How to Improve your 3D renders: Adding dust in Keyshot.

If you render out a 3D product on your computer, everything about it will look absolutely perfect. But if you want to create a more photorealistic product render, you have to understand that the world around us is not perfect. Objects contain, amongst other things, scratches, dents, smudges and dust. Those imperfection that come for granted in the real world, are things you will have to create yourself if you make a 3D product render. In this article I will show you how you can add dust on your objects using Keyshot.

So first things first. I assume you already have your product set up in Keyshot with all the right materials and lighting set up. In my example I will be using the render you see below. I will be adding dust to the object surfaces of this model.

To create dust we will perform the following 2 steps:

1. Create a grayish plastic label material, to place over the base material.
2. Apply a mask to the label material, to give the label the appearance of dust.

Create a label material

So to do this we go to our object’s material (in this example I have made a blank material and called it Dust Example). Now go to the Labels tab and press on the Add Label plus sign and slect Add Material. This will add a blank plastic material. In the image below you can see that I have added my label material and renamed it Dust Label.

You can change the label material’s color in the label properties tab. Change it to a neutral gray (e.g. HSV value of 0:0:55).

Apply a black and white mask texture

Now the next thing we need is an image like the example below. This is a black and white dust mask texture. You can get these at several texture sites on the internet, (e.g. poliigon.com).

Attach the texture to the bump and opacity channels

We will attach this texture to the Bump and the Opacity property channel of the label material. Attaching it to the Opacity channel will make sure that only the non black parts of the image (the dust) is visible. Adding it to the bump channel will make sure that the dust will look like it is lying on top of the base material. Below you can see the whole shader network.

What you might notice is that I have added a color to number node in-between the dust texture and the opacity channel. With this node I can control the opacity. In the node I have set the max output color to a value of 0.5. Which means the output color will not surpass a 50% grayish color, so the dust does not become too bright white. This was just a personal preference for this example, but using the color to number node is good practice to control the opacity. Below you see a preview of the texture on the model with the color to number node at 0.5 and at 1.0 (which is basically the original texture):

Copy the dust shader network to every material required

So the next step would be to copy the whole Dust label shader network (the Dust texture, Color to number and Dust label node) in the materials Graph editor, and copy and paste this into all the other materials where there should be dust on. You can just copy and past the Dust label shader network and attach it to the label channel of each required material in the Graph editor. I already had all my materials set up. So after copy and pasting the dust label in all the other materials I obtain my final dusty result. You can see the before and after comparison below.

If you would like to know more, please get in touch. Or leave any questions or remarks in the comments below?