After all the basic editing, sound design, seamless transitions, and video text effects comes color. Color correction is one of the last — if not the last — steps in the post-production workflow. If your final video appears flat, dull, or like it was shot from an old handheld camcorder, you’re missing this vital step!
Professional color correctors, or colorists, spend a good deal of time learning color theory, training with color software tools, and practicing on different footage. But we’ll try to tackle the absolute basics in this brief color correction crash course.
Overview: What is color correction?
Color correction is the process of adjusting white balance, fixing exposure, balancing white and black values, and tweaking contrast and saturation. When dropping your raw footage into your editing software, you’ll notice the video color doesn’t look quite like it’s supposed to — color correction fixes that.
The goal is to recreate the natural, even look of the footage and establish consistency across all shots. It’s a huge part of the post-production workflow and, nowadays, can be fully handled in most nonlinear editing software.
Color correction vs. color grading: What’s the difference?
As mentioned, color correction is balancing and naturalizing the image and it always precedes color grading. Color grading comes after color correction; it is a way of creating a mood or look with the image. You can think of color correction as fixing the image before the color grade adds a creative and artistic touch to the video.
How to color correct your videos
Color correction workflow preference can vary, but there are some consistent steps. Below is a common sequence of color correction steps. This workflow was done with Lumetri Color in Premiere Pro, but some of the terminology and general guidelines are helpful within Avid Media Composer, Final Cut Pro, and DaVinci Resolve.
Most color correction will be done in the basic correction panel of Lumetri Color in Premiere Pro. The Curves, Color Wheels, and HSL Secondary panels all have valuable color correction tools but are more difficult to use and easier to mess up. So, we’ll focus on basic correction for this color editing guide.
1. Set up your interface and scopes
Before you even get going with correcting your footage, set up your workspace to cater to the color workflow. In Premiere Pro, I like to make the following changes to the default Color workspace and available scopes:
- Add a reference monitor next to the source monitor for shot matching.
- Expand the timeline over to cover the audio levels meter since sound isn’t needed for color correction.
- Under the Lumetri Scopes panel, I use the Vectorscope YUV, Parade (RBG), and Waveform (Luma), but explore and research all the scopes to fit your needs.
- The Lumetri Scopes panel is in the source monitor, and the wrench icon at the bottom of the panel is where you can adjust scopes.
- Also under the wrench icon, select the colorspace you are using: Rec. 601 is standard definition, Rec. 709 is high definition, and Rec. 2020 is HDR and 4K footage.
- Next to the wrench icon, uncheck the Clamp Signal box. If it is checked, your scopes won’t show signal above 100 IRE, or below 0 IRE.
- Lastly, you’ll most likely be using 8-bit color display, but check your camera and footage to confirm.
In terms of scopes, the Parade (RGB) is used to fix white balance and exposure and has three different graphs for red, green, and blue. In 8-bit, the values on the right of the graph range from 0-255, and the values on the left range from 0-100. The top of the graph is the brightest values and the bottom of the graph is the darkest values.
The Waveform (Luma) is used to correct exposure and ranges from 0-100 IRE with 0 being absolute black and 100 absolute white. Both the Waveform and Parade scope correspond to the image from left to right.
Scopes are never wrong. If your image visually looks off, but appears balanced in the scopes, trust the scopes. Factors like room lighting, screen calibration, and even the color of the walls can alter the perception of color on your monitor. Fun note: Professional colorists work in a neutral grey room with specific lighting so as to not throw off the color.
2. Pick a “hero” shot
One aim of color correction is to create a consistent correction across all the shots and footage. It would be distracting if the footage from one camera angle had a different color temperature than the footage from another camera angle.
To create consistency, pick a hero shot to correct first, and then use it as a reference for the rest of the footage. The hero shot should be a middle-of-the-pack image in terms of video coloring and exposure. Picking an outlier shot with way different exposure or colors than the rest of the footage won’t be as effective.
Once the hero shot is corrected using the following steps, you’ll use Premiere Pro’s reference monitor to match the correction to other shots. Explore the Vertical Split, Horizontal Split, Side by Side, and Shot or Frame Comparison icons within the program monitor to learn how to set up shot matching. All these functions can be accessed by turning on Comparison View in the program monitor.
3. Input LUTs
First up in basic correction, you’ll have the option of dropping an input look-up table (LUT) onto imported footage. Input LUTs are used to save time and get your footage to a good starting point for further correction.
