This tool shows a sun diagram for a specific location at any point in time.

Manufacturers provide IES files that capture a luminaire’s photometric data, so Revit can generate a photometric web and render the light source accurately.

A free online IES editor that can open, edit, and print IES files.

An article posted by RD Studio, a company that sells high-quality Revit components and families, that links working Revit light fixture families and lighting manufacturers websites.