Hello, welcome to the second part of the Greek Sculpture tutorial. I hope you enjoyed the first part.
Now we are going to learn a little more about the Greek tradition, particularly taking into consideration our subject: the render. How can we render this statue? How did the Greeks and the Greco-Romans finish their pieces? I'll try to answer some questions about this and provide a simple tutorial about how to achieve a good quality render.
Analyzing The Sculptures
When studying the Greek traditions we can see that their sculptures were predominantly finished in marble. Also you will find that a lot of the sculptures were actually painted originally and, at the very least, the hair and the eyes were painted. With this in mind my intention was to make a marble statue with some painting in the hair and maybe in the eyes. I didn't want to make the sculpture look like it is totally finished and wanted it to look as if it has become worn over time. So it was clear that I would be adding some dirt and some faded paint.
It was important at this point to also think about the light. Of course the Greeks didn't have to think about lighting as their sculptures were generally used in external environments. However we don't want to deal with the lighting in a careless way, but instead concentrate on intensifying the tension and mood of the scene.
Preparing The Scene
Once you know a little about the history it's time to start our render. The first thing we need to do is create some lighting sets to find the best position and intensity for the lighting. The render is going to be done in V-Ray, so to start we need to export the model into 3ds Max. To do this, select the model and the division that has all the information that we need. You don't need the high resolution model at this point as this is just to test the lighting.
Now, in the ZPlug tab, open the Decimation Masters plug-in (if your ZBrush doesn't have it, download it from the Pixologic site). This plugin will maintain all the model information, but will reduce your poly count a lot (Fig.01).
When you open this plugin you can see the option called "% of Decimation 20". This option gives us the option to choose what percentage of the actual polygons we want when the program finishes its calculations. So let's start with 20% of my polygons, which means if the model has 1 million polygons, in the final version it will be 200,000 polygons without losing any detail information. When it's done we need to pre-process all the subtools. After the calculation is done we only need to use the Decimate All button and our model will be reduced. The next step is to click on Export All Subtools and save all the subtools as an OBJ file (Fig.02).
In 3ds Max it is better to work with a real scale. To do this open the Customize tab, and then click on Unit Setup and configure the scene as shown in Fig.03. Now our scene is configured to cm. The next thing to do is create our infinity background. I decided to do this to simulate studio photography. To start this we simply need to create a plane object in the Standard Primitive tab and set the scale of this object as in Fig.04.
Now to apply a curvature to this plane to make our studio background, open the modifiers list and pick the Bend modifier (Fig.05). Next adjust the Bend Axis to X, the Angle to -90, and turn on the Limit Effect to find a good value to make a smooth curvature. Once you have done this your background is done (Fig.06).
When this is done you can bring in the statue. To do this go to Import and select your OBJ. When you have done this adjust the scale of the statue to fit the background (Fig.07). In this case I used a simple box to work out a suitable scale for the model. I decided to make the statue a little bigger than a real person, a bit like a monument (Fig.08).
Once this is done we can test and find the best lighting for our scene. First we need to open the Render Setup then go to Assign Render and in the Production section pick V-Ray (Fig.09). Now we can adjust a few settings in V-Ray to make quick renders to test our lighting without needing to wait a long time to see the results.
By adjusting the settings to the way they are in Fig.10 we will have everything we need to run a test. The other thing we need to do is create a simple material and apply it to all the models. Open the Rendering Material Editor tab and create a V-Ray material with a light gray diffuse color (Fig.11). After that is done put this material in the "Override mtl" slot in the Global Switches tab (Fig.12). Now we can create a V-Ray camera, configure it to 50mm and change some of the configurations like the aperture (f-number), Iso and shutter speed (Fig.13).
By clicking the C button we can see through our camera now. I like to turn on Safe Frame to see the exact proportion of my render in the viewport (Fig.14).
Now it's time to create some light. The lighting is responsible for the mood and tension in the scene and adds to the drama. From the beginning I was thinking about a dramatic light source coming from above, as if it was a light from the heavens. I decided to use the contrast between light and shadow to show how Adam is moving away from light, coming away from God.
I wanted to show that the important thing is not how much light you have in the scene, but the purpose of the light. So for this model I'll use only one light to show what a simple light put in the correct place can achieve.
Open the Lighting tab, choose V-Ray and give the light a green color. I chose green because I wanted to simulate a fluorescent lighting (Fig.15). After some tests I found a great position to create the mood I wanted (Fig.16).
After we have achieved the desired mood it's time to paint and texture the model. Like I said before, I tried to create a worn, dirty marble effect. So we need to come back to ZBrush to use Polypaint. First, pick a de-saturated and bright orange by going to the Color tab. This is going to paint the color onto the model (Fig.17).
