Using and mastering IBL concepts takes some practice. If you are new to rendering, you should start using Physical Sky as your primary exterior lighting option because it is so easy to use and set up.
Image-based lighting offers unique exterior lighting options based on real-world locations and light. Using special cameras, photographers can capture the metrics of light (strength, quality, and color) in a real-world scene (Fig. 23.3). These specially captured images can be inserted into IRPs that offer this option. Once they are inserted, the IRP references the light data in the image to simulate the exact lighting in the rendering (Fig. 23.4, Fig. 23.5, Fig. 23.6).
The IBL format typically used for these types of photographs is called high dynamic range images (HDRI). Compared to Physical Sky settings, HDRI images can generate more realistic lighting ...