an old post from my FA gallery

the eyes i use in my models are based on the pixar eye tutorial at https://www.youtube.com/watch?v=gfEyhPXsOCM

there are a few things you need to be careful of:

1. the tutorial works in both cycles and eevee but you'll need to enable a few settings in eevee to get them to work (they're mentioned towards the end of the video)
2. cycles VIEWPORT render sometimes doesn't update the eye direction from the armature, but it will look fine in final render. you can select the eyes or armature and tab in/out of edit mode while in viewport render to force it to update. i spent hours chasing this down only to find out that it was a bug and not something wrong with the shader nodes :)

(editor update: i think #2 was a bug that has since been fixed)