DSC Labs is a Canadian company that makes colour reference charts for the video and movie industry. Their ChromaDuMonde colour charts are the industry standard for professional colourists. A new range of products consists of DSC Labs’ less expensive and easier to use ChromaMatch Pro and ChromaMatch Lt charts. The colour patches on these charts are arranged in a dramatically different way, making these charts simpler to use. Even if you have no experience with colour calibration for video, ChromaMatch charts are quite intuitive to use. I had a chance to try a ChromaMatch Pro “Handy” sized chart.
The ChromaDuMonde charts DSC Labs makes, fulfil videographers’ most stringent needs for quality and durability. In contrast with other colour reference chart brands, the larger models of these charts have an aluminium frame while the colour patches sit behind a glossy laminated layer. The smaller charts are made of black acrylic. The glossy laminate is not there for show: glossy colours have a larger dynamic range and colour gamut. They are therefore better suited for colour calibration. The Rec.709 ChromaMatch charts are made using the same materials and colour pigments as the ChromaDuMonde charts, but instead of a rectangular ordering of the colour chips, the patches on these charts have an outwards radiating arrangement and come with a digital reference PNG image file.
The ChromaMatch Pro has more colours and is made to tighter tolerances than the ChromaMatch Lt. Just like their ChromaDuMonde counterparts, these charts come in a large range of sizes. The Handy size I received is about the same size as a large model X-Rite ColorChecker for Video. My acrylic ChromaMatch Pro Handy featured six ChromaDuMonde vector colours, 11-step modified EIA greyscales with true black, in addition to four skin reference patches, six highly saturated wide gamut colours, 18 evenly spaced intermediate ChromaDuMonde colours, 100 IRE white and true black chips, 16:9 (1.78) and 4:3 framing bow ties, and last but not least: motion picture framing lines for 2.35, 1.85 and 90% of 1.85.
You can use these charts to colour-calibrate photo cameras as well, but mine was really optimised for video and film shooting. For example, I couldn’t use it for white balancing as the white balance side of my version of the ChromaMatch isn’t an 18% grey. However, a good percentage of DSC Labs’ larger charts — Junior Sized and upwards — are one-sided. All of the smaller charts, Frontbox and down to the ChromaSelfie are two-sided like my Handy model. Although the ChromaMatch Pro (and Light) colour reference chart will be available with a number of standard combinations — CamWhite (mine), Backfocus, 18% grey, split white and 18% grey, Fiddlehead or whatever else is there — a large number of these charts are made with a customised backside, depending on the user’s requirements. Only the colour side is standard.
Finally, DSC Labs told me by way of their National Sales Manager, Anthony Dobrovszky, that some of the larger colour reference charts ordered by in particular rental houses are manufactured as double-sided but with potentially any of two dissimilar charts they like supplied to them. “So in Junior size and up we follow the same philosophy and don’t actually have a part number for one chart combination. You pick whatever you like,” mr. Dobrovszky said.
The ChromaMatch Pro and Lt do always come with their own digital reference colour wheel. This is a PNG file of the centre colour wheel on the actual reference chart. The image file has an alpha layer, so that if you display the PNG on top of a shot of the actual chart, you can compare the colours.
Experiences with the ChromaMatch Pro
Shooting the chart at first proved to be challenging. The gloss creates reflections that may hinder the correct recording of the colours. By closely following the guidelines of the included data sheet and experimenting a bit, I managed to get a perfect shot when using videolights. In daylight, you need to find the right angle for the chart to face the camera in order to avoid most reflections.
Both the ChromaDuMonde and ChromaMatch charts have a colour arrangement that automatically places the colour patches precisely in the corresponding boxes of the vectorscope in Final Cut Pro X, Permiere Pro CS6, Catalyst Prepare and Da Vinci Resolve 12.
But then what? What are you supposed to do to correct for colour registration errors? What I did was this: I loaded the videoframe with the chart clip and the PNG file in Final Cut Pro X. Then I placed the video frame on the Timeline and dragged the PNG file above the clip. With the Transform tools I placed, resized and deformed the PNG image of the centre colour wheel so that it perfectly matched the corresponding circle of the shot. With a mask I turned down the brightness of the few borders outside the colour surface. Finally, I disabled the videoclip on the Timeline.
I then fired up the vectorscope and got a perfect view of the colour spikes of the PNG reference file sitting on top of the disabled videoclip. This gave me a good impression of where on the digital reference wheel the colours are supposed to sit. I then enabled the Timeline again and using Color Finale, I could now move the colours of the chart I shot with my camera close to the reference colours. By switching the PNG reference clip on and off, I had a clear view of what I was supposed to do.
Using the same clip-enable/disable method, I used the waveform scope to adjust brightness. To be quite honest, I was surprised to have spent so little time and effort, and to see the videoclip being rendered with spot-on colours.
It could be even easier, though. If Da Vinci Resolve and the Color Finale plug-in would add a chart matching feature for the ChromaMatch charts, you would only need a few seconds instead of a few minutes to get everything right. Unfortunately, Da Vinci Resolve only supports some ChromaDuMonde charts and photo ColorCheckers, while the beta version of the Color Finale plug-in currently only supports the new ColorChecker Passport for Video.
Even without, there is a considerable advantage to using a ChromaMatch chart instead of others. For example, you can apply your own tone curve starting from scratch. A ChromaMatch Pro colour reference chart cost a bit more than the big X-Rite ColorChecker Video, but for around €500 for the Handy model you get a perfect calibration tool from a company whose charts are used for Hollywood blockbusters, documentaries, broadcast video and everything in-between. The quality of build is simply unmatched and the concept that’s behind these charts is nothing short of ingenious.
Other DSC Labs colour reference charts
DSC Labs also makes white balance and focus charts, as well as smaller charts, such as the acrylic ChromaSelfie to calibrate still cameras. That one has a so-called Fiddlehead Focus chart on one side, which allows you to focus your camera or see how well it auto-focuses. The colour side of the ChromaSelfie is specifically tuned for skin tones. However, the white balance patch is not suitable for still cameras as it’s standard white instead of 18% grey. The ChromaSelfie helps with focusing and with adjusting photos in Photoshop or other editors. The ChromaSelfie helps with adjusting photos in Photoshop or other editors.
They now also offer a Print-a-Match colour wheel to evaluate and adjust colour printers. The Print-a-Match comes with a digital reference file the user must print and then compare with the reference chart on sight. Differences can then be corrected in the printer driver.
The problem with the latter is that you have to rely on your eyes to estimate whether the colours are identical to the reference. Few people have perfect colour sight, however. The evaluation of a printout therefore can’t be more than approximate as you don’t know the expected RGB values of the reference chart to measure them with a spectrophotometer. For office printers, that’s OK. For serious photography printing, it’s not.
Still, it’s clear that no matter what your application calls for, DSC Labs is serious about having a solution or creating one for you.