Autodesk Combustion 4

A Swiss Army Knife of Pro VFX Tools

By Peter Plantec

September 1, 2005    Source: Studio Monthly

The more I work with Combustion 4, the harder it is to review. It just does so many things, so well, and I have such little space. In simple terms, Combustion 4 is Autodesk’s way of bringing you top drawer, affordable VFX compositing technology based on its Discreet line of high-end systems. Autodesk refers to Combustion 4 as its "all-in-one professional compositing application." And the company doesn’t just mean 2D compositing, but 3D as well.

Workflow

Combustion 4 provides well-researched, efficient workflows and a uniquely flexible interface that, once you learn how to use it, will provide the creative tools and processes you need to create just about anything you can think of in moving images. The biggest workflow time factor is slow re-caching in RAM every time you make a change. However, with DI (Digital Intermediate) processing and Panavision’s Genesis digital camera system galloping onto the scene, Combustion 4’s enormous tool set is a treasure. Thank heaven for the excellent schematic view, which helps me figure out how in hell I ended up with what I’ve got at any given moment. It gives me immediate access to any point in the tree for adjustments. However, because of all this depth, and clever interfacing, expect a serious learning curve.

Architecture

Flexibility is the word. Everything seems to be pluggable into everything else, anywhere on the timeline.

The system architecture is resolution independent in any format from Flash to HD and feature film. You can mix and match different image resolutions and color bit depths as well. RAM caching speeds play back so you can work interactively with multiple processes at or near real time. And I’m pretty sure Combustion uses GPU power, if you’ve got it, to animate real-time particle displays as you work with them interactively.

Interoperability

Few reviews say much about interoperability, but it’s a key factor here. Combustion 4 can act like an extension of 3ds Max. It imports target cameras as.ase files and Max’s RPF/RLA files complete with extended channel information for controlling various post operations. This includes stuff like depth and mask information. With it you can re-light a scene after the fact and do 3D depth compositing. In fact, you can even use imbedded RPF/RLA camera information to control Combustion’s camera movement and orientation for 3D compositing. 3ds Max and Combustion are so tightly integrated you can actually paint directly into Max viewports using Combustion paint tools.

Combustion also hooks directly into the Discreet systems’ high-end pipeline flawlessly exchanging masks, along with keyer and color corrector and tracker data, plus film tools like grain and color LUTs (Look Up Tables) with Discreet Lustre, Discreet Inferno, Discreet Flame, Discreet Flint, Discreet Fire and Discreet Smoke. Smooth.

Adobe Photoshop works well with Combustion 4. In fact, most of those millions of Photoshop filters plug right in and Combustion reformats them to work seamlessly within your work environment, adding key-frameable value changes to boot.

And talk about I/O support! With FireWire DV controls, all popular image and animation formats, and 10-bit Cineon formats (paint/rotoscope directly in 10-bit without conversion,) and with OpenEXR export, forget external conversion programs. Of course NTSC/PAL and HDTV formats are supported with field rendering and 3:2 pull down interpolation with automatic phase detection-handy. You can import Photoshop CS2's .psd layer files with individual layers conveniently separated for compositing. Import and edit Adobe Illustrator files with gradients and layers, as resolution-independent components for your flash animations. It just goes on and on.

Operators

Operators are your plug-in tools. You work in Combustion by creating image/time manipulation processes by applying operators to a single layer, a composite anywhere in a process branch. To do this you access the operators you want from professional color correction to point tracking and particles, to diamond keying. Many operators can be used to control others. For example, an expression operator might control the path of a tracked particle emitter spinning in a helix around an actor's head, as a tracked mask hides the dripping sparkles as they fly "behind" his head. It also allows you to add the Time Warp operator to make it look like he's walking through water. There is an operator for just about anything you need to do and they are quality tools. What I mean by that is, the tracker is taken directly from Discreet Flame and the color correction system is from Discreet Lustre.

Check the side bar for a representative list of operators. You access these through a flexible, customizable interface. Set it up the way you work best. The schematic access interface shows how all the operators are interconnected and gives you direct access to relevant parameters. Everything can be key-framed as well. Complex custom processes can be encapsulated and saved for future projects. It's a lot like Photoshop actions. I expect to see web sites with downloadable Combustion capsules of all descriptions.

The fantastic context sensitive work areas help enormously because you only see the settings you need. It's all very complicated, but Discreet/Autodesk has done an amazing job of making it workable.

Summary

I think the amazing number of excellent, well-implemented tools and the fine performance of Combustion 4 have left us all feeling like we're getting way more than our money's worth. You absolutely must use a powerful computer with plenty of RAM, however. The particle effects alone are worth the price of admission, or the color correction, or any one of the keyers. In fact, each only represents about two percent of the entire package.

However, that steep learning curve I mentioned before is serious, and is exacerbated by the enormous depth of layering and interdependencies you can develop as you work. When you get into this thing you'll find yourself creating amazingly complex processes controlled by expressions, tracking, key frames and previous operations. I highly recommend you take time to truly learn Combustion in depth. You will not regret one second of your effort. The one very serious and totally thorough training course I must recommend is the Combustion 4 Training DVD's from TSP (The Street Productions, www.thestreetproductions.com). Ken LaRue and friends have done a masterful job of laying out virtually every aspect of Combustion in more than 20 hours of instruction on five DVDs, with source material included. The series is an absolute bargain at around $300.

With release 4, Autodesk has truly given us a wonderful, professional gift.