Welcome back. This is the third in a set of tutorials where you’ll learn how to produce industry standard 3D Renders/ Visualisations of your product concepts.
Product Visualisation – The Studio Environment Vol.1
Product Visualisation – The Studio Environment Vol.2
Product Visualisation – The Studio Environment Vol.3 (Currently Reading)
Product Visualisation – The Studio Environment Vol.4
If you are new to this set of tutorials and would like to follow along, I suggest you start with Tutorial 1 – The Built Environment and Tutorial 2 – Materials & Textures for previous steps.
For those who are unfamiliar, this is a tutorial written for beginners and students. As such, we will discuss the theory behind the concepts as well as the execution. Over the course of the four tutorials, we’ll cover the necessary skills to create this scene.
So with arms aloft, let there be light.
The Requirements
Difficulty: Beginner/ Intermediate
1. To open the example file, you will need 3DS Max 2009 and V-Ray 1.5SP2 or above. Download the example file at the end of each tutorial.
2. If you use the example file, please understand that the contents should not be redistributed in any way. Similarly, the content is not allowed to be used for commercial purposes.
Tutorial 3 – Lighting
Overview
In the last tutorial we explored VRay materials, and in particular, three parameters – Diffuse, Reflection and Refraction. We also discussed texture maps – how they relate to VRay materials and how to control them on our objects.
However, you might have found that the materials we created in Tutorial 2 – Materials & Textures looked somewhat dull and flat. This is thankfully where lighting the scene comes in. Due to the lack of directional light, our objects don’t have sharp highlights on them, making them appear less realistic. In this tutorial, our materials will come into full effect. To achieve this, we will be learning about various lighting techniques – exploring their basic parameters and scenarios in which they can be used.
2 Cents: Materials & Textures can be viewed as the practical element – accurately describing what the product looks and feels like. Lighting however is about creating mood and atmosphere. It is often a more creative and free form task, with fewer guidelines. This can be a boon to some and a pitfall to others. So loosen up and get ready to experiment, and read.
Here’s a listed overview of the contents and topics this week.
Lighting Types
Global Illumination (Skylight)
VRay Lights
Lighting Setup Examples
Creating Scene Lights
Global Illumination
VRay Light
After completing Tutorial 3 – Lighting, our scene should look similar to this.
1.0 – Lighting Methods
Before we commit, here’s a quick spiel about the different methods of lighting and what we’ll be dealing with in this tutorial.
There are several ways to light a scene. A tutorial will usually only show you one method to complete a task. Unfortunately, another tutorial will preach another method of doing the same task. The best option is to learn the method, try it and then decide whether it’s the most effective for you. It’s for that reason it’s important to use this set of tutorials as a guide, not a rule book.
In this installment we will be looking at using a combination of VRay lights and Global Illumination – indirect lighting – which we’ll look at first.
Note: Sources/ links will be provided for image references. There’s no point in me rewriting the material because it is described perfectly in these other sources.
1.1 – Global Illumination (Indirect Light)
Renderers that use Indirect Illumination/ Global Illumination algorithms take into account not only the light coming directly from light sources (direct light), but also the light that is bounced of from all surfaces and all of the following light bounces until infinity (indirect light). This bouncing off surfaces makes the rendering more realistic, because it simulates the real movement of light. GI is commonly used acronym for Global Illumination.
You will need to have Indirect Illumination (GI) turned on in your VRay settings for it to calculate GI. In the first tutorial we already turned this on when applying our VRay test settings. All of our renders thus far have used Global Illumination.
The example image below uses the default Max scanline renderer, a non GI renderer. There is only one light source and all the areas in shadow receive no light. This is because no light is being bounced off surfaces and reaching those areas.
Pretty ghastly, let’s keep using VRay. We will explore GI through three parameters – Background Colour, GI Skylight Override and Reflection/ Refraction Override.
