Sub surface scattering again...

[TheBadger]

Here is just for fun the head in stereo for cross eyed viewers. Are there any?

I can't believe that really works! HA HA HA It really hurts to do it too, but its worth it cause its so funny  Oh man you are funny.

[Dune]

You are taking this into unbelievable heights, Hannes, absolutely stunning. The stereo effect is super (I'll get rid of my headache later, after a drink or so). I wonder if you could manage a longer beard with this method; the main problem then probably is to angle them the right way, but a pf for the hairs to sit on, without linking it to the head itself would be an option to have them at different angles to start with. With a lot of clever masking that might work (sevaral angles, several pf's, several masks), but is it worth the work?

[Matt]

Usually one would think 50% grey will remain 50% gray after an inversion,
but as can be seen in TG it is not.

Matt can you please tell us what TG does here?

Your 50% grey looks like it might be 50% grey in sRGB colour space, but it's not 50% in linear colour space. If you load an 8-bit (or 24-bit RGB) image into the Default Shader it assumes that the image is in the sRGB colour space and applies a gamma correction of 1/2.2 to approximately convert it to linear colour space. Any invert options you enable in the shader happen after this conversion. Inverting your 8-bit image in Photoshop will give very different results.

http://udn.epicgames.com/Three/rsrc/Three/TexturingGuidelines/gamma_vs_Linear.jpg



Matt

[bobbystahr]

Great info Matt, often wondered why that happened. Thanks.

[j meyer]

Thanks Matt,valuable info!
That should enable us to get it right.

[Hannes]

Tried to use the SSS on something else: beer froth (or beer foam? What's the correct term?)
Encountered a problem when there is a solid body with a glass (or water-) shader inside of another solid object with another glass shader. I tried all combinations of doublesided (material and object) on or off, shadows on or off. No matter what I did, I got Guinness (see attached image - first three renderings).
I finally found out that I had to uncheck "visible to other rays" inside the glass shader of the glass (Fourth render).
For this image I had to use quite high settings again to avoid artifacts. GI 5/5, Render detail 1.

[Hannes]

...even more delicious, when the glass was in the freezer for a while.

[Kadri]

That looks cold and tasty. Prost

[Hannes]

Zum Wohl!!
Improved the foam.

[Kadri]

I know what i will drink tonight

[j meyer]

According to the "Reinheitsgebot" I assume?

Maybe a thin localized cloud layer to make the froth
fuzzier could work.

Why do I think of Sauerkraut and Schweinshaxn all
of a sudden?

[Dune]

You amaze me again and again, Hannes. And make me thirsty 
Are the bubbles procedural?

[Hannes]

Thanks guys!
Ulco, do you mean the bubbles in the foam? No, it's an edited image map I used for displacement and another version as an additional diffuse map, to get the bubbles convex, but a little darker inside.

[WAS]

Usually one would think 50% grey will remain 50% gray after an inversion,
but as can be seen in TG it is not.

Matt can you please tell us what TG does here?

Your 50% grey looks like it might be 50% grey in sRGB colour space, but it's not 50% in linear colour space. If you load an 8-bit (or 24-bit RGB) image into the Default Shader it assumes that the image is in the sRGB colour space and applies a gamma correction of 1/2.2 to approximately convert it to linear colour space. Any invert options you enable in the shader happen after this conversion. Inverting your 8-bit image in Photoshop will give very different results.

http://udn.epicgames.com/Three/rsrc/Three/TexturingGuidelines/gamma_vs_Linear.jpg



Matt

Why in all that is holy would Terragen assume anything is in a arcane format like SRGB for CRT monitors? lol It should only use Native RGB/CMYK for plasma/lcd now. You'd think CMYK would work best considering the whole gamut is a natural tone set from the 'real world' and would probably work best for shading such a 'real world' image.

Also sRGB incorperates both linear, and non-linear gamma corrections leaving you with a adjustment o 2.3 at the end, not 2.2. Could explain a lot of the anomalies in TG with it.

[otakar]

Bier vom Fass at Hannes' house, everybody!  Looks great with the frosting, though I detest ice cold beer. Oh and the foam is called beer head.