Fast Way to Achieve a Nice Digital Watercolor Render
By Majid Yagenegi
In this tutorial we are going to achieve a nice digital watercolor render using SketchUp and the render engine ‘TwilightRender’. We will also do a little post-processing with Photoshop (or your desired photo editor). This effect could also be achieved using any render engine that is based on MLT algorithm that will produce a whole vision of the scene while it is ‘noisy’. I have tried to use ‘noise’ as a possibility and part of the process.
As a painter, I personally prefer NPR rendering. Natural NPR SketchUp renderings are also amazing, but you may need some more artistic ones. If the answer is yes – this tutorial is for you.
Natural SketchUp renders don’t have any light source nor reflections, while Twilight renders could give us those goodies. I especially prefer those settings that are based on MLT algorithm because they will give you a sense of the whole picture, also with noise, which will certainly be sweet for our final result.
Step 1. After modeling I spent about 10 minutes to adjust materials and lights. Try to keep the main reflective surfaces and ignore minor ones. Then I add a HDRI for the environment and start rendering. Keep the render size matching the sketchup view as shown in the image below.
Step 2. The image below is a 4 minute render (originally 920 x 629 pixel, resized to 800 x 546, to be the same size of pure SketchUp output but with a tiny dots texture).
Step 3. Then I reduced the noise in Photoshop. You may also prefer Neat Image, that will keep the final result more colorized.
Step 4. Also we will need a pure SketchUp render. Here shown in the image below is an extended edge style with a green-blue dark sky.
Step 5. Now go to Photoshop (or your desired photo editor) to combine these two renders. The base image is pure SketchUp output . Then put the Twilight render over it and duplicate it so you have 3 layers. Here are layer settings:
Step 6. And this as well:
In Step 5 it shows the middle image has an Overlay blending mode with an opacity of about 50%, while the upper one in Step 6 has a Normal blending mode with an opacity of about 40%.
And here is the final result after merging all layers, and a bit of level adjustment. You may also be interested in using a texturizer filter to mimic a more realistic watercolor effect.
And here is the exterior image using the same technique.
Hope you find this short tutorial useful in your work-flow.