to setup a good light for architecture. But, there is a small inconvenience with those types of lights. They are big planes or objects that emit light, which will result on them showing up on the rendering. If you don`t want to try to hide those objects by placing them off scene, or even changing the camera to avoid framing the light sources, this quick tip from an artist called DDDGamer will help you to hide all mesh based lights at render.
The secret? Use some nodes to hide them only at the render.