Mediaworks - Color Correction and Color Grading

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COLOR CORRECTION:

  • Corrects the color and contrast of a shot so that it looks true to life and measures correctly
  • Can adjust exposure
  • Can make footage less flat
  • Can correct a color balance issue
  • Can increase saturation
  • Can establish ACCURACY—you want to make sure things in the frame and shown as they really are
  • Accuracy is especially important for flesh tone
  • Can bring proper focus to elements within a frame
  • Makes sure that each shot goes with other shots from the same scene


COLOR GRADING:

  • Adds a visual palette that stylizes the image beyond correction, often providing a specific tone or emotion
  • Helps inform the audience’s perception of a scene
  • Emphasizes different climates, locations, moods, characters, and plot


Color correction is a critical part of the post production process. Following a workflow will help you achieve the best color correcting results.

WORK FLOW:

  1. Correct individual shots for contrast, color balance, and saturation
  2. Establish shot to shot consistency
  3. Stylize your footage to add a particular look to your video

COLOR CORRECTION Work flow 1:

  • Adjust your Luma Values (light and dark values)
  • Adjust your Chroma (color values)

Adjusting Luma:

  • Adjust your image so the black parts and truly black, the white parts are truly white, and the values in between look good too
  • Since the vast majority of every image is made up of grayscale information, this is the essential first step
  • Opens the contrast range

Removing Color Casts:

  • Measure the colors that are supposed to be neutral in your image, black and white, and make sure that they aren't weighted toward any certain color.
  • This improves color accuracy in the entire image
  • Sometimes footage is purposely shot with a particular color cast mind, like with gels and filters, so don’t remove intentional artistic vision

Adjusting Chroma:

  • Adjust the hue and saturation of an image, especially in terms of flesh tones
  • You may need to warm up flesh tones that are too pale
  • You may need to cool flesh tones if they are too red

COLOR CORRECTION Work Flow II:

Establish shot-to-shot consistency to make sure each shot works well with adjacent shots and each scene is cohesive

  • Focus again on skin-tones, as well as the general light and color of the image
  • Set up a “hero shot”—a shot that you feel you got perfectly—and then match everything else against it
  • Hero shots are often master or establishing shots, and then medium shots and close-ups are matched according

COLOR GRADING Work Flow III:

  • Applying a stylizing treatment effectively manipulates the mood of a scene and your audience’s perceptions
  • Color grading workflow is slightly more fluid than color correcting

COLOR THEORY AND PHILOSOPHY:

  • In the world of film and video, there are three colors that make up all the rest; red, green, and blue
  • These three colors begin to mix to form secondary colors yellow, magenta, and cyan.
  • When you're performing color correction, it's always a good idea to have an inherent understanding of how color works together, because, for example, when an image has a color cast that's too blue, what do you do?
  • To remove blue, add its complementary color by bumping up the yellows and oranges
  • What about a way color makes you feel?

Warm and Cool Colors:

  • Cool colors: greens, cyans, blues, magentas, make you think climate and weather that is cold, are associated with calmness and comfort, but also can be seen as eerie and ghostly, and can connote steely, impersonal environments
  • Warm colors: yellows, oranges, reds, and magentas, make you think of climates and weather that is warm and hot, they are often associated with emotions and feelings of passion, energy, and urgency, sometimes they convey warmth and comfort, and lively and rich environments
  • This will all depend on the how colors are used within the content of the film and how they mix with one another to determine the emotion the colors will evoke
  • Magenta is on both the cool and warm scale—depending on the colors it is next to, it can be either cool or warm
  • Color interaction- our brain assesses color by the colors surrounding it
  • Two of the most important colors in video are white and black—they can stand alone or combine with the entire spectrum of colors to produce styles, looks, and emotions
  • White or light colors are used for daytime scenes, representing serenity and peacefulness, or it highlights are blown-out it can give a scene ghostliness
  • Black or dark colors are used for nighttime scenes, representing calmness and stillness, but can also depict darkness in mood
  • There are overlaps of emotions between cool and warm and light and dark and colors can go in completely different directions depending on what they are combined with and what the context is

Saturation:

  • The colorfulness of a hue
  • Highly saturated color palettes often represent vibrance and high energy or mystical environments
  • Muted, desaturated color palettes can represent a dullness or listlessness, sometimes these palettes evoke an old-fashioned or antiquated feeling or desolate environments

SCOPES AND TOOLS FOR COLOR CORRECTING

  • We need more than just our eyes to accomplish color correcting
  • Color correction is a hybrid of art and science
  • Our eyes are good at giving us a direction with both correction and grading, but video scopes can measure the Chroma and Luma values to make our adjustments more precise
  • We will still need our eyes to determine how to treat individual images and to keep things looking natural

COLOR CORRECTING stage 1:

