In this article we’ll learn how to use the DSC Labs OneShot, X-Rite ColorChecker (or Macbeth) or the DataColor SpyderCheckr with Davinci Resolve to match color. If you’re new to Resolve, I recommend you read my DaVinci Crash Course for Beginners before proceeding.
What exactly do I mean by ‘match color’? Match to what? Here are four broad cases:
- Match different cameras
- Match colors for product or branding so it looks like the real thing
- Get dailies to match each other, though they may have been shot on different days, white balanced incorrectly or under different lighting conditions
- Get colors to fall into an accurate color space for broadcast delivery
Why not just white balance?
Here’s the thing. White balance balances white to a certain Kelvin rating. This does NOT mean everything else (colors, black, etc.) will also match ‘what you’re used to’.
If you have been shooting with Camera ‘A’ for years, and then buy another camera, you’ll notice the colors are ‘off’. You’ll put it down to ‘presets’, profiles, LUTs and what have you, and finally blame it on the camera. This is all true, but it won’t get you beyond the fact that you can’t get the colors you’re used to.
The round-about way of getting the colors you want is with grading. But what if you could do it right in-camera, and get the colors you want with a click of a button? That’s what we’ll be looking at in this article.
Oh, and about the white balance thing, keep reading till the end.
It’s not about grading!
Remember, color charts are not about color grading, but getting colors to match a known standard. I won’t use the term ‘get accurate color’ because that’s plain wrong. There’s nothing ‘accurate’ or ‘inaccurate’ about color, only in reference to a known standard. One such standard is Rec. 709.
Here’s the question: Can you use a color chart to get Rec. 709 colors and call it a day?
Answer: Yes and no. You can use the color chart to get Rec. 709, but you can’t call it a day. The moment you start grading again, you might go beyond what is acceptable color under Rec. 709. Traditionally, colorists monitor this by keeping a strict eye on the Vectorscope.
Now here’s my counter-question: if you need the vectorscope anyway, why bother with a chart in the first place?
For this reason, I do not advise falling under the spell of using a color chart for grading purposes in the mistaken belief it is any good. In fact, you might not like the way DaVinci Resolve ‘crunches’ color when you apply the Color Match Palette function. It might be better if you did it yourself with the grading tools provided. You’ll never know until you try both!
So, before we move on, I only advise using color charts to ‘match colors’, as defined in the first three cases written in the beginning, and not for the fourth case, which is grading.
The Color Match Palette in DaVinci Resolve
As of DaVinci Resolve 11, there are three standard color palettes available to match colors, based on the following charts:
- Macbeth or X-Rite ColorChecker (the original, not the Passport)
- Datacolor SpyderCheckr
- DSC Labs OneShot (including the Pocket version)
I own the DSC Labs OneShot Pocket (for which I paid about $175 including shipping).
Five reasons why I opted for the OneShot Pocket over the others:
- It is designed for Rec. 709 and that’s what I shoot.
- The Pocket is smaller and easier to carry around.
- The Pocket can be hung over a light stand or your nose, so no need to buy this $362 monstrosity.
- It is the cheaper one.
- To be honest, it was Art Adams’ enthusiasm for it that made me buy it. My wallet was happy with the X-Rite ColorChecker.
How to use the DSC Labs OneShot, X-Rite ColorChecker or DataColor SpyderCheckr
All charts work the same way. I hold the chart vertical because that’s how the lanyard faces. It doesn’t matter how you hold it because DaVinci Resolve gives you a ‘matte’ that you can rotate and scale so the colors line up:
It is important to have the chart facing the camera to ensure there is no glare on the chart that shouldn’t otherwise be in the shot either. What you’re looking for is to light the chart with your key and fill, but not your backlight. If you’re in a mixed lighting situation (or if you’ve used gels on one of the lights but not the other) it is possible to have one side of the chart under a different light, and this should be avoided. Choose the most important region in your shot. In my case it happened to be my left nostril.
Ideally, if you’re shooting skin tones (humans) then you might want to have a human in the frame for reference. In the above image, I’m presumably the human, with a white shirt (not so white, as you can see) and a black background.
Also don’t forget, never touch the front or back of the charts, and always hold it by its edges. You don’t want to transfer dirt or grease (or worse) to your lovingly printed color patches or chips. I received a pouch with my chart, and this is how it should be stored or transported. I might even wedge it between by iPad case or a book to ensure it doesn’t get bent.
For those of you using the OneShot Pocket, the SMPTE logo divides the green-magenta line and it is a pain to get it aligned, though not impossible. Similarly, on the back, the logo divides the white and middle-grey areas and you have to be careful not to get it into frame while white balancing. It’s always better to keep it larger than I have, possibly by zooming in.
Finally, all charts have a life-period. Just like how ink fades on paper, these charts cannot be guaranteed to work beyond a couple of years. In fact, none of the manufactures guarantee 100% accuracy in writing anyway, so use your judgement – you know, the one you get after two years of using it.
How to match colors using the Color Match Palette in DaVinci Resolve
First, load the image or video clip that has the recording of the chart into the Media Pool and bring it into the timeline. Move to the Color tab.
To access the Color Match Palette, go to the Color tab in Resolve and select the second icon (as of Resolve 11). This is what it looks like:
You have the following settings:
- Source Gamma – what was your camera gamma? I was using a Canon DSLR and was shooting Rec. 709.
- Target Gamma – for broadcast, DVD, etc., choose Rec. 709. For the Internet, choose Rec. 709 or sRGB, both of which should be tested. For DCP, use DCI P3, though this is beyond the scope of this article.
- Target Color Space – for TV, DVD and the Internet, choose Rec. 709.
- Target Color Temperature – for Rec. 709, the white point is D65, or 6500K. Don’t change it.
- Target White Level – the default is 0.9 or 90% IRE, which corresponds to studio swing. Leave it as is.
I would leave all the adjustments as-is. This is not the tool for making any color modifications.
The next step is to click on the same icon in the viewer and select Color Chart:You’ll get the matte on screen as shown in the second image. Pull the corners to align the matte to your chart as shown. When you’re absolutely sure the squares align with the right chips, click Match. You will see two things happening. First, to the image:
You can see how the colors have shifted. And I’m relieved to see my shirt a bit whiter. Now, did I white balance incorrectly? Of course not! Resolve shows you the variance from the original:
Note how the variance with white and grey is 0% (2% error is an acceptable error tolerance). That means the white balance was spot on. After all, I used the same chart for it!
However, what changed are the colors. This is why white balancing, though an important step, doesn’t guarantee that colors match. It won’t, especially when you’re dealing with different camera-makes.
Just for reference, the above image was shot under 2900K tungsten lights, and one was bounced off the wall, which is beige. Canon DSLRs are known to introduce a slight green tinge to images, maybe that explains the green-blue variance.
What next? How do we use this? All that’s left to do is ‘match color’, that is –
- To match cameras, do this for each camera and you have a common reference base from which to start your grade. You can also use the worse camera as reference and ‘tune’ the better camera to match it.
- To match colors for branding or product, generate a LUT and apply it to the rest of your footage shot under the same lighting conditions. Remember, if the light changes outside, the conditions have changed, but the chart should allow you to pull it back to the same look. Also don’t forget, branding and product usually also conforms to Pantone, and that is another circle of hell altogether.
- For dailies, generate a LUT as above and apply it to your footage prior to transcoding. This works even if you have white balanced incorrectly. Of course, for different lighting conditions, you cannot use LUTs and must do this step every time.
As you might have guessed, creating a LUT for color grading is stupdity itself. Every lighting condition is different. Please don’t use it for grading.
If you do, please don’t credit me.