Binary Alpha is a very simple, yet super convenient expression that I use all the time, and decided to turn into a quick gizmo.

It analyzes a choice of the RGB, RGBA, or Alpha input and outputs an Alpha Channel (or RGBA result) that is Binary, 0 or 1.  Any Pixels that are not 0 will be turned into 1 (negative numbers also), and 0 will remain 0.  

This is perfect for those “blur, unpremult, set alpha, blur” for tricks extending colors, or if you need a quick matte for finding any rgb color above or below 0, in a CG render passes for example.

The good ol’ blur/unpremult/blur ❤ :


Basic properties:


The literal tcl expression is just:

r!=0 || g!=0 || b!=0 || a! = 0 ? 1 : 0

Which in english, translates to something like: 
“if red is not 0, or green is not 0, or blue is not 0, or alpha is not 0, then be 1, or else, be 0”
So it will include negative pixels as an output as 1 as well.

Super simple but hopefully a time saver if you are like me and hate remembering expressions.

Find the tool on nukepedia here:

You can also download this tool at my github, where you’ll find all my public tools in one place:


Advanced Keying Breakdown: DESPILL 2.1 Initial Concepts

0:00 intro
0:40 what is despill?
3:40 Separating the Despill process from the Alpha process
7:33 Core Despill and Edge Despill

Hey guys,

I’m going over the first section of Despilling.  I talk about what despill is, why you need to remove it,  how it should be separated from the alpha process, and combining core and edge despills.

The 2 main goals of despilling are:

1.) Removing any spill while still maintaining the original colors in the plate
2.) Blending the subjects edges with a BG colors

Here is the link to a great despill tutorial which goes over blending BG colors using the difference matte of a despilled plate –> to the original plate.   If you are new to the concept of blending your despill with the background then you are really going to like this video.  He talks about flame in the beginning of the video and switches to nuke later.

Thanks for watching, next I’ll go over how to achieve and control the despill to get what you need.

– Tony

Advanced Keying Breakdown – ALPHA 1.1: pre-processing the GS

Here is the first part in the advanced keying series.  I’ve started with the ALPHA section, and made a custom slide for just ALPHA, where you can see the many topics I plan on covering in future videos, but for now I am just covering 1.1 Pre-processing the Green Screen.  Here is the slide for ALPHA:

Advanced Keying Breakdown_ALPHA_detail_v01

It’s a long video, but it’s full of useful tips and techniques.  I recommend watching the whole thing if you get a chance, but if you’re in a rush and want to skip to certain sections here are the Timecodes for you:

0:00 Intro

1:12   Denoising

5:56  Colorspaces

13:11 White Balancing

21:28 Saturation

25:33 Evening out the GS

35:21 Outro Recap

here is the Neat Video plugin website I mentioned for reducing noise on an image:

here is the link to some keying tutorials from nuke station for you guys to look through if you need them, most all of them are excellent:

Please guys, I know I covered a lot but if you have any questions, or if you would like me to do a written recap on all the sections here in this blog post, please just let me know and I’d be happy to write it up for you.   Leave a comment with any questions, or if you think I messed something up, or if you’d like to contribute to the conversation and have anything to add to this tutorial.  I enjoyed putting this together and look forward to the rest of the keying tutorials I plan on putting together.  Please share if you learned something =)