1.1.1 – GI Environment Override (Skylight)
There are two places that you can adjust your environment settings and the amount of GI light in the scene. The first is the Environment rollout in the VRay settings and the other in the default Max Environment dialog box (Go to Rendering > Environment). First up, we’ll discuss the Max Environment dialog box, and the Background Colour option.
Using the Background Colour is similar to most; you can choose a colour or map to define the parameter. When used in combination with the VRay renderer (and GI Skylight Override is turned off) this acts as the amount of light in the scene as well as the colour of the background. This is very important.
Look at the two examples below. I’ve hidden our rounded wall and put the objects on a plane so we can see the background. Plus, in the VRay Environment rollout I’ve turned off the GI Skylight Override so that the Max background colour affects the light levels.
I’ve only changed the background colour in the images. The background colour is white in one picture and dark grey in the other. You can see that it not only affects the colour of the background/ environment, but it also affects the amount of light in the scene.
Example 1 – Background colour is white.
Example 2 – Background colour is dark grey. Note that If it was black we wouldn’t be able to see anything.
This is where the GI Skylight Override comes in. To get more control over the background and the amount of light in the scene, you can use the ‘GI Environment (Skylight) Override’ option in the ‘Environment’ rollout in your VRay settings.
When on, this works like a sky that emits light from all directions. It overrides the background colour letting you control the level of GI light in your scene without affecting the background colour, and vice-versa. For example, if your background colour is black and your GI Skylight Override is white, your scene will have lots of light in it but your objects will still be reflecting a black background/ environment.
Look at the two example images below. I’ve unhidden the rounded wall and deleted the plane so you can see the affect on the objects and not the background. Both images have Skylight Override turned on and the colour set to white. This makes the background colour have no affect on the amount of light in the scene anymore; it only acts as the environment which your objects reflect. Only the background colour is different in each example, and the objects reflect differently.
Example 1 – GI Skylight is white, background colour set to black.
Example 2 – GI Skylight is white, background colour set to white. Theses are the settings we’ve been working with.
To summarise:
- Background colour changes the colour of your background/ environment and can be used to affect light level.
- GI Skylight Override only changes light level by ignoring/ overriding background colour.
It’s crucial that you understand the distinguishing features of these two parameters. Play around with it, practice makes perfect. Once you’re done, return to our default setting – GI Skylight Override on with colour set to white, and background colour also set to white.
1.1.3 – Reflection/ Refraction Override
The last parameter we’ll be looking at is the Reflection/ Refraction Override.
In the previous section, the Skylight Override only controlled the amount of light. The background colour however, remained as our environment which came up in the reflections of our objects.
This new parameter gives us even more control of our environment by letting us override these reflections and refractions created by our background colour. By turning it on, you are creating a ‘fake’ environment for your objects to reflect. In your render however, you will only ever see the colour or map that is set in your background options.
Let’s take a look at the effect of this parameter by utilising its map slot now. Look at the two examples below. In both examples I’ve put a VRay HDRI map only in the Reflection/ Refraction Override slot, with a different HDR Image in each example.
Note: For those unfamiliar, a HDRI is a High Dynamic Range Image. It is often a 360 degree view image of an environment. It is used to give a scene realistic reflections and illumination by simulating an entire environment without it physically being there. We will not be going into HDRI’s in this tutorial; it will only serve as an example.
The background colour has also been set to a flat green and the objects have been placed on a plane again so you can observe the background. Additionally, a sphere with a chrome material has been placed in the scene so you can observe reflections. Let’s see how it looks.
Example 1 – GI Skylight Override set to white, studio environment HDRI in Reflection/ Refraction Override map slot, background colour set to green.
HDR Image
Rendered Result
Example 2 – GI Skylight Override set to white, landscape exterior environment HDRI in Reflection/ Refraction Override map slot, background colour set to green.
HDR Image
Rendered Result
By using the Reflection/ Refraction Override, you will notice the objects in each render reflect completely different environments eventhough the background is a flat green. This is to show you that with both overrides on – reflection/ refraction and skylight – the background colour has no bearing on the scene anymore. It now doesn’t affect the light or the reflections, only what appears in the background of the rendered image. You’ll only be able to see the HDRI in the background if you add the VRay HDRI map to the Background Colour slot.
