Join Ashley Kennedy for an in-depth discussion in this video Understanding the color correction workflow, part of Color Correction: Creating a Polished Look in Avid Media Composer.
We've already looked at some main reasons that color correction is important, and we've even seen it in action. In this movie we're going to take a look at the specific workflow that will allow us to achieve the best results. Now the color correction process can be broken into three basic stages, which we've already mentioned. Stage 1 is correcting your luma and chroma values in individual shots, Stage 2 is achieving shot-to-shot consistency, and Stage 3 is applying a specific look or style to your entire show. Again, you use both your eyes and the video scopes to do this.
Let's burrow in a little deeper. As we said, Stage 1 is where you correct your individual shots. This is where you adjust your luma, your light and dark values, and your chroma color values, which are made up of two parts: hue and saturation. So, let's break this down. The first step involves adjusting your luma values. First, you set the black part of your image to video black, and you set the white part of your image to video white. This opens up your contrast range, which is not only correct, but is generally much more pleasing to the eye.
Opening your tonal range makes dull and flat footage crisp and bold, and also it makes all other light and color values in your image more accurate. After performing luma adjustments, you should typically clip the luma values, which means that any stray shadows or highlights that register outside legal levels are automatically clamped to be within legal broadcast levels. The second step involves removing color cast and neutralizing your image. This means that you measure the colors that are supposed to be neutral in your image--black and white--and makes sure that they are in fact neutral, which means that they are free from a color cast.
If you find your blacks are too cool or your whites are too warm, then you go about removing the color cast by subtracting the offending color, so that you can achieve true black and white values. Doing this will improve color accuracy in your entire image. Keep in mind though: sometimes footage is purposefully shot with a particular color cast in mind, like with gels or filters. If this is the case, you won't want to remove the artistic vision of those that shot the footage. So make sure you communicate with the director or director of photography about their intentions during shooting.
The third step is adjusting hue and saturation. Once your black and white values are registering correctly in terms of luma and chroma, then it's time for you to make any needed adjustments to your hue and saturation values, especially in terms of flesh tones. Often you'll need to warm up your flesh tones if they are too pale, or you may need to cool them down if they are overall too red. You also have the opportunity to either increase or decrease your saturation. After you've corrected the luma and chroma of each shot, you'll need to work on getting shot-to-shot consistency.
This means that you'll often need to apply your corrections, making sure that each shot works well with the adjacent shots. Often, for example, a master shot might be slightly darker or lighter than the close-ups of the same scene because it was shot at a different time of day. Therefore, you'll often need to just make some fine adjustments to bring everything into the same spectrum. Finally, once you've made the appropriate corrections and made sure everything is worked well together, you can add a stylistic look or treatment to your scene like we saw in the last movie.
It's important that you've done all of the work ahead of time to make everything look good before you apply your treatment. As you can see, there's a distinct workflow that you're going to need to take when color correcting your shots. We'll go over each of these shots in detail, but first we're going to take just a little bit of time to talk about some other things you should consider when performing color corrections.
- Understanding the creative goals of each project
- Setting up the Media Composer environment specifically for color correction
- Performing a correction from start to finish in the HSL group
- Performing a correction from start to finish in the Curves group
- Using color correction templates
- Using the automatic Color Correction effects
- Using Match Color and Natural Match
- Performing secondary color correction with Magic Mask
- Keyframing color correction effects over time
- Creating a look and feel with special treatments
- Automatically correcting a broadcast show using the Safe Color Limiter effect