Color Grade When All Light Is One Color
Color grading is how you enhance or alter the color of a video, film, or image. Let's explore color profiles, LUTs and how to color grade.
There are many elements that work together to make a video special but color grading can completely transform the look. Whether subtle or ultra-stylized, how you color grade is optional and depends on your aesthetic. So, what exactly is color grading and where should you start?
What is Color Grading?
Color grading is how you enhance or alter the color of a motion picture, video image, or still image. It's how videographers adjust the colors of their footage to achieve a visual mood or tone.
Color grading was once called color timing, a process done manually while developing actual film. Color adjustments were made by manipulating how long the film was exposed to the different developing solutions.
While the term color grading refers to the whole process of adjusting the color from the source file to the final output, the process is split into two parts:
- Color correction: The process of adjusting the basic color and white balance, exposure, and contrast to be consistent from shot to shot.
- Color grading: Once the color has been corrected, the footage can be color graded to fine tune the colors and create a specific look.
A common example you've likely seen in films is to add teal to shadowed areas and orange to the midtones.
Camera Color Profiles
When a camera records a scene, it collects digital data and then translates that data into a viewable format. When it does this, it includes instructions on how to modify the data in some way to try and more accurately recreate what you saw.
However, no camera is able to do this perfectly, so this is where color profiles come into play. Color profiles work similarly to white balancing, but also adjust elements like saturation and contrast.
Usually color profiles are sufficient for casual situations like taking a quick video of your friend's soccer game. However, videographers need far more control over their footage.
Most cameras will offer a flat or log profile. In a log color profile, the camera minimizes the contrast in order to squeeze in the most information possible. This helps to avoid blowing out highlights or clipping shadows, as well as flexibility when editing your video later.
If your camera doesn't offer a log profile and you plan to color grade your video, use either a neutral profile or set up a custom profile with the sharpness and contrast set as low as possible. It can also help to slightly decrease the saturation setting.
[table id=color-grading /]
LUTs were once used when sending video from editing to print. Different types of film react to development differently. They ensured the printed film matched the monitors where the color correction took place. Without a LUT, no matter what color correction and grading process was used, the final video colors would be unpredictable.A LUT is a set of math-based directions used to modify RGB values that changes a video's hue, saturation, and brightness.
While few video creators (with the possible exception of Hollywood filmmakers) will ever put their videos onto physical film, the LUT process has nevertheless continued. There are two general types of LUTs that digital video editors will use: technical or normalization LUTs and creative LUTs.
Technical or Normalization LUTs
Most videographers are going to use a log color profile in order to capture the most possible information. Straight out of camera, this footage is going to be flat and washed out.
A normalization LUT converts the log image into another color space. It adds back the contrast and saturation compressed during recording. It might, for example, convert it into a Rec. 709 profile in order to match the standard for HDTVs.
Camera manufacturers often supply technical LUTs for their proprietary log profiles. There are also third-party creators developing LUTs they feel are better.
Creative LUTs
Another common type of LUT are creative LUTs. They apply a set of adjustments to different color levels in order to create a specific look or effect. A creative LUT is similar to a preset that a photographer would apply to a picture in Photoshop or Lightroom.
How to Color Grade
The color grading process will vary somewhat from editor to editor, but here is a general workflow you can follow:
-
- Normalize Your Video Clips
- Perform Video Color Correction
- Color Grade Your Footage
- Perform Final Color Adjustment
- Consider Vectorscopes and Skin Tones
Normalize Your Video Clips
The first step should be to normalize your video clips. You need to fix the contrast and saturation in order to take advantage of all of the information recorded. It's possible to do this process manually, or you can use a technical LUT to simplify your workflow.
Perform Video Color Correction
Once your clips have been normalized, you need to color correct the video. Try to get the video clips as "correct" as possible. If your exposure is bad, contrast is missing, or white balance is off, the actual color grading will be far more difficult.
Color Grade Your Footage
Once your color correction is completed, you can then color grade your footage. Again, this step can be done either manually or with a LUT. Doing it manually will provide you the most control but could take longer. Using a creative LUT can save time and add consistency, but only if all of your clips are color corrected well.
Perform Final Color Adjustment
As with any automated method, LUTs are likely to not be perfect. For example, they might give everything too much of a certain color tint. After adding your LUT, go back through, correct any problems, and ensure consistency across all of your clips.
Vectorscopes and Skin Tones
One of the challenges with color grading video is that you can't always completely trust what you see on your monitor. Bad (or the lack of) monitor calibration and ambient lighting can alter the way you see the video being displayed.
How can you make sure that your color corrections are accurate?
Editing programs that offer video color correction tools, such as Adobe Premiere Pro, DaVinci Resolve, and Final Cut Pro offer solutions for this problem. Within these programs, there are panels called scopes that give a range of information about your video footage. FilmConvert is a helpful color grading software package to consider.
When it's time to color correct or color grade, the vectorscope is extremely helpful. A vectorscope shows what color tones you have and how saturated they are. Because the vectorscope directly reads the digital signal, it's not affected by anything that might skew your perception. Once you learn to read them, they give you color information that you can trust to be accurate.
One of the most helpful features of a vectorscope is a line that passes between the yellow and red points. If it was a clock face, the line would go from roughly 11:00 to 5:00. This is called the skin line, because virtually every person's skin tone will fall on or extremely close to this line.
When color correcting, ensure that your colors are balanced so that the skin tones match up with the skin line.
For any videographer who wants to produce high quality content, there are many elements to pay attention to. Framing, focus, exposure, capturing clear audio, and telling an engaging story are crucial. With all of this in place, color correction and color grading play an important, final role in taking your video to a professional level.
How to Color Grade Public Domain image courtesy of Freestocks on Flickr
Tags: DCI 4K, UHD 4K Last modified: July 7, 2021
Color Grade When All Light Is One Color
Source: https://www.borrowlenses.com/blog/color-grading/