Film projects use digitized film images originating from a datacine conversion process. These are high-resolution scans of the film frames that preserve much of the film's resolution, colour depth, and grain.
Most film scans contain logarithmic data while video footage contains linear data. Logarithmic data allows for more subtlety in the lower luma ranges of an image, whereas linear data maps the luma range in equal intervals from black to white. In Lustre, you can work in either logarithmic or linear colour space.
When you need to convert and gamma correct shots with non-standard code value ranges or characteristic curves into the proper range for the selected colour space, you can use an image conversion Lookup Table (LUT) on input. You can use 1D LUTs and 3D LUTs as input LUTs.
A LUT is an ASCII file (Lustre supports the .lut file extension for 1D LUTs and the .3dl file extension for 3D LUTs) that describes specific pixel values used for image data conversion both on input and output. For example, you can use an input LUT to convert a 10-bit logarithmic film image to a 12-bit linear image when working in the linear colour space. You can then apply an inverse LUT on output to restore the 10-bit logarithmic data, ensuring that your resulting film prints match the original shots. See Setting Colour Space Options.
There are as many workflows when working with film and video footage as there are projects. In some cases, you may want to apply an input LUT to film to try to give it the look of different film stock. You may even apply an input LUT to video to try to give video clips a film look.
You can also apply monitor and Print LUTs to display images properly without affecting image data. See Monitor Calibration. If running the Windows version of Lustre, save print LUTs in the C:\Program Files\Autodesk\Lustre <version_number>\lut folder. If running the Linux version of Lustre, save print LUTs in the /usr/Autodesk/lustre_<version_number>/lut directory. Lustre provides industry-standard 3D LUTs which are located in C:\Program Files\Autodesk\Lustre Color <version_number> in the Windows version and/usr/discreet/Lustre_Color in the Linux version.
