Red-Eye Special

[Godfrey]

I was browsing through some photos the other day, when I realized I was missing something from my attempts to make realistic eyes in A:M -- the annoying red pupil effect you get when the light source is lined up almost directly with the camera lens.

 

A lot of effort goes into reducing red-eye in the real world (from Sharpie markers to strobing flashes to software), but just like lens flares, it's an artifact that doesn't occur in CG unless you deliberately make it happen.

 

So here's a little test animation of what I came up with: EyeballTest.mpg (208 KB).

 

The basic technique's pretty easy; just a partial sphere inside the eyeball with a black surface and a large orange-red specular highlight. However, to get it to look right, I had to make the "retina" a separate model, set to not receive shadows, and constrained to the eyeball bone within the choreography.

[Rodney]

That's some amazing work you've done there Jeff.

Simple in concept (as you've explained) but awesomely implemented.

 

The dialation of the pupil makes that really work as well!

-Rodney

[ZachBG]

However, to get it to look right, I had to make the "retina" a separate model, set to not receive shadows, and constrained to the eyeball bone within the choreography.

What were other techniques you tried, and why didn't they work?

[heyvern]

Holy cow, you did that on purpose?

 

I thought it was an acident...

 

Still funny though.

 

p.s. No, getting contact lenses with little black dots will not prevent red eye.

 

Vernon "Ouch! Use the marker on the photo!" Zehr

[Godfrey]

What were other techniques you tried, and why didn't they work?

I tried making the retina part of the eyeball itself, within the main model. That worked fine as long as shadows were off; but when they were turned on, the retina remained black (not enough light getting through the pupil, and I suspect the IOR of the cornea may have been mucking things up as well).

[ZachBG]

Hmmm.... guess I'm not clear on the layout. Can you post a wireframe and maybe an exploded view?

 

(Exploded eyes, yum! Call Quentin Tarantino.)

[Godfrey]

Hmmm.... guess I'm not clear on the layout.  Can you post a wireframe and maybe an exploded view?

Sure thing. Here's the exploded view:

 

 

And this is how it all fits together:

 

 

 

(Exploded eyes, yum!  Call Quentin Tarantino.)

Yeah. My wife refused to be in the computer room when I was painting the eye decal. She'll be thrilled when I tell her I have to do another one (don't want to end up with two identical eyes, like Gollum in LoTR)...

[ZachBG]

Oh, now I see (pun intended)... we're looking at the inside of the retina sphere. Cool! Guess I need to brush up on the ol' anatomy.

[scrawntor]

Very cool, you sure don't see that kind of a detail in CG movies. good thinking and nice work.