I am an admitted photography nerd- I spend much of my free time watching video tutorials or reading essays on the art and science of photography. Recently I find myself particularly fascinated with tutorials by Alex Koloskov from Kyiv, Ukraine at https://www.photigy.com He is a mad genius when it comes to still life product photography! His tutorials are on the pricey side, but he offers a free webinar every Friday for free online streaming. I've learned SO much from him in the last several months. I highly suggest you check out his site and YouTube channel if you want to see some cool stuff.
This week we are discussing "reflection vs. refraction": Reflection refers to a change in direction of light when it bounces off a substrate. Refraction is the change in the direction of light as it passes through a substrate. Imagine a bottle of beer in a tinted transparent bottle. The "reflected" light appears on the surface of the glass, reflecting the lights in the room the photograph is taken in. The "refracted" light is the light that bounces around *through* the glass and the liquid, creating highlights and shadows inside the object. Knowing how to control and manipulate the amount of reflections and refractions is essential to successful product photography.