Using the Macbeth Chart

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This blog is in response to a posting I saw on the Avid Community Forums from a user demoing the use of the Greta MacBeth color chart with Media Composer for removing color casts and such from a shoot. The forum thread and demo video can be seen here His YouTube demo video can be seen here.

I think it’s great that users participate in sharing their solutions and taking the time to make demo videos. In this case, I wanted to show how the same concept of using a chart but with much fewer steps.  This is a demo that I used to do at the Sundance Film Festival Digital Center for filmmakers over the years.

A quick and silent demo video can be seen here. It’s bad enough you have to see me, I did want to subject you to my talking as well. But the concept is pretty easy to grasp; Instead of reading numbers from the color picker and making a best guess as to which part of the luminance scale to change values, just click the target value and use the “match” feature to complete the task much faster while creating a nice curve rather than truncating shadows and highlights in trying to accomplish the same thing.  You can download the digital version of the MacBeth chart I created here. Just make sure to import as 601/709 so that the RGB values are not changed. The numbers may not be exact, but are close enough for a quick starting point in getting a better looking image quickly. Of course as with all color correction, scopes, proper monitoring, are needed.

For additional and related information, Art Adams helped design a better chart for video work and speaks to the limitations of the MacBeth chart here.

Addendum: I forgot to mention that the reason for picking a black point on my shirt was to find the blackest reference point in the frame.  The black square on the Macbeth chart can never be a true black due to the fact that it’s reflective. Some color charts used to have holes, or black felt and such to reduce reflection in order to get a true black. Peter Fasciano, a good friend who has taught me a lot over the years gave me a small empty tomato paste can lined with velvet, that one would point off axis to the lens. Now that was black! Thanks Peter! I just didn’t have it with me the day we shot these test scenes.

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