A colorchecker is an essential tool for photographers and videographers to ensure color accuracy and consistency in their work. In this comprehensive guide, we will explore what exactly a colorchecker is, why it’s important for image quality, and how to use one properly on set and in post-production.
What is a Colorchecker?
A colorchecker is a chart or card containing an array of colored squares used as a color reference to assess, calibrate, and standardize color reproduction in photography and videography. It acts as a color control target, allowing users to compare colors in a scene to the reference colors on the chart.
The most common and internationally recognized colorchecker is the X-Rite ColorChecker Passport, originally created by GretagMacBeth. This pocket-sized reference contains 24 scientifically formulated colored squares in a variety of hues, tones, and saturation levels based on natural objects like human skin, foliage, and blue sky.
Why is a Colorchecker Important?
Using a colorchecker is critical for several reasons:
- It minimizes color discrepancies between devices like cameras and monitors
- It helps achieve consistent colors across different shooting environments and lighting conditions
- It allows accurate communication of color expectations throughout a workflow
- It facilitates color corrections in post-production
- It ensures proper color rendering for print and web publishing
The reference colors on a colorchecker are spectrally engineered and optimized for DSLR sensors and image processing programs. By including the chart in a test shot, users can tweak settings like white balance, exposure, and color profile to achieve truer, more standardized colors.
How to Use a Colorchecker on Set
Using a colorchecker during a shoot is straightforward:
- Place the chart in your scene. It should be fully visible and illuminated by the key light you plan to use. Position it near your main subject for the most accurate reference.
- Photograph or film the colorchecker at the start of each shoot and any time the lighting is adjusted. Use your camera’s custom white balance feature with the colorchecker to set an optimal white point.
- Record 2-3 exposures at different f-stops to allow adjustments in post if needed.
- Capture images with and without flash to compare color differences between lighting setups.
- Take tight shots of just the colorchecker from multiple angles for better sampling.
- Update reference shots after any significant change like moving locations or switching lenses.
You don’t necessarily need the colorchecker in every single frame, but including it frequently ensures you capture the reference information needed for adjustments. Shooting RAW gives more flexibility for tweaking white balance, exposure, and other parameters later if required.
Using a Colorchecker in Post-Production
The true power of using a colorchecker comes in post-production. The reference colors allow precise corrections and standardization between images and video clips by:
- Setting a neutral white balance
- Correcting color casts
- Balancing highlights and shadows
- Matching hues across multiple scenes and cameras
- Calibrating colors to industry standards like ASC CDL, ISO, and Pantone
Most RAW processors and color grading programs have built-in colorchecker profiling that automatically reads the chart and makes adjustments based on the known reference colors. For example, Lightroom allows you to generate a DNG profile by identifying the color squares which then applies corrections across other images shot in the same conditions. Adobe Camera RAW, Capture One, and DaVinci Resolve offer similar colorchecker-based tools for automating color adjustments.
Manual color corrections like white balancing and curve adjustments can also be performed using the squares as a guide. Oftentimes fine tuning images after the initial colorchecker adjustment yields optimal results.
Types of Colorcheckers
There are a few different options when selecting a colorchecker:
| Colorchecker | Colors | Description |
|---|---|---|
| X-Rite ColorChecker Classic | 24 | The industry standard with mattes squares for white balance and basic color correction |
| X-Rite ColorChecker Passport | 24 | A portable version of the Classic plus adapters for photographing the chart |
| X-Rite ColorChecker Video | 24 | Designed for broader color gamut of video with enhanced skin tones |
| Datacolor SpyderCheckr | 24 | Lower price alternative with similar color squares to Classic target |
| x-Rite ColorChecker Digital SG | 140 | Expanded target for high-end workflows with multiple light sources |
The ColorChecker Passport and ColorChecker Classic are suitable options for most photographers and videographers. The Passport’s small size and white balance adapters offer added convenience on location shoots. Meanwhile, the Digital SG caters more to studio photographers that require calibration for products like fabric across different lighting.
Tips for Effective Colorchecker Use
Follow these tips when working with a colorchecker:
- Use a grey card to set exposure, then the colorchecker to fine tune white balance and color.
- Ensure even, diffuse lighting on the chart to avoid shadows and hot spots.
- Fill the frame as much as possible with the colorchecker for accurate sampling.
- Check for reflections, glare, and chromatic aberration which can skew color accuracy.
- Use software like Lightroom for DNG profiling rather than in-camera color adjustments.
- Take multiple reference shots as lighting changes to track color corrections.
- Replace faded, damaged, or discolored colorcheckers when they are beyond calibration.
And remember, a colorchecker provides an essential reference point but doesn’t replace the need for a calibrated monitor, proper exposure methods, and quality lighting. Use it as part of a holistic approach to achieving great color in your images and videos.
Conclusion
A colorchecker may seem like a simple tool, but it provides invaluable color information to help photographers and videographers wrangle one of the most complex elements of image-making: color. By serving as a known reference, colorcheckers minimize discrepancies, allow accurate adjustments, and help achieve color fidelity from shoot to final edit. They take the frustration and guesswork out of color correction. For these reasons, having a colorchecker in your kit bag is a must for color-critical work.