To summarise:
Using the three options – Background Colour, GI Skylight Override and Reflection/ Refraction Override, you can control the fundamental elements of your environment independently.
We’ve now finished looking at Global Illumination and GI environment lighting. Let’s mosey onto VRay lights now.
1.2 – VRay Lights (Direct Light)
With VRay comes its own set of VRay lights. These are specifically built to work with the VRay rendering engine for improved rendering times. The settings or options associated with VRay lights are easy to understand and use. There aren’t as many options to deal with compared to Standard or Photometric lights, which makes things easy.
In the section we will be covering the fundamental parameters in VRay lights including the Type, Intensity Multiplier and Colour. We’ll also briefly look at other significant options. We’ll discuss creating and positioning light further down.
Note: Most of them don’t require image examples and are self-explanatory but if you do, refer to the link in the Additional Reading section.
1.2.1 – Type
VRay lights come in three different types, which specify the shape of the light and can be selected from the ‘Type’ dropdown option. These are Plane, Sphere and Dome.
Plane – Has the shape of a planar rectangle and is defined by length and width.
Sphere – Has the shape of a sphere and is defined by the size of its radius.
Dome – Acts like a Skylight. It creates a hemispherical dome from which light is emitted from all points. The dome is created above the Z axis of the light. A texture map like a HDRI can be added to the dome light, just like the Skylight in our Environment setting. This is known as Image-Based Lighting (IBL).
1.2.2 – Multiplier/ Colour/ Size
I’m sure you are more than familiar with the multiplier and colour parameters at this point.
Colour – Using the swatch will determine the colour of the light.
Multiplier – Refers to how many times the light colour is multiplied.
The size parameters are slightly more complex but very useful.
Size – Determines the length, width or radius of a light. As a general rule the size of the light also determines the blurriness of the shadows. Smaller lights means crisper shadows while larger lights mean blurrier or more diffused shadows. This is a very important visual effect.
1.2.3 – Options
Here we’ll look at some of the highlights of the options section.
Cast Shadows – When on (the default), the light casts shadows. Turn this option off to disable shadow casting for the light.
Affect Diffuse – Determines whether the light is affecting the diffuse properties of the materials.
Affect Specular – Determines whether the light is affecting the specular of the materials.
Affect Reflections – Determines whether the light will appear in reflections of materials.
Some other parameters of note are:
Subdivs – We’ve covered Subdivs before and have seen its effect on the quality of materials. Lights are no different – lower values mean more noisy results, but will render faster. Higher values produce smoother results but take more time. As a general rule, this can be seen as the render quality of the light.
Use Texture – When the Rectangle, Dome or Plane light type is used, this tells the light to use a texture map for the surface of the light.
Texture – Specifies the texture to use. The texture intensity is also affected by the Multiplier of the light.
We’ve now finished looking at VRay lights, and with that, have completed the fundamentals of lighting methods for this tutorial.
1.2.4 – Additional Reading
To get even more familiar with lights, read this documentation about VRay light parameters at Spot 3D.
Also, take a look at their lighting image examples. This is very useful if you want to see some of the parameters we’ve talked about at work.
2.0 – Lighting Setup Examples
Now that we’ve discussed how to setup and control the GI Environment, and the various parameters and features of VRay lights, let’s take a look at them in action. Here are some different ways to approach a lighting setup and the rendered result. I’ve included this section to demonstrate the significance of the type, positioning and settings of lights you choose. It’s also very important to note different ways of approaching the same task.
Note: These examples use Exponential Colour Mapping and the VRay Curves Correction which we have not discussed yet. Not to worry, we will go over this a bit further down.
Example 1 –
• Dark grey Reflection/ Refraction Override.
• Mid grey GI Skylight Override.
