Dr Julian's Texturing Tutorial. Page 5

More spots. These where painted on top of the spots on my spot bump map layer if you can remember it
On this layer I painted some soft blue tones then multiplied you should be able to see the effect they achieve.
Now a vein layer , your hardly even see these if at all, but it gives the impression of something under the skin. you could pick out one or two that looked the best and copy then on to another layer and make them stronger.
Then use the same vein layer on the bump map using colour dodge to make a slight bump where the vein is.
Now for a few small random veins here and there.
I've added some scaring, the characters face is actually meant to be covered in scars but i'll see how it looks before I add more.
Now you can use some of the bump details on the colour to darken where the wrinkles are, sometimes it can look better if you paint over them with a more reddish colour where the wrinkles are (like the scars) but that takes time, but can look a little better.
Here's the sort of finished colour map but you can't really say finished, things always need tweaking.
Now I can't provide this full photoshop file because its 400mb big. So i've had to reduce it in size and cut it down its now 684 by 1031 18mb in size.
The picture left is what's left
Now before showing some of the other textures I use, I will show you one of my skin shaders and try and explain the connections, below is a map of the connection for my maya 4.0 shader.
I have colour coded various parts, it's basically made up of five different layers.
I'll start with the Bottom layer which is circled in RED, this layer does not really have that much effect.
But i'll explain what textures are assigned here. Marked A is a translucence map click here to see it in more detail. This layer it just to trying to achieve some sub surface scattering effect underneath the main skin layer.
Marked B is a Diffuse map, I find the maya default renderer tends to fade the textures no matter how deep you make them this map is just trying to keep all the areas like the spots and marks as deep and possible trying to keep as much variation in the skin contrasting light areas with nice dark spots.
Right Marked C is a ramp colour node based on the ideas of Dr Steven Stahlberg's skin shader Link, this is plugged in the the ambient map trying to give a reddish glow coming thought the skin, but you'll hardly notice it.
Marked D take no real notice of this one it's just a few different skin tones taken originally from a good shader by Dr Matt Wood link.
The layer that goes above the bottom layer is circled in YELLOW sorry the hyper shade map is laid out a bit awkward i should of arranged them in the right order but did not really have enough time.
Marked A This is the maya skin shader which you can get of the maya web site Link its very good for bringing out the rice skin tones, but does take some tweaking to get the right look.
Marked B is the colour map of course.
Marked C it's the bump map.
Marked D this is a reflectivity map this brings out some of the nine shiny tones you might want here and there.
Now it may be a bit hard to find but circled in PINK is a transparency map this is used to blend with the bottom layer some areas i want to keep dark as possible other areas i'm happy for the reddish underneath to blend though.
Next up circled in GREEN is a ramp based shade trying to fake some translucence in to skin once, again taken from Dr Stahlberg's skin shader Link reading his great tut will tell you about it.
Circled in BLUE is a blinn spec layer using a part of Dr Emmanuel Campins back light shader Link giving nice side glancing highlights
Marked A is just the spec map.
Circled in WHITE is the top layer this is just a another spec layer, a phong this time I try to get some nice wet highlights on this layer the skin looks little to dry other wise.
Marked A is a spec map.
Marked B is another translucence map bringing out some more reddish tones around the ears.
And that's it for the shader description.
For the final part of this tut I will just go though the other maps and how I made them.
Sorry but this tutorial does not include any lighting or rendering tips, that will come in a future tut.
First i'll have a look at the spec map.
This map just controls the shininess of a shader, I used part if my GI light baked texture Map to help darken a few areas.
Areas like the nose and lips usually have more shine or glossiness to them, areas like the bottom eye lid aswell. Have look at someone and see how shiny and reflective the bottom eyelid can be.
If I want to tweak this map or add colour to it, I usually do that in maya, to achieve a really wet highlight, I might alter the level making darks dark and light areas really bright.