Tag Archives: HDRI

How to create a HDRI image in Photoshop

Photoshop CC 25yrsPhotoshop can combine multiple images into one and save them as HDRI, which allows us to use them in our 3D renders – either as 360 degree backgrounds or as light sources.

The way to do it has changed several times over the years – so here’s how this works in Photoshop CC 2015.

Continue reading How to create a HDRI image in Photoshop





Where are the HDR images stored in KeyShot

keyshot-logoKeyShot comes with several pre-installed environments, based on HDR images. We can use them in other applications too, if we know where to look for them.

On a Mac, the KeyShot5 HDR images are stored here:

  • /Library/Application Support/KeyShot5/Environments

To navigate there, hit the Go option in your Finder, while holding down the OPTION / CMD key. This will bring up the Library option. Note that you must be in your system’s root Library folder, not in your user’s Library.

You can find your current path to those images, or even change it under Preferences – Folders:

screen-shot-2016-09-15-at-19-38-03

I don’t have the Windows version, but if you know it, leave it in the comments below.





Using Image Based Lighting (IBL) in Carrara

Coronet

To use Image Based Lighting in Carrara (IBL for short), we need a HDRI map (High Dynamic Rage Image). Using this technique your scene is not illuminated by light sources but rather by a weird looking image. This concept is known as Global Illumination and the results can be stunning (see above).

In principle, a spherical image is projected onto a dome around our scene, whose inner surface reflects the image back onto our scene, thereby illuminating it.

Several HDRI maps ship with Carrara, albeit buried deep inside the installation. I’ll show you how to hunt them down and how to use them in your scene.

Setting up the scene for use with HDRI

For those HDRI maps to work we need to prepare a few things in our scene. First we need to select the Scene (under Instances) and head over to atmosphere. IBL will only work with either a Sky or a Realistic Sky. Let’s select either of those options and configure them to your liking.

Screen Shot 2014-10-02 at 10.31.47

Under Background we need to add our HDRI map and configure its intensity (Background is just below Atmosphere in the same section):

Screen Shot 2014-10-02 at 10.35.12

Hunting down those HDRI maps

On Mac OS X the files we’re looking for are inside the App Bundle. Searching for them with Finder will not reveal them. Instead, open Finder and navigate to the actual Carrara app – mine is in Applications/DAZ 3D/Carrara 8.5 64-bit/Carrara.app

Once selected, right-click and choose “Show Package Contents”. A new Finder window opens, revealing yet more folders. Navigate to Contents/MacOS/Scenes/Global Illumination and you’ll find the following (among other things):

  • DoschHDRI.hdr
  • hdri-20_color.hdr
  • hdri-25_color W.hdr
  • snowfield2_color_small.hdr

Copy them somewhere that makes them easier accessible next time you want to use them.

On Windows it’s less complicated: the Scenes folder is inside the Carrara folder. On my system that’s  C:/Program Files/DAZ 3D/Carrara8.5/Scenes/Global Illumination

Render Settings

Over in the Render Room we’ll need to tell Carrara that we want to use Global Illumination. In the Rendering tab, find the Global Illumination section and select Sky Light, and optionally Indirect Light.

Screen Shot 2014-10-02 at 11.23.34

You also have a choice between Full Indirect Light and Ambient Occlusion, the latter will make for speedier renders with slightly softer shadows, the former will present very accurate results but takes a little longer to render.

Now go and globally illuminate something!