PRO way to have full control over your HDRI by splitting it into 2 parts, one will be sharper while the other a bit blurry, in order to produce softer shadows. Watch the tutorial below to learn this split HDRI technique.
Split HDRi Method
While working with 3ds Max and VRay, the HDRI-based lighting is arguably the best method for lighting your exterior scenes. But you’ll often find that not all HDR sky images you may purchase follow any common standard. The default exposure level and overall dynamic range varies.
That is why it’s important to have a workflow that allows greater control over the lighting. The split HDRI method aims to do just that.
The general idea behind this method is to create an additional blurry version of the HDR map.
PRO TIP: In photoshop you might get a really exposed image when you first open it up, so this is what you can do:
1. Put an “Exposure” adjustment layer and reduce the exposure till you see the sky and the clouds.
2. Blur your HDRI with the “Gaussian Blur” filter.
3. Delete the “Exposure” adjustment layer and save this “BLURRY HDRI” version alongside the original.
We’ll use this new blurry version to light our scene using the VRay Dome Light. By applying this blur we’ll be able to get softer shadows and a pleasing ambient effect. Since we don’t want a blurred sky showing up in our reflections, we’ll use the original HDRI for this purpose.
Load the original HDRI as well and place it in the ‘Environment Map’ slot in Max’s ‘Environment and Effects’ rollout. Remember to set the Dome Light as invisible and uncheck the ‘Affect Reflections’ setting.
Now all we need to do is balance the lighting level with the sky reflections. You can add a temporary chrome ball in your scene and tweak the Overall Multiplier value for the blurry HDRI to achieve the correct balance.
That’s it, try this method out, comment and share your results below. Don’t forget to subscribe for a regular dose of amazing professional tips and tricks.