Set Black and White Levels with the Waveform Luma Scope

  • Used to set accurate black and white values
  • This scope shows only Luma information
  • Horizontally it matches the image exactly left to right • Vertically we are given a Luma Scale
  • Black is measured at 0 IRE and white is measured at 100 IRE • Skin tones generally fall between 60 and 80 IRE
  • The level continuum in Premiere Pro has shadows, midtones, and highlights control
  • There is also a curves option where the adjustments of shadows, midtones, and highlights are controlled by a manipultable curve
  • Adjustments like brightness or contrast don’t get the job done as well because they are uniform adjustments
  1. To bring up this scope go to the Window menu > Lumetri Scopes > Under the wrench icon Select > Waveform > Waveform Type > Luma
  2. Sync up all the parts of the image with the scope so you understand what’s being depicted
  3. Come to the Color Workspace in Premiere Pro to activate the Lumetri color
  4. Navigate to the Color Wheels and begin adjusting the sliders for Midtones, Shadows, and Highlights
  5. Bring your shadows down toward 0
  6. Adjust the highlights by deciding what you want to be white in the image, if there isn’t anything true white in your image, let the highlights stop around 90 to 95 IRE—when you adjust your highlights the black may ride back up a bit, so you may need to bring them back down
  7. With our black and whites set, make some decisions on your midtones, checking flesh tones around 60 to 80
  8. You only want to kiss or approach 0 or 100 in an image or you’ll crunch your white and blacks, which means the values have clipped and you’ll have crunchy, contrasty image
  9. Now have set our tonal range

COLOR CORRECTING Stage II:

Remove Color Casts with the RGB Parade Scope

  • Used to remove color casts and do color balancing
  • Scope corresponds to the left and right of the image, but three times for each color channel
  • Vertically is the intensity of the color, 0 being black and 100 being white
  • See if the color is weighted to any color
  • Familiarize yourself with how the scope correlates with the footage
  1. Select the Curve section of the Lumetri workspace
  2. Adjust the Curve for each channel
  3. You can also do this using Color Wheels
  4. You can also check your White Balance by taking the eyedropper in the Basic Correction and selecting an object that should be white in your image with the eyedropper

COLOR CORRECTING Stage III:

Correct and Enhance the Hue with the Vectorscope

  • Used to enhance color through saturation and hue values, especially for flesh tones
  • The scope only looks at Chroma values, no Luma values
  • It replicates the color wheel- red, magenta, blue, cyan, green, and yellow
  • Values close to the middle are not very saturated while values close to the outside of the circle are very saturated
  • There is a line between red and yellow that represents where flesh-tones fall, no matter the variance in skin tone, as it registers red blood cells under the skin
  • There are, of course, varying degrees of saturation and luminance among different people
  • Often the flesh-tones extend about a quarter of the way from the center
  1. Under the Curves > Select Hue Saturation Curve
  2. You can adjust the saturation of specific hues based on your footage
  3. You can also do an all-over change in saturation by using adjusting the entire circle on the color wheel or by navigating to Basic Correction > Saturation and using the saturation level increase or decrease

COLOR CORRECTING Stage IV:

Establish shot-to-shot consistency

Start by watching back the sequence to notice discrepancies between shots in lighting, contrast, and saturation.

Display multiple shots at once

  1. To see multiple shots at once for more fine tuned shot-to-shot correction bring the playhead to the hero shot (the shot you will be matching other shots to).
  2. Go to the Window menu and select Reference Monitor
  3. Ungang this monitor
  4. By default the Reference Monitor is ganged to the Program Monitor
  5. This can be changed with the link icon on the bottom left of the Reference Monitor
  6. Now the Reference Image is set
  7. Dock this Reference Monitor in the same panel with your Program Monitor
  8. The Reference Monitor allows you to toggle between showing the Composite Video or the Lumetri Scopes, which can be changed using the wrench icon at the bottom of the Reference Monitor

Sharing corrections between shots with Templates and Presets

Copy & Paste:

  1. Select the Effect (Three-Way Color Corrector, Lumetri Color, etc) in the Effect Controls panel
  2. Cmd + C to copy
  3. Select clip to add the Effect to in the Timeline
  4. Cmd + V to paste

Preset:

  1. Right click on the Effect in the Effect Controls panel
  2. Save as a Preset and name the preset
  3. Under the Effects panel select Presets
  4. The saved Preset can then be applied like any other Effect by either dragging the Preset to a clip in the Timeline or selecting the clip in the Timeline and double-clicking on the Preset in the Effects panel

COLOR CORRECTING Stage V:

Color Grading:

  • Adds a visual palette that stylizes the image beyond correction, often providing a specific tone or emotion
  • Helps inform the audience’s perception of a scene
  • Emphasizes different climates, locations, moods, characters, and plot
  1. Make use of Presets and Copy & Paste during Color Grading to expedite the process.
  2. Use Paste Attributes under the Edit menu if you want to bring over multiple effects applied to one clip from another clip.