Next turn on the Cavity brush by going to Brush > Auto Masking > Cavity Mask. This tool will simulate a dry-brush effect. With this tool we are going to paint the overall color of the model (Fig.18).
Now it's time to paint some imperfections and dirt into the model. To do so pick the Standard brush and choose the Drag Rect stroke option. For the alphas I searched the web for some images of dirt and worn paint and projected them onto the statue. Sometimes I do this with a low RGB value to create some overlays (Fig.19).
Using the Dam Standard brush (you can find it in the lightbox/brushes) add some little scratches to the model to create a naturally scratched look (Fig.20).
Now to finish the model we are going to apply some Surface Noise. The tool to do this is located in the Tool palette. By changing some of the parameters you can achieve the look of old rock. Once you are happy with the effect all you need to do is click Apply to Mesh (Fig.21). Then repeat this texturing process on all the subtools (Fig.22).
Now it's time to create our maps and send the model to 3ds Max. The first thing we need to do is to create a UV for our model. For this tutorial we'll create a simple UV using UV Master. This is a plugin for ZBrush that creates UVs easily and quickly.
Open the UV Master in the ZPlugin tab. Then click on Work On Clone; this will duplicate your model (Fig.23). Now with the copy of the model open click on Enable Control Painting and click on the Attract From Ambient Occl button. This will calculate the UV from the Ambient Occlusion. After that select the Protect button and paint on the area that you want to protect (Fig.24).
Then you only need to push the Unwrap button and click in Copy UVs. Now in the Tool palette select the original model (before the copy) and in the UV Master Palette click on Paste UV (Fig.25). Now our model has a UV to apply the textures to.
Now we need to convert the Polypaint to color map to apply the textures. Go to Tools > Texture Map and click on New From Poly Paint. This will convert the color information into one map. Then we can export this map by clicking on Clone Txtr and then going to the Texture tab and clicking Flip V (to invert our map) and then Export and Save (Fig.26).
I want to export one more map to help us in the 3ds Max. I'll export a Normal map as well containing the finer details; this way we don't need to export the full resolution model into 3ds Max. To do that I selected the division I wanted to export - in this case it was the division 5. Everything above this will be converted to normal map information. To create the map open Tool then the Normal map tab and then activate the Tangent and Smooth UV option. Then click on Create Normal map and the map will be created (Fig.27).
To export this map use the same process as you did for the Color map. Now export the model again using the same process as you did in the beginning using the Decimation Master. Don't forget to activate Keep UVs (Fig.28).
Back to 3ds Max. We need to change the old model for the new one so import the new one and delete the old one. Now is time to start our marble shader. Select a slot in the Material Editor (m) and then select VRay Fast SSS2 - it's an amazing shader for making translucent materials like skin or marble etc.
Use a preset to start with. In the preset options select Marble (white). Then change some of the parameters to improve the look (Fig.29).
Scale - additionally scales the subsurface scattering radius.
Overall color - controls the overall coloration for the material. This color serves as a filter for both the diffuse and the sub-surface component.
Diffuse color - the color of the diffuse portion of the material.
Diffuse amount - the amount for the diffuse component of the material. Note that this value in fact blends between the diffuse and sub-surface layers.
Scatter radius - controls the amount of light scattering in the material.
As you can see in the Specular amount I put 0, because I don't like to use the Specular for this shader. In my opinion there are too few options to control it so I'll blend it with a simple V-Ray material that has great Specular control. First create a simple V-Ray material and adjust the Specular color to a RGB with the value 30/30/30 to create a highlight with a little glossiness (Fig.30).
To make some tests with the new Specular, apply this material in the Override Mtl and click Render (Fig.31). When you look at the Specular it looks too regular and not realistic (Fig.32). To improve the Specular a little go to your Color map and open it in Photoshop. Remove the colors and apply some level adjustments until you create a map with the correct glossiness (Fig.33 - 34).
This creates an irregular Specular surface. In some places there will be more glossiness than others (Fig.35).
Now we have created a good looking Specular map we need to create a Blend material to mix both materials. Go to the Material Editor and select the VRay Fast SSS2 material and choose a V-Ray blend material. Click OK when it says "Keep old material as sub-material". Now click and drag the Specular material to the first slot in the material, and set the blend mode to 60% (Fig.36). After you finish the material duplicate it twice and apply it to the base of the statue and to the apple, and change the maps for their relative maps.
Now we have our material finished. The only change to make is some render parameters to give us a good quality render (Fig.37). Now we can have a coffee and relax a little until the render finishes!
Once this is finished you can do some color correction in Photoshop. And here is the final image (Fig.38).
I hope you enjoyed this chapter; next month I'll be back with a Roman style sculpture, talking about the differences and the process of making a Roman bust.