The RIGHT way to setup the HSL Qualifier... | DaVinci Resolve 19 - Colour Grading Tutorial
Today, I want to share a method I use for working with the HSL (Hue, Saturation, Luminance) qualifier in DaVinci Resolve.
This approach is part of my Cinescope Powergrade and general workflow, even if I’m grading from scratch. It allows you to access a broader range of colors when using the HSL qualifier without placing it too late in the workflow, which can cause issues if adjustments need to be made.
What is the HSL Qualifier?
For those unfamiliar, the HSL qualifier is a tool in DaVinci Resolve that lets you manually select specified Hue, Saturation and Luminance areas in an image, determined by these values. This selection isolates the chosen values so that any adjustments made only affect those areas.
When selecting a pixel, for example, a red area on a colour card, the HSL qualifier highlights that color and nearby hues. Using tools like "Shift H," you can view the selection and refine it to be more precise. However, the effectiveness of your selection depends on how and where the HSL is placed within your node tree.
Challenges with Placing the HSL Qualifier
A common question is: Where should the HSL qualifier node go in the workflow?
Before Primaries (After Colour Space Transform):
This approach places the HSL qualifier after the input colour space transform (CST), but before your primary adjustments - like exposure, contrast, or colour balance.
While this ensures your selection isn't affected by primary adjustments, it may lack sufficient colour data as you are working in a LOG space. The colours in this stage are often desaturated and low contrast, making fine selections difficult.
2. After Primaries:
Adding the HSL qualifier after your primary adjustments gives access to more color information. However, it still might not provide the precision required for refined selections. It is also susceptible to changing if you adjust any of your primary nodes.
3. At the End (Post-Rec.709 Transform):
Placing the HSL qualifier at the end of the workflow offers the most detailed colour information, as the image is fully processed. Selections are much more precise, allowing you to fine-tune adjustments.
The downside? Any subsequent adjustments to primary nodes will disrupt the HSL selection, forcing you to reselect and refine the colours — a frustrating and time -consuming process.
The Solution: Using Multiple Inputs
The goal is to maintain the colour richness of a post-Rec.709 node, while keeping the flexibility of pre-primary adjustments. This can be achieved by creating a custom node structure using multiple inputs:
Set Up the Node Tree:
Create three main nodes:
Input Transform Node (Rec.709): Transforms the image into Rec.709 colour space.
Qualifier Node: Handles the HSL selection.
Adjustments Node: Apply adjustments to your HSL selection.
Configure Node Connections:
Connect the RGB output of the input transform node to both the qualifier and adjustments nodes.
Link the alpha output of the qualifier node to the adjustments node.
Finally, route the adjustments node to the output.
How It Works:
The HSL qualifier now uses the full Rec.709 colour space, allowing for precise selections.
Adjustments made in the primary nodes won’t affect the HSL selection because the qualifier operates independently from the primary workflow.
Simplified Node Diagram
To make this setup easier to replicate, here’s a simplified version of the node tree:
Final Notes: This method isn’t limited to Rec.709 or a specific gamma setting; it’s versatile and adaptable to various workflows. Whether you're working in log, Rec.709, or another colour space, the same principles apply.
Thank you for watching! If you found this helpful, please like the video, subscribe for more tutorials, and drop any questions in the comments below. Happy colour grading!
