How to Achieve a Natural Color Grade in DaVinci Resolve Using a Node Tree

Jeff Lathrop

Summary:

This video demonstrates how to create a natural and well-balanced color grade for an interview scene in DaVinci Resolve, starting from a Rec. 709 image.

• The process begins with adjusting exposure using the highlights slider and setting the contrast and pivot point for middle gray.
• White balance is then fine-tuned with the gain wheel in linear gamma, followed by strategic use of power windows to shape the image and direct viewer focus.
• A shadow node is used to introduce cool tones, contrasting with warmer areas.
• The instructor emphasizes checking scopes to avoid crushed blacks and uses a soft clip node to lift the low end of the exposure.
• A Rec. 709 offset node adjusts overall luminance without altering contrast ratios, and a Film Look Creator (specifically Rochester preset) is applied to subtly desaturate reds and add a filmic quality.
• The workflow often involves working out of order, making adjustments as needed, and concludes with a final contrast punch using curves.

Introduction to Natural Color Grading [0:00]

The video demonstrates a practical color grading breakdown for an interview scene shot with natural light, aiming for a natural, well-balanced image without excessive complication. The instructor uses his favorite node tree, previously detailed in another video.

Working Out of Order [1:25]

The grading process doesn't strictly follow a linear node order; adjustments are made as needed, often jumping between nodes to achieve the desired look. This flexibility is a common practice for experienced colorists.

Project Settings [2:46]

Before starting the grade, the project settings are configured as follows:

• Color Management: DaVinci YRGB.
• Timeline Color Space: DaVinci Wide Gamut and DaVinci Intermediate.
• Output Color Space: Rec. 709 Gamma 2.4.
• Color Space Transform Input: Blackmagic BRAW to DaVinci Wide Gamut.
• Color Space Transform Output: DaVinci Wide Gamut to Rec. 709 with DaVinci Tone Mapping (Custom Max Input 10,000, but often experimented with or disabled to manage highlights manually).

Starting from Scratch (Exposure and Contrast) [3:35]

The initial step involves adjusting the general exposure to bring the image into a workable range, making it easier to see and develop the desired look.

• Highlight Adjustment: The highlight slider is used to lower highlights, often by -100, to soften the top edge of the exposure and prevent clipping.
• Contrast and Pivot:
  • The pivot point is set to .336, which is middle gray for DaVinci Wide Gamut, ensuring that contrast adjustments pivot around true middle gray.
  • Contrast is gradually increased (e.g., to 1.15) while monitoring the waveform to ensure highlights are around the 90-95 level and blacks are not crushed.
  • Proper exposure helps reveal natural saturation levels.

White Balance [7:10]

White balance is fine-tuned to ensure color accuracy:

• Gamma Setting: The gamma is changed to linear.
• Gain Wheel Adjustment: The gain wheel is used to slightly cool the image, making a subtle adjustment that is barely noticeable by eye but contributes to overall balance.
• Luma Mix Consideration: While adjusting white balance in linear gamma, it's recommended to drop the Luma Mix to zero to only affect white balance, although in practice, the speaker rarely notices a significant difference between 0 and 100.

Power Windows (Shaping the Image) [8:07]

Power windows are crucial for reshaping the image and directing viewer focus:

• Brightening the Subject: A large, feathered power window is used to slightly brighten the subject's exposure (+.01), especially on the side where the natural light originates.
• Creating a Vignette: An "outside" node with a power window is used to create a vignette, dropping the gamma by -.03 to darken the edges and draw focus to the center.
• Addressing Distracting Areas:
  • A linear gradient power window is applied to the subject's left side to darken it, reducing distraction from bright areas and improving the lighting ratio. This window also adds a subtle warmth.
  • Another linear gradient power window darkens a distracting bright mirror frame on the subject's right side.

Shadow Node (Color Contrast) [11:00]

After initial adjustments, if the image appears too warm or red, the shadow node is revisited:

• Cooling the Shadows: The shadow wheel is adjusted towards the lower right (blue) to introduce coolness into the shadows, particularly noticeable on the subject's shirt. This creates a pleasing color contrast with warmer elements in the scene.

No Saturation! [11:37]

For this particular grade, no additional saturation adjustments are made using the dedicated saturation nodes, as the desired saturation is achieved through proper exposure and contrast.

Check the Scopes (Avoiding Crushed Blacks) [12:12]

Regularly checking the waveform scope is vital to ensure proper luminance levels:

• Reference Levels: Reference levels for the waveform are set to 40 (low end) and 950 (high end) to prevent crushed blacks or clipped highlights, as eyes can be deceiving.

Soft Clip (Refining Black Levels) [12:50]

If the waveform indicates crushed blacks despite visual appearance, a soft clip node is used:

• Low Soft Slider: The low soft slider in the custom curves is adjusted to gently raise the tail end of the exposure, lifting the black levels slightly without drastically altering contrast.

Rec 709 Offset (Overall Luminance Adjustment) [13:25]

After establishing contrast and black levels, the Rec. 709 offset can be used for a global luminance adjustment:

• Raising Overall Luminance: The offset wheel in the Rec. 709 output transform is used to subtly lift the entire waveform, bringing the black levels up to the desired reference point (e.g., 40) without disturbing the established contrast ratios or other delicate adjustments.

Film Look Creator (Subtractive Saturation and Style) [14:23]

The Film Look Creator is utilized as a final touch for subtle stylistic adjustments:

• Subtractive Saturation: The main purpose is often for its built-in subtractive saturation, which helps manage overly vibrant colors, particularly distracting reds. The "Rochester" preset is often favored for its treatment of reds.
• Fine-Tuning: The default contrast (often too punchy) is reduced, and the film look blend and color blend are adjusted to achieve a subtle effect rather than a full, intense look. No split toning, vignette, or bloom is added to maintain a natural appearance.

Working Backwards [17:20]

The instructor reiterates the non-linear workflow, starting with exposure, then moving to white balance, power windows for shaping, shadow nodes for color, soft clip, offset, and finally the film look creator. While a linear approach is also valid, this "working backwards" method allows for iterative refinement.

Lum Mix Note [19:08]

Revisiting the Luma Mix setting when performing white balance in linear gamma, the speaker notes that while some recommend setting it to zero to isolate white balance adjustments from exposure, he rarely observes a significant visual difference and finds that allowing minor exposure shifts can sometimes lead to a more natural result.

Recap [20:45]

A quick recap of the entire process highlights the key steps:

1. Exposure: Drop highlights to a reasonable level.
2. Vignette: Shape the image by brightening the talent and darkening the edges with power windows.
3. Gradients: Use additional linear gradients to manage distracting bright or dark areas, ensuring focus on the talent.
4. Warmth/Coolness: Warm up desired areas and introduce blue tint into shadows using the shadow node for color contrast.
5. Black Levels: Use soft clip to slightly raise black levels and Rec. 709 offset to adjust overall luminance.
6. Film Look: Apply Film Look Creator for subtle subtractive saturation and a refined aesthetic.
7. Final Contrast: Add a last punch of contrast using curves if needed.

Contrast Curves [22:19]

A useful "contrast hack" involves using curves:

• Locking Exposure: Use the dropper tool to click on a key area (e.g., talent's face) on the image to lock that specific exposure level on the curve.
• Adjusting Contrast: Then, manipulate the editable splines of the curve to adjust contrast around the locked point without changing the exposure of the chosen area.