Interior vray lighting

This is a tutorial for lighting an interior scene using Vray render. I don’t want to get into details of modeling or texturing or lightinf of an architectural scene. I only want to underline some details about lighting a particular scene. The aim is to outline one particular workflow for setting up lighting with Vray and should be viewed only as a guide for approaching similar interior scenes.

Lighting in the 3D industry is an art. There are many ways of lighting a scene. I like to control each one of the lights that are in the scene. For this reason I start from darkness setting lights one by one until I get the desired result. This kind of lighting method allows us to keep track of how each light contributes to the scene, before adding new ones. This also avoids having any unnecessary lights in the scene, that may cause unexpected results or increase render times.

We will start with Sky light, then add Sun light and finish with additional fill lights if required.

Preparation and Setup

1. We start selecting the Vray rende in Common/Assign Render

2. Set the render size to 320 X 240

3. In Render Dialogue uncheck Global Switches/Reflections – Refractions. We don’t want the reflections simples to be calculated since we are looking for a quick render.

4. Also we uncheck Default Lights

5. Image Sampler we set Fixed Rate: Subdivs = 1. You will have a poor quality render but good times for testing.

6. Let’s activate Indirect Ilumination (GI). Primary Bounces set to Irradiance Map. Use Irradiance Map Presets / Low. These default presets are good enough so for those who don’t have a deep experience feel free to use them.

7. For the moment set Secondary Bounces / None

8. Set Irradiance Map / Mode / Bucket mode. The render is divided into regions and each becomes visible when completed. This gives us a quick idea of the render. Sometimes I use Render Region when I am interested in a particular region.

For the moment if you click render you’ll get a black render because we don’t have any source of light in the scene.

9. So, don’t forget to Environment /Activate Override Max’s and set the Multiplier to 5 and the color to a very light blue.

10. Let’s make our first render.

We notice that there is a bit too dark and the scene is fill by a light color which doesn’t concern me for the moment.

Sunlight

1. Let’s create a direct Light that Hill be our sun. I used a Target Direct with Multiplier of 4, Activate Shadows / Vray Shadows. In Vray Shadow Parameter dialogue I activate Area Shadows, Box, UVM = 0,3.

2. We will try to colocate the Light so it can enter through the window. Make something similar.

3. Uncheck the Global Ilumination. We want to see how affects Light the scene and first of all where are the shadows.

4. Once we are satisfied with the result we activate the GI and make another render.

5. The combinación Sun Light (DIrect Light) and Skylight (Indirect Light) gives us enough light for this kind of interior. The render still has that blue Color Bleeding for the lack of reboted light(Secondary Bounces).

6. Let’s do that. Secondary Bounces / Quasi-Monte Carlo . Multiplier of 0,7, Subdiv = 8, Secondary Bounces = 2

In others scenes maybe we’ll need a higher value but after some tests I ‘ ve noticed that there were no big difference between 2 and higher values (for this scene). So we will let it in 2. Make another Render to see the result with reboted light.

Now the render is starting to look better.

Fill Lights

1. Let’s create another Light with smaller values in order to fill the whole scene.

1. We create an Vray Light with the size of the window. Be sure to have the light normals into the interior of the room. Activate invisible. Multiply to 2 and the type Plane. We put the Light just near the window without touching it.

2. and Render.

Our scene is now prepared for the final render.

Render Final

1. Activate the reflexions in the Global Switches panel
2. In Image Sampler change to Adaptive subdivisión with min = -1; max = 2.
3. Irradiance Map use the preset High
4. Render size 720×486
5. Render
6. Save the render with 32 bits alpha channel for a little postproduction and add a background to the window.

Postproduction

1. Even Vray gives very good results I always make little adjustments in Photoshop so open it and import our final render.
2. Let’s work the leves. Image/Adjustments/Levels.

3. Duplicate the background and Desaturate. Now we have a layer black and white. Adjust the levels to acentúate more the balcks and the whites of the image. Change Normal mode to Color Burn and opacity to 20%.

4. Choose an image for your background and import.

5. CTRL+A to select all. CTRL+C to copy and activate our file and CTRL + V to paste the background. A new layer with the background image is created. Move it down to the snack beneath the others layers. In order to move the image beneath the background layer, double-click over the background layer and OK. Now you can move the image layer beneath the background layer.
6. In the Channels window we will find the layer Alpha 1. With the CTRL button and the left button of the mouse we click the layer and select all the layer. CTRL+SHIFT+I to invert the select zone and delete. Without loosing the selection we activate the black and white layer and again delete. Now we have the background image in our window. Now try to find the best view.
7. Adjust the leveles. Sometimes I put a white layer below and play with the opacity. Here I have the white layer and the opacity set to 15%. Add a Gaussian Blur of 0,3.
8. This is it. You can go on trying others filters: Film Grain, Lens Correction, DOF, blurs. I am happy with the result here so this the final image.

I hope this tutorial is practical to you guys.
I am preparing another tutorial about IES lights. Stay close.