macOS
Universal · Metal
Download for macOS →
Install into
/Library/OFX/PluginsOpen-source display transform · OFX · Resolve · Fusion · Nuke
No more chalky highlights.
OpenDRT is an open-source picture formation transform, built to make an aesthetically pleasing picture out of raw camera image data. It gives image authors creative control over appearance, through a simple preset system and a deeper set of look-development modules.
Tone-scale curve, grey-scale ramp and RGB chips, the scopes that ship inside OpenDRT so you can see exactly how the transform reshapes your image.
What it is
OpenDRT replaces the last node in your node tree, the one reserved for the default CST that prepares your image for display. It assumes node-based color management as your grading pipeline, so the rest of your grade flows in scene-referred and lands on a calibrated screen.
Pick from 16 input gamuts, drive the look with Look and Tonescale presets, then optionally unlock the deeper look-development modules. It's a modern, neutral, filmic DRT with real per-hue control, and it costs nothing.
Download · OpenDRT
Three native builds: Metal on macOS, CUDA on Windows and Linux. Download, unzip into your OFX plugins folder, and restart your host. The effect appears under the Dec. 18 Studios group as OpenDRT.
Universal · Metal
/Library/OFX/Pluginsx86_64 · CUDA
C:\Program Files\Common Files\OFX\Pluginsx86_64 · CUDA
/usr/OFX/PluginsWant an older build or the source? Everything's on the Releases page. After unzip the layout is e.g. /Library/OFX/Plugins/OpenDRT.ofx.bundle/…
Getting started
OpenDRT is a standard OFX bundle. Drop it in your host's OFX plugins folder and restart. Or let the Tool Box Manager handle it with everything else.
Grab the macOS, Windows or Linux build from the Downloads above, then unzip the .zip.
macOS: /Library/OFX/Plugins · Windows: C:\Program Files\Common Files\OFX\Plugins · Linux: /usr/OFX/Plugins. The final layout is …/OFX/Plugins/OpenDRT.ofx.bundle/.
Relaunch Resolve, Fusion or Nuke so it picks up the new plugin, and make sure OFX is enabled.
Find OpenDRT under the Dec. 18 Studios OFX group and drop it on the last node in your tree. Set your input gamut and pick a preset to start.
The look-dev modules
Start with a preset, then reach into the modules when you want to go further. Each one targets a different axis of how color renders to display.
Scene-referred linear light → display-referred luminance.
Set contrast, rolloff and mid-grey placement: peak luminance for SDR or HDR, middle-grey in nits, toe and shoulder rolloff, contrast shaping above and below grey, and a shadow offset for density.
This is where exposure becomes a picture. Place mid-grey and shape the rolloff so highlights read clean, not chalky.
Color intensity relative to luminance.
A graceful purity compression that avoids harsh clipping and keeps perceptual smoothness as colors approach the edge of the gamut.
Saturated colors compress smoothly instead of slamming into a hard clip, so bright reds and blues stay believable.
Brightness of saturated colors.
Compensates clipping in narrow-band sources like LEDs, and adds soft glow and density variation to saturated highlights.
Practical lights and neon hold their shape and glow instead of blowing out to a flat blob.
Guide hue paths across luminance and purity.
Guide hue paths along the luminance and purity axes to address the Abney effect, with pleasing hue bends as tones move from dark to bright.
Hues stay where you expect as they brighten, no surprise shifts in skies, skin or saturated highlights.
In the original DCTL, full control meant the unwieldy "StickShift" build. In the OFX, manual and StickShift modes are combined in the UI and openly accessible, so you can tweak every preset directly.
Shape contrast in the upper range, above mid-grey.
Shape contrast in the shadows, below mid-grey.
Tune color intensity through the midtones.
Glow and density on saturated highlights.
Independent hue guidance on all six primaries.
Contrast driven by hue for richer separation.
Every module carries a persistent-value lock, so changing presets won't wipe the manual work you've already dialed in. Audition Look and Tonescale presets freely, your tweaks stay put.
Built-in scopes
OpenDRT ships its own overlays so you're never guessing how the DRT reshaped your image. Toggle them on while you work.
Shows how far off a linear line your RGB values are, a fast read on neutrality across the whole range.
Plots how tones shifted across 0–1, so you can see the contrast, rolloff and mid-grey placement at a glance.
Shows how individual hue vectors are affected, so you can check each primary's behavior through the transform.
Optional sandbox
A set of experimental modules ships alongside the core transform: filmic and projector simulation among them. Test them at your own discretion, they won't interfere with the core DRT, so your everyday grades stay rock-solid while you play.
It's free, always
OpenDRT is free and open-source, no subscription, no catch. If it earns a place in your pipeline and you'd like to chip in toward keeping it maintained, there's a spot for that.
License & attribution
This OpenDRT OFX incorporates and builds upon open-source components licensed under the GNU General Public License (GPL). All modifications and distributions are maintained in full compliance with the GPL. The complete source, including changes, is publicly available at github.com/Dec18studios/Open-DRT-OFX.
OpenDRT © Jed Smith. The OFX wrapper, CUDA and Metal backends, and build system are © Dec. 18 Studios, also released under GPL-3.0.