mikaelsundell/dctl

A continuously updated collection of DCTLs (DaVinci Color Transform Language) designed to enhance and educate on workflows using ARRI LogC3 and Cineon in DaVinci Resolve. This collection offers a photographic and creative approach to color correction and grading from log digital and film negatives.

DCTL

Table of Contents

• DCTL
• Table of Contents
  • Introduction
  • Installation and utils
• DCTLs
  • Cineon color processing
    • MS-Cineon-Exposure.dctl
    • MS-Cineon-Invert.dctl
      • Cineon inversion
      • ACES scene-linear and calibration curves
    • MS-Cineon-Transform.dctl
  • LogC3 color processing
    • MS-LogC3-Print.dctl
    • MS-LogC3-Exposure.dctl
    • MS-LogC3-Transform.dctl
  • Utility DCTLs
    • MS-Stripify.dctl
    • MS-Saturation.dctl
  • DCTLs from other projects
    • Film Grain.dctl
    • Printer Lights.dctl
    • TetraInterp.dctl
    • TetraInterpHSV.dctl
  • Reference charts
  • References
  • Web Resources

Introduction

A continuously updated collection of DCTLs (DaVinci Color Transform Language) designed to enhance and educate on workflows using ARRI LogC3 and Cineon in DaVinci Resolve. These DCTLs offers a photographic and creative approach to color correction and grading from log digital and film negatives, emphasizing the artistic tweaking of the many variables involved rather than a strictly scientific method.

Installation and utils

To use these tools into your DaVinci Resolve setup, begin by cloning the git repository, which contains the DCTLs and headers.

Run python(.exe) run.py install in your terminal to copy the *.dctl and *.h files to the DaVinci Resolve LUT DCTL folder, ensuring they're accessible within your Resolve environment. The files can also be manually copied to /Library/Application Support/Blackmagic Design/DaVinci Resolve/LUT/DCTL on Mac and C:\ProgramData\Blackmagic Design\DaVinci Resolve\Support\LUT\DCTLon Windows.

For added convenience, the run.py script is provided, enabling easy access to various resources:

To open the DCTL readme documentation, use:

./run.py readme

For exploring DCTL examples, execute:

./run.py examples

To access the DaVinci Resolve log file and initiate a trace, input:

./run.py install

**To install .dctl and .h into DCTL directory:

./run.py log

To make a snapshot of hte DaVinvi Resolve DCTL folder, input:

./run.py snapshot

DCTLs

Cineon color processing

MS-Cineon-Exposure.dctl

Cineon exposure from photographic stops, incorporating a zone based false color to aid in achieving correct exposure levels.

• https://github.com/mikaelsundell/dctl/blob/master/MS-Cineon-Exposure.dctl

MS-Cineon-Invert.dctl

Cineon inversion

Cineon negative inversion with precise control over the dmin ratio based inversion process using adjustable parameters such as density, bit depth, offset, and density scale. You can specify dmin base values manually as floating-point numbers (obtained from tools like Pixel Analyzer in Nuke or similar software) or sample them using a rectangular sampler from the border or other dmin base areas.

ACES scene-linear and calibration curves

To account for the variations of film stock and the use of ECN-2 chemicals, developer time and temperature, camera and lightbox settings - calibration curves are applied to match ideal cineon code values. In this example, photoscanning was used along with the rawtoaces tool to convert the Camera RAW CR2 file to scene-linear ACES, starting with as much information as possible. However, because the science is not exact, manual tweaking using density scaling and calibration curves is needed depending on the setup.

Color calibration curves and macbeth charts at different exposures for adjustments.

DCTL script

• https://github.com/mikaelsundell/dctl/blob/master/MS-Cineon-Invert.dctl

rawtoaces project

• https://github.com/AcademySoftwareFoundation/rawtoaces

MS-Cineon-Transform.dctl

Cineon conversion to and from linear.

• https://github.com/mikaelsundell/dctl/blob/master/MS-Cineon-Transform.dctl

LogC3 color processing

MS-LogC3-Print.dctl

Made for print emulation, this DCTL applies DaVinci Resolve's built-in film looks to ARRI LogC3 and Cineon footage with adjustable controls for contrast and color strength.

• https://github.com/mikaelsundell/dctl/blob/master/MS-LogC3-Print.dctl

MS-LogC3-Exposure.dctl

LogC3 exposure from photographic stops, incorporating a zone based false color to aid in achieving correct exposure levels.

• https://github.com/mikaelsundell/dctl/blob/master/MS-LogC3-Exposure.dctl

MS-LogC3-Transform.dctl

LogC3 conversion to and from linear.

• https://github.com/mikaelsundell/dctl/blob/master/MS-LogC3-Transform.dctl

Utility DCTLs

MS-Stripify.dctl

Matrix adjustments, this DCTL simplifies the color palette by pushing colors into a warm and cool strip.

• https://github.com/mikaelsundell/dctl/blob/master/MS-Stripify.dctl

MS-Saturation.dctl

HSV-based adjustments, this DCTL provides a tool for fine-tuning saturation using saturation in HSV.

• https://github.com/mikaelsundell/dctl/blob/master/MS-Saturation.dctl

DCTLs from other projects

Film Grain.dctl

• https://github.com/thatcherfreeman/utility-dctls/blob/main/Effects/Film%20Grain.dctl

Printer Lights.dctl

• https://github.com/thatcherfreeman/utility-dctls/blob/main/Utilities/Printer%20Lights.dctl

TetraInterp.dctl

• https://github.com/hotgluebanjo/TetraInterp-DCTL/blob/master/TetraInterp.dctl

TetraInterpHSV.dctl

• https://github.com/hotgluebanjo/TetraInterp-DCTL/blob/master/TetraInterpHSV.dctl

Reference charts

• ACES Macbeth 50D 5203 EXR exr from rawtoaces

• Download: macbeth_50D_5203.exr

ARRI LogC3 10-bit DPX

• Download: logctool_LogC3_DCI_2K.dpx

Cineon 10-bit DPX

• Download: logctool_LogC3_to_Cineon_DCI_2K.dpx

Logctool project:

• https://github.com/mikaelsundell/logctool

References

ARRI Companion to DI

• https://dicomp.arri.de/digital/digital_systems/DIcompanion/index.html

Blend modes:

• https://skia.googlesource.com/skia/+/70e432e72745/gm/hsl.cpp

Cineon conversion in RV:

• https://github.com/AcademySoftwareFoundation/OpenRV/blob/main/src/plugins/rv-packages/additional_nodes/LinearToCineonLog.glsl
• https://github.com/AcademySoftwareFoundation/OpenRV/blob/main/src/plugins/rv-packages/additional_nodes/CineonLogToLinear.glsl

Grayscale legacy luma:

• https://en.wikipedia.org/wiki/Grayscale

Web Resources

• GitHub page: https://github.com/mikaelsundell/dctl
• Issues https://github.com/mikaelsundell/dctl/issues

dctl's Issues

the dctls dont work in resolve on a windows pc

downloaded the dctls for the cineon inverse dctl to experiment with film scans, but the dctl doesn't work, i have the studio version of resolve 18.6 at the moment on a quite capable windows pc.

Error in MS-Utils.h

Line 137:

return max(rgb, 0.0f);;

AFAIK you can't compare a float3 with a float.

use sth. like this :

DEVICE float3 adjust_display(float3 rgb)
{
rgb.x = _fmaxf(rgb.x, 0.0f);
rgb.y = _fmaxf(rgb.y, 0.0f);
rgb.z = _fmaxf(rgb.z, 0.0f);

return rgb;;

}