Final Cut Pro HD | H•O•T Hands-On Training [Electronic resources] نسخه متنی

WARNING | Don't Color-Correct Video Using a Computer Monitor

For this exercise, color correcting on your computer monitor will be just fine, because you are learning the process of color correction. However, computer monitors don't display video images using the same colors as your TV set or, even better, a video monitor.

Video displayed to your computer looks dark and muddy. Shown on a TV set, it looks great. Computer images that looks vibrant and colorful on your computer screen look washed out and lifeless on a TV set.

LCD monitors make matters worse.

In Final Cut Pro HD, Apple introduced the idea of Digital Cinema Desktop Preview (View > External Video > Digital Cinema Desktop Preview). This is a great way to preview your images, but the colors are still not accurate.

The basic rule is this: if you are color-correcting video for real, you must use a cali-brated video monitor in order to know what colors look like. Not a TV set. And not a computer screen.

You need three things to properly color correct video: color correction software, accurate video scopes, and a calibrated video monitor. Final Cut provides the first two, and you need to provide the last.

You've been warned.

1.

Chapter 11 Lesson. Double-click Seq Color Correct to load it into the Timeline.

If you need help in reading the scopes inside Final Cut, please refer toChapter 9," Text, Titles, and Graphics."

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Here are the steps to fixing color problems with a clip:

2.

Start by selecting the first clip, Jerill Big Threat, and choosing Effects > Color Correction > Color Corrector 3-way.

The 3-way filter is used for video and other YUV clips. The Color Corrector filter, also in that same collection, is used for RGB and other computer graphics clips.

3.

Put the playhead on the marker in the first clip, then double-click the Jerill clip to load it into the Viewer.

4.

Choose Window > Arrange > Color Correction. (You can also open the scopes by choosing Tools > Scopes, (or by pressing Option+9), but using the Window > Arrange menu reorganizes all your windows to make color correction easier.)

Again, you can color-correct a clip using video anywhere within the clip; however, if you put your playhead on the marker, your screens will match mine.

The color in this clip is fine, but the black levels are too high, making it look washed out. Also, the color saturation is a bit low.

On the Waveform monitor, the small white dots represent the grayscale values of all the different pixels in the image. Higher dots represent video levels that are whiter than lower dots. The highest dots are called the white level, and the lowest dots are called the black level.

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5.

Switch the scope to Waveform using the pop-up menu in the top-left corner of the Scope window.

See how the black levels, the white dots in the lower third of the scope, are seriously elevated? They are pushing 20%, which is way too gray. Black levels should be down near the line labeled Black.

6.

You fix this using small increments of changenot huge swipes with the mouse. Click the small left-pointing arrow at the left end of the line below the Black color circle on the 3-way color corrector. This line adjusts black levels. Clicking the left arrow brings them down; clicking the right arrow brings them up. Most often, you are bringing down black levels.

In video, color correction is interactive. Making a change to any color affects all other colors. For this reason, I've found that I get the most consistent results by adjusting levels and colors in a specific order: first, black levels, then white levels, then, finally, color hue and saturation.

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7.

Click the left arrow until the black levels start touching the Black line. For me, this was about 37 clicks.

Again, I rarely use the slider because it doesn't have the precision I need. Small increments, slow and steady, work best for color correction.

8.

Next, look at the white levels. Again, a little hot (meaning, too high)around 103%. Here's a tip to help you quickly set white levels: use View > Range Check > Excess Luma (or press Ctrl+Z).

9.

To adjust the white levels, click the white level bar underneath the White color circle. Click the left arrow to decrease white levels; click the right arrow to increase white levels. In this case, bring the white levels down until the vast majority are below the 100% line at the top of the Waveform monitor. When the Range Check switches from the Warning to the OK icon, click twice more to put your white levels into safe territory. For me, this was three clicks for the warning to disappear, plus two more for safety.

10.

Using the pop-up menu, switch to the Vectorscope to check your chroma (which means "color") levels.

The chroma levels are well within safe guidelines, so you can safely increase saturation to warm up his skin tones.

11.

Adjust saturation by clicking the small arrows at the end of the Sat line. The right arrow increases saturation, and the left arrow decreases it. For me, 10 clicks with the right arrow made him look good.

With saturation, unlike white or black levels, there are no special guidelines. So, make the person look good, while still maintaining safe color saturation levels on the Vectorscope.

Before (left) and after (right)

12.

Play the clip. Compare what he looked like before and after correction by toggling on and off the blue check mark in the top-left corner of the Color Corrector 3-way window. Checked means the filter is on; unchecked means the filter is off.

In the second clip of this sequence, Meyers Bad color, you need to correct one of the speakers at the press conference who has a decidedly purple skin tone.

13.

Select the second clip, Meyers Bad color, and position your playhead on the marker. Choose Effects > Color Correction > Color Corrector 3-way, and double-click the clip to load it into the Viewer. If you haven't done so already, choose Windows > Arrange > Color Correction.

14.

First, set the black level. Look at the Waveform monitor. The black levels are up near 10%. Too high.

Click the black level left arrow to pull the blacks back down to 0%. (For me, this was about 23 clicks.)

15.

Then, set the white level. Both the Range Check and the scope agree the white levels are OK. You might pull the white levels up a few clicks, just to brighten the image a bit. However, if the Range Check warning appears, you've gone too far.

Now that both black and white levels are set, it is time to correct the color. Because of how all the different elements of a video signal interact, I've found the most reliable way to do color correction is to follow a strict order of setting black levels, then setting white levels, then adjusting color.

Switch to the Vectorscope. The pink line pointing diagonally up left is called the flesh tone line. All skin tones, regardless of race, will appear pretty darn close to this line, because the primary color of human skin is provided by red blood. Since everyone's blood is the same color, all flesh tones are, in the eyes of the Vectorscope, simply different amounts of red.

By looking at how far someone's skin tone diverges from the Vectorscope flesh tone line, it is easy to see what kind of color correction is necessary to bring them back to normal.

In the case of Mr. Meyers, his skin tone is rolled decidedly toward magenta. This is the last of the three steps to color correction.

16.

To color-balance a shot, click the small eyedropper in the lower-left corner of the White color wheel. Then, click something you believe to be white in the image. Try to pick a part of the image that is not overexposed. In this case, the shoulder of his shirt will work fine.

Before (left) and after (right)

As soon as you click the eyedropper, the color is immediately corrected. The skin tones are right on the flesh tone line. And you are done.

There is a school of thought that says color-correcting on a midtone gray is more accurate. Although I don't argue, my point is that finding a clean white in an image is easier than finding a clean mid-tone gray. This is why I teach this systemit's easy to use and provides dramatically improved results.

However, in this case, you will further improve the image by selecting the mid-gray eyedropper and clicking the gray window immediately to the left of his right ear. In this example, both his skin tone and saturation improve. (I said this was a three-step color-correcting systemI didn't say you couldn't improve on it from time to time.)

17.

Save your work, or not. As you wish. In either case, you are done with this exercise. Keep things open, though; there's still more to learn.