3.2 Standard lights
While photometric lights may be the best choice for use with mental ray, it is possible to use the older-style standard lights, and you may very well have existing scenes you want to reuse without changing all the lights from standard to photometric.
In this chapter you will see that standard lights function correctly generally, but some situations require the adjustment of something called Physical Scale in the Exposure Control when you have photometric and standard lights mixed in the same scene.
You will also learn about a shadow map type called mr Shadow Map that, although it is a mental ray-specific function, may be used with standard lights to achieve shadow effects that are otherwise impossible.
In the first exercise, ...