Like all the teams in this film it’s made up entirely of volunteers like yourself from all over the world. On behalf of the Production team thank you for being a part of our journey and I hope we can make your stay an enjoyable one.


One this page you’ll find lots of different bits of information. We have artists of many different skill levels helping us so hopefully there is something here for everyone.


The first is the most important. We run a private Skype channel called the Troll Bridge Water Cooler. If you have a Skype account I strongly encourage you to sign up:


The water cooler is a great place to meet other artists working on Troll Bridge and talk about other movies, books, games, sports pretty much anything you like. It’s also a great help resource as well. If you have a particular problem with a script and you are not in an Australian timezone, then there is a good chance that another artist on the Water Cooler may be able to help. Having a fun, supportive and encouraging environment is very important to us, so I hope to see you there.

General Comp Notes

The Composite team has two key objectives when working on a shot.

  1. Integrate all the elements, including matching black/white levels, blending, extraction & layering and applying selective lighting if required

  2. Make the shot look as good as it can! Many thousands of person hours have gone into the live action and digital elements to get them to this point. We want every shot to look as good as it can, so getting most out of the material available is very important.

Lens distortion grids can be found here:


Reference plates

We have a growing number of reference plates in EXR/Linear format at:

These plates can provide both colour and style guides for most key elements, so be sure to check them out.



We frequently apply a “studio lut” to live action footage shot on the bridge set. Due difference between the Mac and PC there are two versions of this file depending on what platform you use:


When handed over to the comp team, shots on the bridge will already have the live action plate alpha created in a “roto” script. In many cases these roto’s and keys will need further refinement by the Composite team. When starting a new shot the first thing an artist should look at is the roto, with particular attention to soft edges like Cohen’s beard and hair. Getting the correct key in Comp is the most important part of making the shot ‘look right’.

Assembly Comp’s

All shots will be delivered to Comp via an Assembly Comp script.  This assembly is designed to give the Director and other department heads a first-look at a shot so they can see if there are any problems that require more work before Comp begins. They are also a useful starting point for Comp to begin working with. Assemblies will NEVER include shot specific lighting, re-colouring or other works. The individual Compositors will need to review the assembly script and make whatever adjustments are required for their shot.

Lens Distortion

Lens distortion can be a problem on some shots, particularly those with a tracked objects like the magical sword or talking horse. In all cases Comp Artists will need to review the distortion requirement for their shot in particular. In some cases the assembly comp will include an enabled distort/undistort workflow but this should always be reviewed carefully. See the “Lens Distortion Tutorial” for more information.

Comp Assets


By clicking on that link you will be directed to the DropBox folder. Typically you will wanted to download the following folders:

  • Audio

  • Comp

  • Matte (if one exists

  • Plates\Plate_EXR

  • The most recent version of shot specific assets(eg Mica, Sword, Horse)

(when in doubt review the asset loaders in the assembly script or ask the Producer/Comp Supervisor for assistance)

*A note about downloading from DropBox
DropBox has difficult downloading asset collections greater than 2gb in size. Our plate and render folders will occasionally be bigger than this.  If you encounter difficulties downloading a folder, try selecting smaller groups of files. Typically blocks of around 40 frames at a time is fine for most assets.


If problems persist, contact the Producer for additional support.

Additional Comp Assets

Troll Bridge has a large library of cloud, snow, breath debris particle and other elements that can be used in comps.

Cloud Library (photos, 2.7GB):

Large Elements (footage, 48 GB, pick-and-choose):

An important note about intermediate assets or assets from your personal library.

The final render of each Composite will be done by the Troll Bridge Production team in Melbourne, Australia. For this reason it’s important that we can open you script and successfully render it. If your script uses intermediate or ‘pre-comp’ed’ elements, please make sure to include and clearly identify the write nodes in the scripts you post for review. This way we can re-generate your pre-render or intermediate element at our end. Also we try to discourage the use of elements from an artist’s personal library as we won’t be able to get the required clearances easily. If you have a particular asset you’d like to use, speak to the Comp Supervisor or Producer. We have a large library of generic elements already available [see below]

Shot Assets

The assets for a shot are contained in a specific “Shot Folder” on DropBox. You can locate the link for any one, by going to the specific shot page on Shotgun:

Other Helpful Resources

Folder Structure

Depth Control


Good Roto Tutorial

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