What Is Linear Workflow and How Can It Help Your Renders Look Better?

November 1, 2010 - By 

I wanted to start a conversation about Linear Workflow. It’s a topic that leaves a lot of people (including me) confused and asking a lot of questions. Why now? Well, with Cinema 4D version 12, linear workflow is turned on by default. And, with After Effects having linear workflow for a few years now, this is the perfect time to learn about LW and set up a true linear workflow for your renders. I have spent the last month doing a bit of research about working linearly and have tried to boil down where my mind is on the topic in the video above. I still have a lot to learn, but I figure we can start talking about it and learning from each other.

Why Bother?
You may be thinking, “Why should you go though all this hassle? My images looked fine before, why change now”? While linear workflow is a bit confusing at first, it will pay off BIG TIME in the long run. Your images will look more natural and your composites will be even easier. Besides, this is how computer graphics should have been in the first place. Computer graphics is relatively new and everything you know till now is a hack to make things work with antiquated technology. Linear workflow finally brings realistic light addition and falloff to your renders. The worst thing you can do is go back to your non-linear ways and pretend that linear just doesn’t exist. It’s here to help you. Hug and embrace linear workflow. It’s here to help, not to hurt.

Why Is This Crap So Confusing?
Learning about linear workflow gets confusing for a few reasons.

1. There are a lot of variables that go into a true linear workflow. Just flipping a button in your settings won’t do it. A true LW means that your images, video, textures, hdri images, renders, composites and effects must all be make linear and calculated linear at every step of the process. And since motion design and VFX is all about combining all of these different mediums, there is a lot of chance for error and confusion.

2. Computer monitors are lying to you. This means we have to apply a gamma curve to your final image to display it correctly on these screwed up monitors. The problem is, these gamma corrected images are then used in composites and not corrected back to linear before calculations are applied to them. When those images are RE-gamma corrected, the result is images that are too dark or too bright.

3. Before and after comparisons don’t do much to help explain what is happening behind the scenes. Sometimes scenes are darker with linear turned on, sometimes scenes get brighter. There just isn’t an easy visual way to explain it.

Useless Comparison Image

4. All your old tricks don’t work. With Linear workflow, things behave WAY differently. All of your old lighting, compositing and reflection tricks don’t work. Your old tricks are now broken because linear workflow calculates everything much differently. This is a big one for people and it’s a huge reason people have been shutting off linear workflow. Dont! Trust me, you don’t want to hold on to your old tricks. They were based on bad math. Linear workflow is here to make things easier, but it’s at the expense of your old tricks. [This is, by the way, why there are two rigs in the HDRI Light Kit Pro for many of the lights. One for working in linear and one for working non linear.]

How Can I Learn More?
There really isn’t a whole lot of information out there about Linear Workflow. I have found a few reliable resources that have helped me understand what linear is all about. Check out the links below to learn more about linear workflow.

FX Guide Podcast with Master Zap
A Beginners Explanation of Gamma Correction and Linear Workflow in 3D PDF
A Beginners Explanation of Gamma Correction and Linear Workflow in 3D Video
A Great Collection of Linear Workflow Knowledge and Links by Stu Maschwitz

What Is Your Current Workflow?
Let’s make this a conversation. Drop your workflow in the comments below. I would love to hear what you have learned about linear so far and how it has helped (or hurt) your renders. Do you use it? Do you like it? Let’s start talking and learning about this so we can stop being scared and start to use LW to our advantage.

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152  comments
152 Comments
  • You forgot to say what it is.

    You need a sentence that begins with “Linear Workflow is….” and then describe what it is.

    The heading on this page reads “what is linear workflow…” but we never find out. We just get a bunch of words that say other stuff.

  • Hey I think this really helped things make sense for me, especially because I didn’t realize how it applied to AE either.

    https://www.youtube.com/watch?v=jCVIqG-D2Vk

    In case this link is lost in an earlier comment I apologize. This thread has gotten quick deep on what appears to be a hot, and fascinating, topic.

  • Hi there –

    Has anyone run into problems with your alpha channels and multipass rendering when you work in Linear? I’ve noticed that the some of the special passes like diffusion or ambient occlusion flood the alpha channel now that I’ve switched to Linear in AE (16bit).

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