Sam: Lambertian Reflection

A lot of aspiring painters have a hard time with accurate rendering, whether painting from life or just out of their head.  So my first few posts will address some key properties of light and surface.
Some people seem to get this stuff intuitively.  I'm not one of those people, so I often have to figure things out.  One thing I've found that helps is working like a 3-d rendering program: thinking 3-dimensionally, rendering effects in passes, and in general isolating problems to deal with them separately.

So let's start with Lambertian Reflection, which is when a surface reflects light in a way that each part of the surface looks the same from every angle.
I purposefully used an ambiguous shape here, because what's important about this way of thinking is that you can solve literally any form in this way.  In the next few posts, I'll talk about different light sources, and then how this line of thinking applies to shadows and reflections.

Bookmark and Share

11 comments:

chromasketch said...

great analysis!

Scott Daly said...

Great post Sam! It's really helpful to get some review and another person's explanation for these types of things. I'm looking forward to more!

Randall Sly said...

Thanks Sam this was a great post!

Rochelle said...

Great stuff Sam! It's funny, I was wondering about Photons today when I saw the option in Maya. I've also always been curious about how to imagine light bouncing. Your Photon waterfall is certainly a great way for me to visualise it.
Thank you!

Michael Mercer said...

Um wow this blog is cool.

drunksaint said...

could you please enable full text feed on this blog?

Sami said...

Thanks to everybody for this blog. This is suuuuuper great :)

mirosouto.com said...

Very interessting your point of view, its an amazing way of how think.
Congratulations for the blog!

David McBride said...

Wonderful post!!! I am definitely one of those guys who does not get this concept intuitively.

Judy said...

Thank you, very helpful. I hope you will continue especially on practical terms, like how to translate into pencil (or other) tones. Judy

Dixon Leavitt said...

Thanks Sam! That was very helpful.

Related question: Since you've made it easy to find the diffused highlight (perpendicular to the termination line) do you by chance have an easy way to know where the specular highlight will be in relation to the termination line, or do you just sort of wing it?