The page is the light
The eye has one key light, and it is the site itself. Each era's real home page is captured and stood in front of the eye at true size, where it lights the face and shows in the cornea.
The problem
A rendered eye needs a light, and any light an artist invents is a studio light. It says "this is a 3D render". It also has nothing to do with the era.
The move
Use the screen. Every era of this site has a real home page. A script opens each one, captures it at 768 px wide, and saves it. In the scene that picture becomes a rectangle with a real size and a real distance: a 1970 tube is 244 by 183 mm and sits 600 mm away. A phone is small and close.
That one rectangle does three jobs:
- it is the key light on skin, white and iris;
- its mirror image is the only bright thing in the cornea;
- its average brightness sets the size of the pupil.
Change the home page, run the capture, and the eye changes with it.
What it rules out
Recolouring the eye to suit an era. An early 1970 tinted the iris green and it read as green fur. Colour arrives as light from the page, or as the medium the frame is drawn in. Pigment stays put.