Sometimes referred to as speed LUTs, input LUTs interpret Log footage from specific cameras and apply a basic correction for you. For example, if you shot your footage on a RED camera, you would use an input LUT specific to that camera and color profile in post-production. Log footage is preferred because it retains a ton of color information and tonal range.
4. WB Selector
Next, you have the white balance subsection within the basic correction panel. White balance is adjusting the temperature of the white in your video to create a true white. If the color temperature of white is off, then every other color will appear off.
The first tool you can use to correct the white balance is the WB Selector eyedropper. If there’s something in your shot that is close to a true white — a dress, tabletop, sheet of paper — you can use it as a reference point.
Clicking a white object with the WB Selector will automatically adjust the white balance settings to a usable spot. Some filmmakers will place a white card, or even use the slate from the beginning of each shot as a reference point in post-production correcting. The white balance may still need some adjusting after using the WB Selector.
5. Temperature and tint sliders
The temperature and tint sliders can be used after the WB selector, or as a starting point. The sliders are straightforward and easy to use:
- If the image appears too blue, or cool, move the temperature slider to the right toward the orange portion.
- If the image appears too orange, or warm, move the temperature slider to the left toward the blue portion.
- If the image has a green tint, move the tint slider to the right toward the magenta.
- If the image has a magenta tint, move the tint slider to the left toward the green.
You can get a good sense of how balanced your image is just by looking at it, but the scopes are perfectly accurate. For white balance, the Parade (RGB) will tell exactly how balanced your image is in primary colors. Side note: Photo and video use the additive RGB colorspace, in which red, green, and blue are primary colors.
In a balanced image, the red, green, and blue graphs will match. More specifically, the top portion representing highlights and the bottom portion representing shadows will match — the midtones will vary. So the goal is to match the graphs.
Quick video editing tip: Double-click to reset sliders, curves, or wheels to their default settings.
6. Balancing tone
In the tones subsection, start with exposure. Using the Waveform (Luma) as a guide, slide the exposure until the reading is in a safe starting point between 0-100 IRE. Next, adjust the contrast to a more appealing level. Then, move onto the other tones using these parameters:
- Blacks target the darkest parts of the image around 0-20 IRE.
- Shadows are slightly lighter than the black values around 20-50 IRE.
- The Highlights will affect values from around 50-80 IRE.
- The Whites slider will target the brightest spots between 80-100 IRE.
Start with the black and white values and then move to shadows and highlights! When properly exposed and balanced, the scopes should be evenly synced and the image should appear more natural.
Balancing the tones and gamma values — shadows and highlights — can be tricky. It will take practice to get comfortable with this step. Just keep moving the sliders around and notice the effect of each.
Saturation is last on the to-do list in basic correction. After the image is balanced and properly exposed, use the saturation slider to get closer to a natural look. Adding saturation gives the perception of underexposing the image while decreasing saturation gives the perception of overexposure. Also, if the image is properly exposed but lacks pop, saturation can be added to increase vividness without affecting the exposure.
Using masks for basic color correction
It can be difficult to balance the Parade (RGB) with all the other information coming from the image. To get a clearer reading, mask out a white region or black region of the video and use it to match the graphs.
Navigate to the Effects Control Panel and use the mask tools under Opacity to section off a small portion of white or black. Once masked, use the Parade (RGB) to line up the visible signal across the red, green, and blue. Again, if you mask out white, you’ll be focused on the top of the graph, and if you mask out black, you’ll be focused on the bottom of the graph.
Masking and motion tracking is also used in correcting exposure, especially skin tones. If you’re having difficulty getting a natural look to skin tones, mask out that region and refer to the Ansel Adams Exposure Chart for the correct IRE values for different skin types. The chart is also helpful for exposure in general. For example, tan skin will hover around 50 IRE, and pale skin will hover around 70 IRE.
Moving on to secondary correction
It may be hard to believe, but all of the above is just a quick rundown of solely basic color correction. Secondary color correction lends more useful and precise tools to accurately and efficiently correct footage.
Once you’re comfortable with the Basic Correction panel in Lumetri Color, survey the Curves, Color Wheels, and HSL Secondary panels. They are definitely more complicated than basic correction tools but offer a lot of functionality and are cool to mess around with. I’ll cover secondary tools in a later tutorial, but in the meantime, have fun correcting!
View more information: https://www.fool.com/the-blueprint/color-correction/