View Full Version : Skin Shader study part 1
05 May 2004, 07:52 PM
Here is a repost of my skin shader approach for C4D 8.5. It isn't exactly the same one as the older one, since I didn't have a backup copy.
1. Choosing the right shading model. C4D has three shading models to choose from, Phong, Blinn and Oren Nayer. I was looking for the right model that would be ideal for youthful, moist skin, and with Oren Nayer I was able to get qualities of waxiness, and fluidity to the material. In CG a common problem exist with shading models interms of how they react to light. Mainly that it doesn't mimic how lights in the real world actually wrap around a surface and to effectively depict skin we need lights that will wrap around our models, giving it a real world feel, and without proper ligthing behaviour our effort wouldn't be as convincing. To fake a wrap around look for lighting we would need to lower the diffuse falloff percentage. I have set mine to -30%, but be aware that lower to far will grey out your color. I also adjusted the roughness to get a softer look.
2. To start creating our skin shader. I create a layer in the luminance channel. The first layer I create is a noise shader with the following settings. The idea was to create the underlining vein material under the skin.
3. I add in another noise shader with the following settings to create another dermal skin material, almost like goose bumps.
05 May 2004, 08:07 PM
4. Here I add in a falloff effect with the following settings. the idea here was to show redness of the skin from blood/fluids in the body. The falloff effect is controlled in XYZ axis. I have mine set to 0 in X, 1 in Y and 1 in Z, so the falloff is in front and up. It is more than possible to have multiple falloff effects with varying colors to depict other skin quality and depth as well as being controlled by other objects, lights, shader, camera and on on. A very usefull shader.
5. Here I add in another useful shader, a fresnel with the following settings. The idea here was to give your model warmth and color from sun exposure and some more depth as well as a bit of peach fuzz on the silhouettes.
6. Here I add in my texture map painted in BP R2 in about 15 min. Because of the effectiveness of the skin shader I painted just simple colors and I didn't have to try to make convincing skin textures on my own.
7. Optional. If you have access to SSS or other such effects it isn't a bad idea to incorporate it into your material. I used the SSS that comes with Advance Renderer in the 8.5 version. I blended it with "Add" to the rest of my skin shader in the luminance channel.
Note: Leave it on or check it on the use Bump option for frensel and falloff, as it will do a nice job of breaking up the material and gives a less than smooth look which is what real skin tend to look like. For lighting I have my key light at 60% brightness in a studio lighting setup and with soft shadows at 1250x1250, sample radius at 6 and bias (abs) also at 6.
05 May 2004, 12:49 PM
thanks for reposting that. it's a great looking shader. Can I ask what are your settings in the bump, specular and specualr color channels?
05 May 2004, 02:17 PM
thanks for posting this again tony.
btw are you trying something to do with bssrdf?
slightly OT tuts...but worth a read
05 May 2004, 05:30 AM
Thanks for sharing this tasty shader idea:thumbsup: I will have to sit down and play around with some of these settings...some great ideas there. The new layer is just so damn indispensible for this stuff! I am also curious to know the settings in the other channels if they are relevent....
05 May 2004, 11:41 AM
Thanks tjnyc, this is a great tutorial.
Now that I have 8.5 I can use it.
Here is the link of your first version, in French, mad by Aurety for the FrenchCinema 4D.
If you need I can translate it back to english.
05 May 2004, 01:25 PM
I asked this in the original thread, and I got emails informing me that there were responses (though I'm not sure they were responses to my query), but I never saw them before the thread died. In any event, I'll ask my reask my [very n00bish] question.
How exactly do you get layers in a shader channel? For the life of me, I can't figure out how to do this. :shrug:
I know Maxon advertizes "Layer Shaders" as a new feature in 8.5, so I presume it's not a BodyPaint-only feature.
Thanks in advance,
05 May 2004, 01:29 PM
...Found it:banghead: :blush:
05 May 2004, 01:44 PM
I posted a question that should have showed up before my "Er, nevermind" post, but it was the last "new user moderated" post, so it looks like they'll show up out of order.
Anyway, I found the answer to my own question (about shader layers), so feel free to ignore me. :blush:
07 July 2004, 06:35 AM
Reviving an old post!
Some of my findings on skin shaders and the method described here...
1) It is worth plugin the bump map into the spec colour. And colourise it blue first.
2) The shader system above plugs all the effects into the luminance channel. Good results can also be obtained by mixing them in the colour channel. Although if you do this, add a hint of red in the luminance channel.
3) Adding SSS - I've yet to be able to get any reasonable results using the SSS shader - but still experimenting.
4) I'd already been using the fresnel channel - helps a lot - but never tried the gradient map. Works a treat - dunno why - but it just does!
Anyway, thanks for the above post - very useful imformation.
01 January 2005, 03:06 AM
Great tutorial! Many thanks for sharing!!
/\>Scott M C4D</\
01 January 2005, 05:50 AM
What i really want to know is why has she got a bald head.
Makes me want to upgrade from 8.2.
01 January 2005, 10:29 AM
Because beauty is only skin deep. Underneath there is only a mes(s/h)...
04 April 2005, 02:43 PM
fantastic tut. helped me alot getting started with my skin shaders!
04 April 2005, 03:21 PM
You can also setup just one direct light and ambient-occulsion to match your environment and real-world lighting. Use HDRI for IBL in C4D for the environment lighting, blur and offset as you need to. Use GI with a white material matte for the occulsion part and composite to your beauty-pass, or a texture pass, and a direct lighting pass.
11 November 2005, 06:41 PM
can you the material with sources of light without object for the download offer?
05 May 2006, 06:07 PM
Would have found this tut quite usefull if the images had shown up :(
05 May 2006, 06:08 AM
This thread is two years old. It's not unlikely that linked images are not working anymore.
05 May 2006, 06:08 AM
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