Strategies for reflections and lighting eyes

Eyes should be rotated out a little, here we used 7 degrees

Make a transparent covering over the eye with the front pole pulled to a soft peak

Use a ref to get the eye right

Before you get into mental ray and all that, get the basic reflections in the eyes right with a standard directional light and an output map set real high.

We have one keylight, a camera, and a reflecting card.

Make sure your card is rotated towards the model ...alternatively, use a low poly sphere or a box. This shows the back of the plane.

Note – you can also keep a large plane behind the light and use a very long distance from light to subject. Narrow the falloff.

The map settings to handle the reflections – note there is no fresnel as well as no specular/glossiness. We will have genuine reflections completely over the globe. Set the reflect to about 10 so we can still see through the covering.

You can see the need to make reflection only 10% if you place a gray sphere inside the outer covering ... if the ray trace is set to 100% reflect, the eyeballs will become like a mirror and you will not see the pupils, etc.

Add a bump to your ray-trace for a much more interesting look:

Vary the settings to tweak the reflection ...

The card is 2-sided to protect yourself from facing it the wrong way, and so you can see it.. Later go back and correct that to avoid longer rendering than necessary.

Self illumination is 100. The diffuse map is output.

Here is a render of our rough working setup with and without the bump.

Aiming up the card ... make sure it is facing the eye ... our output rgb level here is set to 15.

With some noise ...

To avoid a bulging look as the eye refracts into the transparent eye covering, turn off raytrace reflections on the covering [outer globe]

avoid this:  this is better:

This next version is for the default scanline renderer. It uses a similar approach to the previous, but with hdri instead of a reflection card.

Turn off the bump and place an hdri in the environment slot. You will have to download one off the net.

Set the hdri image as a texture

Apply and set a UVW modifer as a plane

Increase the output of the hdri

With mental ray on:

This last method uses mental ray.

Create a mental ray material:

Put a Dielectric Material [3ds max] in the surface slot:

This shows putting in the hdri into the environment slot

Position and scale up the UVW gizmo as desired.

Set the eye [except for the pupil] to self illumination of 100%

Turn on final gather and GI.

Scale up and move to isolate areas you like

You can add a SSS physics material to the inner sphere of the eye along with a diffuse map; the one on the left has sss.

You will need GI on for sss. Leave FG off for now.

The settings of the ss we will go into later.

Set the diffuse map of the eye to 100% illuminate and combined with the transparent reflective cover. The eye on our left has the sss on the inner sphere which creates a problematic doubling effect.

You can upgrade your cards to mental ray with output and photons to generate more gi.

The inner eye with the color is the rgb image – make sure to add your light as shown.

The outer globe for reflection is

The 2 globes together are shown below. We will go on to adjust the settings for the sss later on.

An extremely effective method is to situate a card directly behind the key light source, as it throws very refined colors into the eye. This becomes data we can use when we adjust the sss.

[Note – some prefer to situate the cards behind the camera.]

You can further control how the card impacts the eye by addressing the output for both the surface and photon shaders. The distance of the card to the eye, the size of the card the bump, ... all these factors are critical.

Here is the “amped”  photon:

This final version shows an hdri reflection.

The inner globe does have sss.

Experiment with falloff on or off in reflect slot.

Experiment with increasing output of the hdri. This one is set to 10 rgb level.

Bump/noise is as above settings.

Hand placed reflection cards plus the hdri

If the sss on the inner globe gets to be a headache you can use a regular diffuse map with 100% illumination or even some output.