Leather is one of the most used materials in the field of furniture design, especially for design of sofas or couches. It is quite easy to obtain a good leather material, although the leather material quality strongly depends on the illumination in your scene (Fig.01 – Fig.03).
Before you start to create the leather in the material editor, you must first analyze exactly what type of leather you want to simulate in 3D Studio Max. Once you've made this decision, choose an image which has the pattern/texture of the real leather. In Fig.04 you can see examples of images/maps which allow us to create a perfect leather texture in the material editor. The first one is a simple image of scanned paper, which we used to create leather in Fig.01; the second one is made with Photoshop, which was used to create leather in Fig.02.
This image is used for image 2 This image is used for image 1
Now let's look at the steps to create leather. First you want to add the correct specular highlights. You must analyse the real leather and simulate the same glossiness and specular level in the material editor. There are no standard values. These settings depend on the type of leather and also on the illumination. If your light is very bright, you will have a very strong specular highlight in the rendering. To avoid this you must set a lower amount in the specular level slot. In the diffuse slot choose the colour of your leather material.
Now go to Maps > Bump and click on the None button.
The Bump map now allows you to create the leather texture. At this point you have many different kinds of maps that you can choose from. In this tutorial we will use or the Bitmap or the Noise map. Both are very useful.
If you choose Noise map, you must pay attention to only one parameter: the size of the Noise map. Usually it's very, very small; often lower than the value 1. But again, this value depends on the kind of leather that you want to simulate.
In the Bump amount slot, you are able to set the strength of the texture. Normally it is never more than 50/-50. In Fig.03 you can see the result of the Noise map (Fig.05).
Fig. 05 (BITMAP or the NOISE in the Bump slot)
If you choose to assign a Bitmap (an image) to the Bump slot then you must be aware of the tiling value. It has more or less the same effect as the size parameter in the Noise map (you can also assign a UVW Map to the object from the modifier list and change the Gizmo size; it will have a similar effect as tiling).
Once you have completed the scene, to have more control over the specular highlights in the rendering you can use a special "MR Area Omni" light. After you have placed the light in the correct location, right-click on the MR Area Omni and disable "Affect Diffuse" (Fig.06).
Fig. 06 (additional lights for additional highlights)
After this step the MR Area Omni will only create specular highlights on the materials. We will use that MR Area Omni to create the highlights that are normally visible on leather. In this way we have much more control of the position, colour and brightness of the specular highlights.
Disable shadows in the MR Area Omni. This technique can be very helpful if you need more highlights than the existing light sources are already creating on the leather material. To avoid this light affecting all objects in the scene, you should use the exclude option in the modify panel. This excludes all other objects which should not receive any additional highlights (you must select the light to do this)
Now let's look at how to create the leather texture shown in Fig.01.
Go to Photoshop and create a new file. From the main tool bar, go to Filter > Texture > Stained Glass (Fig.07).