• 2 white VRay plane lights from left and right.
Setup Screenshot
Rendered Result
Example 2 –
• Dark grey Reflection/ Refraction Override.
• Mid grey GI Skylight Override.
• 2 coloured VRay plane lights from left (orange) and right (blue).
• 1 Standard Target Directional Light.
Setup Screenshot
Rendered Result
Example 3 –
• 1 VRay dome light using HDRI as texture map.
• 1 Standard Target Directional Light
Setup Screenshot
Rendered Result
You will notice that each example has its own subtle and not so subtle differences. While the overall scene is the same, it’s evident for example, that the coloured lights in Example 2 have a subtle tonal impact on the mood of the scene. Similarly, in Example 3, the HDRI used in the Dome Light has quite a different approach to reflections. You will also notice that the reflections, and particularly shadows, created by Target Directional lights differ from VRay lights.
The final lighting setup we’ll continue with next is by no means the best, which is exactly the point. It comes down to it being a matter of preference. The final setup is only chosen because it is simple and uses methods we have discussed – VRay plane lights and basic GI lighting.
We’ve now finished with lighting setup examples.
3.0 – Creating Scene Lights
Having just seen some final rendered examples and using the lighting methods we’ve explored, we’ll now create the actual lights that will feature in our scene.
1. Environment Light – GI Skylight
2. VRay Lights – VRay Plane
2 Cents: Creating good lighting, at any skill level, might have to be a trial and error process, but it’s the best way to learn. There are also dodgy shortcuts and work-arounds which you will resort to, to get the job done. There’s nothing wrong with this. Be as shady as a back street merchant as long as the end result looks good and communicates the product/ concept effectively. In this tutorial you are given the settings, but I can assure you that this required both trial and error on my half.
Let’s create the lighting for our scene.
3.1 – GI Light
GI Environment Light in this scene is very simple. Like discussed before, we want a dark environment to simulate a photo shoot. In this case, we will use the Reflection/ Refraction override so our objects reflect a dark environment.
• Go to the Environment rollout in your VRay settings.
• Turn on the Reflection/Refraction Override if it isn’t already, and set the colour to a dark grey. (RGB: 50, 50, 50)
However, we need our lighting to levels to be reasonable so we can set the GI Skylight Override to something slightly lighter.
• Once again in your Environment rollout, turn on the GI Skylight Override if it isn’t already and set the colour to a grey. (RGB: 90, 90, 90)
Note that it does not matter what we set in our background colour because you will not see it in the render. Our rounded wall is blocking out the background.
We’ve now set up the GI Environment Lighting for our scene.
3.2 – VRay Light
All this talk about lights and we haven’t even made one yet. In case you don’t know, there’s not much to it really. It’s like creating any other primitive. In this setup we will be creating three plane lights, 2 large and 1 small. The two large planes will act as fill lights and the smaller plane will be used to produce the main shadow – a bit sharper.
• Go to the ‘Create’ tab, select ‘Lights’ and the select ‘VRay’ from the dropdown menu.
• Click ‘VRay Light’. This will open up its options and the button will be highlighted yellow so you know what you are creating. Select ‘Plane’ from the ‘Type’ dropdown.
• Now in one of your Viewports, click and drag your mouse to create the light, and specify its size. These properties can obviously be adjusted later.
• Create 3 VRay plane lights in total. Don’t worry about the positioning for now. Don’t scale them either using the transform gizmo, this will interfere with the unit scaling. We will assign them a size through the settings.
• Apply these three different setting options to each of the lights we just created. Make sure to use ‘Luminous Power’ for the Units parameter. From left to right, the lights are Light 1, Light 2 and Light 3.
• Now position your lights similar to the images below.
We’ve now successfully set up the all the lights required for our scene.
4.0 – Render Update 1
Let’s see our final efforts at work. With all the preparations for our lights and environment lighting completed, it is time for an updated render. Hit the Render button.
