2023-02-15 (Commercial) Course: Shader Magic in Blender
Joakim Tornhill doesn’t care about IES lights. 
Me, I had never used one.
#17 IES texture.
Joakim’s introduction was very basic, even more basic than the others, since he doesn’t really consider it part of what the course covers. Makes sense.
So an IES texture isn’t really a texture. The fine manual says “IES files store the directional intensity distribution of light sources”. This makes it possible to finely tune how one wants one’s lights emission to look. I used the free IES files from Pixar to experiment. The course has one in its resource image zip, but I didn’t remember that existed until afterwards.
So much for the course, as I said, very basic. But y’all know me probably by now, and that there is no rabbit hole I won’t gleefully dive in to let myself be distracted from any goals I might have originally had. I went to find out more about IES lights at digital.ARCH. The article has another link to free files as well.
Shader setup after reading that article, simple:
I learned that publicly available lights aren’t standardized, and can increase render times considerably (I noticed). And that makes an already fiddly process (moving and angling the lights to get what one wants) even more prone to issues. Look at the huge difference in intensity between this standard Blender spot on the left versus the Pixar “bollard” on the right. Same colour, same power, same radius, same size.
So of course I want to learn how to make my own IES lights because I was reminded of that isometric bedroom scene; would have been interesting to give the nightstand lights their own IES profile. One can do so with an external tool, such as: CNDL (Windows only, but at least opensource). Or one can do it in Blender, and if one uses mesh lights, adjustments become a lot easier (Chocofur article). Chocofur also has some free IES lights. The shader setup is more complicated, and I’ve put off doing this until I need it.
Mesh lights? Yeah, I had no idea. Well, I’ve used mesh lights (as the name says, a mesh that emits light) but I didn’t know there was a special term for them.
:dusts self off from flotsam and jetsam acquired in the rabbit hole:
Music: Tones and I (Australian singer-songwriter, indie pop)