Color Matching References in DaVinci Resolve
Show Viewer Channels
The color page of DaVinci Resolve has a hidden superpower to match colors from one shot to another or one reference still image. No, it’s not the scopes, although the scopes are an excellent objective approach to evaluating an image for color correction and grading. And no, it’s not that you can send a clean feed out to an external calibrated display set to a particular standard. It's a simple feature that allows you to view the individual color channels that make up the image one at a time—the RGB channel viewer.
The “show viewer channels” option is available in the top right three-dot menu of the color page viewer. Choose G, and you’ll see the greyscale representation of light (intensity) pixel values for the green channel. R for red and B for Blue. However, there is no default keyboard shortcut to use these viewers quickly, so I suggest setting up a special keyboard shortcut to view individual channels on the color page.
Under the DaVinci Resolve keyboard customization menu, search for viewer channels. I like to set this to the first letter of the color (r for red, b for blue, g for green, and then c for color). This also mimics the viewers on the Fusion page, so it’s easy to remember.
But why does viewing an individual channel help us match one color to another? Well, it’s because God created our eyes in a way that is more sensitive to brightness and color differences. We can easily distinguish whether we need to bring the intensity (value) higher or lower when we remove the color from a split screen comparison. So, the next step is to pull a reference and overlay it with an image wipe.
Grab a Still
To create an image wipe in DaVinci Resolve, grab a reference and a still first. An easy way to do this is to right-click on the color page viewer and click to grab a still. This could be a final graded image or a JPEG or PNG reference pulled from the internet. It just has to have some precise color information you want to match.
Once the still is in the stills gallery, you can double-click it to open the Resolve reference image wipe feature. This allows the still to be overlayed on top of the currently selected clip in the timeline for comparison. You can drag the vertical split wipe to an area that you’d like to match up and work toward blending on all three individual channels, one by one. If you don’t see an area that lines up perfectly, you can change the scale or position of the still wipe using the scaling pallete under the reference sizing tab.
Printer Light Hotkeys
The printer light keys, or offset controls of the primary lift, gamma, gain pallete of the color page might be the oldest tool in a colorist kit - but man, are they powerful! They add or subtract to that specific RGB color intensity. That’s all they do. And that is a good thing because it keeps the original photography intact with all the contrast in the actual scene - making it look natural.
Printer light keys can be operated with the number pad of a traditional keyboard—that block of numbers on the far right of the larger keyboards. If you edit or color - you need a full-size keyboard! The number pad is ideal for editing, entering timecode values, and moving clips around on a timeline.
After enabling them under the Color dropdown menu, learning to use the printer light hotkeys is easy. 7-8-9 is your R-G-B. If you need to reduce the R-G-B, lower your fingers to 4-5-6 to lower the value. It is worth noting that these controls work best on Log encoded footage rather than a 709 image with expanded contrast and saturation, but to match one color to another with a power window - these work great for this function, too. However, if it were Log, I would only use printer lights for white balancing an entire image. For a 709 image, using Gain with the node gamma set to linear and the Lum Mix turned to zero is better.
Finally, to match the color without viewing the full-color image, tap G to start viewing the green channel. We start with green because it has the most luminance in the image. Green is also the most sensitive to our eye, so we can usually tell if something is not looking right here. With the image wipe turned on and looking at the green channel, tap 8 or 5 to make the image adjusted to match the reference so you can’t see the image wipe line between the split wipe.
Next, load up the Red channel viewer with R and use the 7 and 4 number keys to match those. Load the blue channel viewer with B and use the 9 and 6 number keys. Once there is no line visible on all 3 channels, you should have a pretty close match. Hit C for color, and you can move on to isolating the correction with a mask.
DaVinci Resolve can mask in many ways. Power window shapes, qualifier keys, and even magic masks use motion vector data to extract subjects. Different shots require different masking methods, but the gist is to mask out the corrected color so the offset change does not affect the rest of the graded image.
