THE MAKING OF GH HOUSE: DAYTIME RENDER TUTORIAL FOR SKETCHUP AND V-RAY

Software used: SketchUp, V-Ray for SketchUp, Photoshop, and Picasa

Note: For educational purposes, we will be using the ‘GH House’ model by Ronen Bekerman.

The purpose of this tutorial is to give you some tips and tricks, ideas as well as additional information pertaining to basic photorealistic rendering using V-Ray for SketchUp. In this tutorial, I will walk you through the process of rendering and post-production in order to create an accurate visualization. I did some experiments with the V-Ray for getting a good render output but was never satisfied with the result. Thus, I often use some photo-editing software such as Photoshop and Picasa. My experience and understanding on post-production technique enables me to enhance the raw render output producing such good quality image. For the knowledge of everyone, post-production is a process of editing raw images that enable to enhance the image based on your preferred compositional style output . On the other hand, rendering is the process that generates an image from 3D scene geometry you prepare in SketchUp.

In this tutorial, there will be a three-part discussion highlighting the procedures in rendering as well as post-production techniques. The first part will focus on SketchUp modelling, which is mainly the main core for adding texture and entourage to the scene. The second part will focus mainly on photorealistic rendering of a scene using Vray; this will include material editing and rendering set-up. On the last part of the tutorial, we will discuss the different post-production techniques using Photoshop and Picasa.

SKETCHUP

STEP 1: Open your SketchUp model. Here is the ‘GH House’ model as a sample. Set the view in perspective mode. Adjust your scene to ‘Shaded with texture’ with shadows turned on.

STEP 2: Import the following images in SketchUp. To do that, click File>import>select the image texture(s)> press Enter. You need to explode the imported images before you apply the texture(s) to your model. Some textures are available in the ‘Paint Bucket’ tool.

STEP 3: Apply the following textures in your SketchUp model. 

STEP 4: Insert 2D entourage in the scene.

STEP 5: Insert 3D entourage in the scene. The following entourage can be downloaded in 3Dwarehouse (the official repository website of all SketchUp users).

STEP 6: Set the ‘Camera’ in ‘Two-point perspective’ mode. This will enable us to avoid distortion when we start the rendering procedure.

STEP 7: After finding your preferred perspective view. Save your scene: view> animation> add scene. Creating a scene in SketchUp enables you to capture a state of model, thus you can go back to the same view and settings when needed.

VRAY

One of the most important steps in photorealistic rendering is applying the right materials to the model as it gives vibrancy to the whole scene. Some Vismat (V-Ray materials) are downloadable via internet. Here, I will show you the materials setting I used in this model.

STEP 1: Edit the following materials in ‘V-ray material editor’

(1) Pool Water

Pool water reflection settings

Pool water maps settings

Pool water bump map

       (2) Glass

Glass reflection settings

(3) Wood Deck

Wood deck reflection settings

Wood decks diffuse and map settings

STEP 2: Adjust the V-Ray render settings. This setting is based on the ‘default setting, I just slightly change some parameters.

     (1) Environment Settings

Follow the settings for the GI (Skylight). Here, the idea is to replace the V-Ray sun with HDRI from the GI (skylight) option. The HDRI will serve as the light source or sun. This will enable us to produce soft shadows. Adjust the value of intensity to 7.

Follow the settings for the ‘Background’. Here I used the same HDRI image from the GI skylight. Rotate the angle of the sky to 90 degrees. Adjust the value of intensity to 6.

HDRI Sky preview

(2) Camera settings

Adjust the value of ‘Film speed’ and ‘Zoom factor’. The ‘Film speed’ technically affects the brightness and softness of the render output, thus the greater the value of the film speed the brighter the image will occur.

(3)  Output settings

For the final render, adjust the resolution to 2560x2560. But, if you’re doing a test render, it would be better to start with low resolution first before adjusting to higher resolution.

STEP 3: Click the render button

Render time: 1 Hour and 9 minutes

Raw render image result using V-Ray

POST-PRODUCTION

This is my workflow in post-production and I use both Photoshop and Picasa to enhance my rendered image.

STEP 1: Using Photoshop, insert the entourage in your raw rendered image. To do that, open the tree branch entourage image in Photoshop> drag the image to your scene using ‘move tool’> place the entourage at the upper right corner> fit the entourage image using transform command (press Ctrl+T)> change the image view if needed (horizontal or vertical). Then save in JPEG Format.

Tree Branch Entourage

Result so far

STEP 2: Open your last image in Picasa and follow the workflow

(1)    Set to Orton mode

(2)    Sharpen the image

(3)    Apply Glow effect

(4)    Select ‘I’m feeling lucky’

(5)    Save in JPEG format

Result so far using Picasa 

STEP 3: Going back to Photoshop, open the last edited image and follow the workflow.

(1)    Adjust the ‘Color balance’

(2)    Adjust the ‘Vibrance’

(3)    Adjust the ’Hue and saturation’

(4)    Adjust the ‘curves’

(5) Adding Vignette on your image adds drama and makes the house model more accentuated.  To do that, duplicate the background (go to background layer> right click> click ‘duplicate’). Place the background copy at the top layer. Set the blend mode to multiply with 65% opacity. Using the ‘eraser’ tool remove the darker spot in the upper and middle portion of the image. 

As optional, you can hit CTRL+M (curve) again if you want to adjust the brightness and contrast of your image or go back to your layer and adjust the settings. I just want to remind you that the post-production settings may vary depending on your raw render image output.

FINAL RENDER OUTPUT

Thanks for taking the time to read the tutorial; I hope you will find it helpful to your future projects and presentation.