https://visualeducation.com/class/live-workshop-polarising-studio-light-and-why/

 

Polarising studio light can be incredibly useful in commercial photography. But you have to know why, when and how to do it.  This knowledge will equip you with an extra level of control, which is particularly useful when shooting reflective or shiny surfaces, or even shots with multiple surface textures.  In this class, Karl explains what polarised light is and demonstrates how it works through three different practical shoots. He explains the difference between polarising your light and polarising the lens, what each does, and what happens when you do both.