It’s an outrage! Admittedly, it’s not looking remotely like the previous rendered examples. That’s because we still have a few key changes to make and this is where we make them. To correct the scene we will have to adjust our Colour Mapping, tweak our materials and use the Curves Correction output in the frame buffer.
4.1 – Colour Mapping
Let’s start with Color Mapping. This is a rollout you will find in your VRay settings. It is used to apply color transformations to the final image colors. This can have a significant effect on the rendered result. Tutorial 4 – Cameras & Rendering will cover Colour Mapping in more detail. Suffice to say, we need to change it from Linear Multiply to Exponential.
• Go to your Colour Mapping rollout and select ‘Exponential’ from the ‘Type’ dropdown list.
(Image: Exponential Colour Mapping)
• Change the Bright multiplier to 5.0.
• Hit the Render button.
Alright, it’s only made a slight change, but if the lights were brighter in the scene the Linear Multiply mode would make the surfaces look over exposed and burnt out. Using Exponential Colour Mapping mode will counter this significantly.
4.2 – Material Correction
However, I’m not completely happy with the material of the White Porcelain. The surface is too reflective and also requires a falloff on the reflection. Let’s take a look at that.
• Locate the ‘Porcelain White’ material in your material editor.
• Click the map slot for Reflection and add a ‘Falloff’ map.
• In the Falloff map settings, set the second colour to a dark grey (RGB: 50, 50, 50).
• Hit the Render button.
Much better! You can see that the reflection is more subtle and looks more accurate. The Falloff map has also made the reflections tail off towards the edges. This is because the Falloff map is essentially a gradient, which we specified goes from black to a dark grey.
4.1 – Curves Correction
The overall scene is still quite dark however and we need to brighten it up. You are welcome to spend time making the lighting levels perfect. You could for example just turn the Bright Multiplier up on the Colour Mapping settings. However, this section is about demonstrating some other tools to help you quickly adjust your render output. One such way is through the frame buffer you see every time you render.
When we applied our VRay test settings we turned on the VRay frame buffer in the ‘VRay: Frame Buffer’ rollout of the VRay settings.
This is much more useful than the standard Max frame buffer and can be used to adjust various level settings. One I find is particularly useful is the Curves Correction. With it you can adjust the highlights, midtones and shadows of the rendered image. If you’re familiar with Photoshop you might already be aware of image adjustment modes like this.
Let’s add the final flourish and be done with this.
• In the VRay frame buffer, click the ‘Use Colour Curves Correction’ button and the ‘Show Corrections Control’ button.
A box will pop with a few settings. Among them you will see a type of graph with a spline, currently just a line. It’s reasonably simple, split the graph into three sections. The lower end – bottom left represents the shadows. The higher end – top right represents highlights. The area in the middle represents midtones.
By clicking the end points of the line you are shown a ‘spline handle’. You can drag this around to adjust the curvature of the spline.
• Adjust the end points of the spline to look similar to the image below.
If you want, play around with other adjustment options, till your happy with the result. Let’s take a look at the unadjusted image and the final image using the Colour Curves Correction.
Huzzah! The curves correction has tweaked out the lighting levels. I’d say the GI and light sources are correctly and sufficiently illuminating our scene now, still creating a smooth infinite white space. Congratulations on a commendable effort.
We’ve now completed Tutorial 3 – Lighting.
5.0 – Summary
We’ve discussed the fundamentals of VRay lights and the mechanics of Global Illumination. We’ve also managed to look at placing lights and how their intensity and options can have a significant effect on the render. With the lighting set up for our scene, the end is in sight.
Using our environment, materials and lighting, we will explore the possibilities of cameras and customised render settings next week in Tutorial 4 – Cameras & Rendering.
If you would like to see more work from this project and others, you can visit Kooque. I can only hope that this has been an illuminating experience – pun very much intended – and that you return for the next and final installment.
6.0 – Source Files
Here are the source files for this and previous tutorials.
Ink.zip – Contains MAX file with 3D model.
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Awesome tutorial, thanks!