The color grading process is conducted by a “colorist” – who is often a combination of artist and technician.  He or she uses a variety of tools to manipulate many elements of the picture, including the basic controls over contrast, black level and brightness, as well as the various elements of color, such as hue and saturation.  In addition, the colorist commands a great deal of control over less common elements such as the gamma (midrange) value, image sharpness, and the primary color components of video: the red, green and blue channels.  Add to this the ability of the colorist to isolate individual sections of the image and manipulate them separately from the rest of the picture, and you can start to see how much a color grading session can affect your images.

So why is color grading important for a High Definition project? 

First, the color grading process can be used to apply a certain look to a shot, scene or entire program. It gives the director tremendous creative latitude to tweak and manipulate the most subtle characteristics of the picture to help set a tone or mood.

Second, the various HD formats are capable of recording vast amounts of information on tape.  In some cases, that information takes the form of image detail that can be manipulated through color grading.  Things like skin tones and textures, scenic shadows and highlights, and the full range of colors can be enhanced or suppressed through the color grading process.  Thus the director can maximize the ultimate potential of the captured HD images, yielding vibrancy and brilliance that was captured on the tape, but is hidden until manipulated by the colorist.

Decisions, decisions….

Because HD is video, you can see what you’re recording as you shoot.  This advantage over film has led some people to decide that whatever stylized look they are after can and should be created on set.  However, the benefits of color grading in post often make that an unwise decision. 

For example, when choosing to create a look for a scene or program, the director has the option of manipulating lighting, lenses, filters and other elements on the set to produce the desired look.  Maybe the director wants to shoot a scene that feels cold.  So he or she may employ various lighting and lens filter techniques to lend a slightly blue and crisp tone to the picture. This process, when conducted during the production phase, can be time consuming, tying up cast and crew for the duration of the process. And that kind of time can be very expensive.  It also forces the director to accept much of what was created on the set. And that can be a problem if they change their mind in post.

Color grading has presented another option: to create the look in a post production color grading session. If a director shoots in a straightforward style on the set without attempting to impose a look during the production phase, the color grading process allows him or her to employ the exact same cold blue tint in post, without the expensive on set adjustments during production.  And, with the color grading process, a director can experiment with a full range of stylized looks - risk free: you can always return to the original straightforward style, or try something different.  It’s important to point out that there is no substitute for great lighting and correct use of lenses for image effects like depth of field.  But even these elements can often be manipulated in the post production color grading process.

Shoot for Post

The key to maximizing the potential of the post production color grading process is for the director and DP to ensure that on set lighting has the desired effect on the subjects and the environment. But they should be careful not to ”overexpose” the image.  HD retains an enormous amount of information, but much of the available information is lost forever when the whites and high end of the picture are blown out. When that happens, it is very difficult, and sometimes impossible to recover the image details that are lost. 

On the other end of the scale, information and details that are lost in the low end of an “underexposed” HD image often can be recovered. So, if given the choice, a DP should err on the low side, underexposing an image, rather than overexposing it, with the knowledge that, if desired, an overexposed effect still can be accomplished easily through color grading.

Finally, the color grading process should be conducted after the project goes through HD online editing… and preferably before titles and graphics are added.  The color grading tools are frame accurate (actually field accurate!), and can import the online EDL to ensure that every frame of video is manipulated to achieve the desired results.  Also - and this is important - editing the final version of the program allows the colorist and the director to manipulate each shot or scene relative to the others in the program, to ensure continuity of the look, or to change looks of adjoining scenes to provide contrast.

So, when shooting an HD project, be sure to remember that it’s wise to save some of your creativity for the color grading process during post production. You’ll be glad you did.