cmiVFX-tutorial: Blender Greenscreen Keying Concepts

I would like to announce a new Blendervideo in the cmiVFX store:
Blender Greenscreen Keying Concepts.
It’s a cmiDirect, which means it is shorter (almost 2 hours) and focuses more on just this topic.
It covers keying, custom-keyers, channel-operation, lightwraps and some compositing techniques. You’ll find the press-release below.

cmiVFX Releases Blender GreenScreen Keying Concepts
High Definition Training Videos for the Visual Effects Industry

Princeton, NJ (January 27, 2011) – cmiVFX launches its latest cmiDirect training video for Blender. After the Blender 3D Compositing Training this is the second tutorial focusing on compositing with Blender. One essential task in compositing is green screen-keying. Placing an actor in a CG environment can be as important as creating the virtual set itself. The key to a convincing VFX shot with green screen footage is, well, a convincing key. Blender’s node-editor has all the tools you need for that. So to continue the Blender Compositing Series this cmiDirect video will show you how to do green screen-keying with Blender. When it comes to high end CG and VFX training, there is only once choice… cmiVFX! This video is only available here at the cmiVFX store!

Don’t forget about the cmiSubscription plan! Get one today. cmiVFX launched the most affordable subscription plan in Visual FX Training History for only $299 USD, and if you were a subscriber, this New Training Release would already be in your account. This video is also available a-la-cart in our brand new HTML5 player system.

Blender GreenScreen Keying Concepts

About this video
After integrating CGI into camera-tracked footage in the last training-video this time it’s all about integrating green screen footage into CGI or other footage. Blender’s node-editor is a great tool for that and offers a lot of freedom to either use the standard tools or to come up with some creative custom setups. We’ll focus primarily on different ways to create some great keys, but you’ll also learn some techniques how to get the best results out of your footage and to setup the final composite.

Standard Keying Tools
There are various keying nodes available in Blender’s node-editor. Often people try to use the color- or chroma-key, which surely are useful in some situations. The best key however is the channel-key, which is able to create decent mattes with fine edges. In this video you will learn how to use the channel-key to get a solid alpha-channel instantly, but also how to enhance and preprocess your footage to improve your key and create a smooth edge with lots of detail.

Custom Keyer
When the standard keying-nodes are not enough, you can still build your own keyer to fit your needs. Separating an image into different channels gives you a lot of control over each color and with some pixel math and rewiring you can come up with your own self made keys that sometimes work better and give more detail than the off-the-shelf solutions. Combined with garbage-mattes and rotoscoping you can solve even difficult shots with motion-blur, reflections and unevenly lit green screen.

But even the best alpha-channel will not help if your image suffers from color spill and doesn’t integrate well into the background. This video will show you how to enhance DV-footage to improve your key, how to get rid of color-spill and how to apply techniques like light wraps to really integrate your keyed footage into the background.

Once your key is ready you can either work with that directly in the compositor or save your keyed footage and use it in another composite. In the last chapter you will learn how to do that and how to apply some little post-processing tricks.

Please Note:

This tutorial is has been recorded with a development version of Blender 2.56a. There are still a few exciting months ahead until the final, stable version will be released. Bugs will be fixed, some little features might be added. But don’t worry! The techniques in this tutorial don’t rely on fancy tools, so you can use them with almost any version of Blender. But for reference we have included a current development version of the software in the project files.

Hey sebastian, super-cool, this was much needed!

I appreciate the trend of quality training. I hope BF evaluates and gathers these sources and put in the website officially.

Nice! Will have to check this one out.

Btw, did you use Matt Ebb’s camera patch? The perspective look way off, or that is one giant lady! :wink:

Indeed, this is one giant lady. :slight_smile: That footage is not even tracked, it’s just one image, and I simply placed her there deliberately and obviously didn’t get the scale right. But hey, that place is in Amsterdam, and if there is one place where you might get a distorted perspective, then there! :smiley: