Gexwing simulates the effect of IES Lights in Cycles.
Answers.com desribes IES as:
IES stands for Illuminating Engineering Society. IES standard file format was created for the electronic transfer of photometric data over the web. It has been widely used by many lighting manufacturers and is one of the industry standards in photometric data distribution. An IES file is basically the measurement of distribution of light (intensity) stored in ASCII format. You can think of it as a digital profile of a real world light. In 3d software like 3ds max it can be used for creating lights with shapes and physically accurate form.
Gexwing writes:
Recently i started playing around with angle-dependent lights to imitage IES Lighting Profiles with Cycles. This trick works with Mesh-Lighting (Emission Shader), as well as Area Lights. I've found the Area Lights to behave better than Emission-Planes, mainly because you can independantly adjust the Size and Strength without influencing each other.
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5 Comments
Nice. I've always had a soft spot for IES.
It's funny to see it asked for in Cycles, and the Devs basically say, 'No, we're not going that direction', but yet provide us enough tools where it can be shaped to something they didn't really design it for.
Blender has always been like that. One of my best experiences was in the *very* early days when we didn't have halo spotlights. Of course you could fake them with a lot of object extrusion and transparent/glowing materials. It was very satisfying to do. And even more so when a few months later this feature was actually added :)
I guess when you think about it, it's like a lot of tools. (ie. power drills powering bicycles).
IES lights could be used in anything, I don't see why they are considered excluded to architecture use only.
All it does is describe how the light comes out of the fixture/globe setup... it's not as if only lighting engineers use them to accurately design lighting in a museum.
It's about making attractive, interesting and functional lighting, there are no limits to where that is needed.
If nothing was changed since I tried this method - it gives a lot of fireflies. Because of Area Lamp.