How do I make fake Eye Reflections work?

dalibuwaitur

How do I use fake eye reflections? 

When I add one to the model, it shows up in the preview, but not in iray renders.  How do I fix that?

I'm talking about .duf files that look like eye reflections but are static and do not actually reflect light.  I think they're called eye reflection maps. 

Lighting = default iray lighting only.  Adding more lights had no effect.

SpottedKitty

I think most of these "fake" reflections are actually for rendering in 3Delight, not Iray. Reflection maps can't really be used in Iray, it generate real reflections from whatever scene you have surrounding your figure.

When you say "default Iray lighting", are you doing anything at all in the Render Settings? I get very good reflections if I rotate the default Environment light so it shines into the figure's eyes (the default setting is for bright sunlight coming from stage left).

fred9803

As SK points out Iray reflections reflect the environment, and without a surrounding environment they will reflect nothing, apart from a light source comming from a specific angle in realation to the camera.

dalibuwaitur

I found a round-a-bout solution.  I applied a geometry shell to the G2F, then in Parameters turned off all the surfaces except for the eye reflections.  I then selected the Surfaces tab and could then apply the fake reflection to that.

 

nonesuch00

What I did was crank up to Top Coat to 100% on the cornea and sclera, set the Top Coat color to .8 .8 .8 or .9 .9 .9 if you like. The Top Coat Roughness I set to 10 or 20 or 30%. Eyes now look much rounder now although sometimes I get odd shaped reflections but it's better than the old flat painted on look they had.

I actually did similar for all skin surfaces except I set Top Coat color to .7 .7 .7 and Top Coat Roughness to 50% for that thin sheen of oil. I deleted the spectral maps but as the oily locations on the DAZ ones are accurate what I really needed to do was make the spectral maps more effective. I tried dialing up the Top Coat Weight to 1.0 but that still didn't make them effective enough. What I really need to do probably is take DAZ Studio's original greyscale maps for spectral and reduce the range of greys to 4, 8, or (probably too many) 16 and then weight it so the oiliest area of the cheeks and nose is weight as if it were 0 IR would it be 255?

Also the DAZ Genesis 3 translucency settings have scatter and transmit which was causing colors to be transmitted that are much darker than what the lighting in the scene would indicate for I changed those to scatter.

I would have to have introduced external lighting to HDRI scenes to get results like what people expect (indeed that what many other people do do)

I think the DAZ spectral maps are probably fine as issued if you are doing some gargantuan X by Y render but when scale is reduced to what I render at, typically only about 1100x800 (size of my viewport in Maximized DAZ Studio on a FHD monitor) the detail is too much in depth and that depth need's to be scaled down to be effective at smaller render resolutions. Eg fictionally I render at 2000x2000 native DAZ Studio resolution and spectral maps have 64 levels of grey originally but I reduce that size to 500x500 so the number of grey scales in the spectrals should be reduced by a similar amount, to 16 levels of grey and not toward the middle ranges but the top ranges. This means spectrals and such maps would need to be regenerated from a base reference on the fly for differing render resolutions. Maybe DAZ Studio does this already? I don't get that impression from my results. Also, although I gave an example relationship between the HxW scale of a render and the depth of a greyscale map as constant maybe they probably aren't and DAZ would need to find an appropriate relationship between HxW scale and the depth of these greyscale maps that looks more typical in the average lighting of good HDRIs.