One of the many color correction challenges is matching dissimilar cameras used within the same production. This tends to be the case in many web, streaming, and non-scripted projects, where budgets and availability often dictate the mix of cameras to be used. I frequently end up with RED, ARRI, Panasonic, Sony, DJI, and GoPro cameras all in the same show. Most NLEs do include basic, albeit imperfect, shot-matching features. However, now several software developers are taking that challenge head on.
One such developer is New Zealand’s FilmConvert, developers of the FilmConvert Nitrate film emulation plug-in. Their newest product is CineMatch, a camera-matching plug-in that’s currently available for DaVinci Resolve and Premiere Pro – and coming to Final Cut Pro X in the future. As with Nitrate, CineMatch is a cross-platform plug-in that may be purchased for a specific NLE host or as a bundle license to cover all products.
The CineMatch concept is very straightforward. Most productions have a main or “hero” camera – typically designated as the A-camera. Then there are other cameras for cutaways and alternate angles – B-camera, C-camera, etc. The principle is to match the look of the B- and C-cameras to that of the A-camera.
Dealing with color science
Each camera manufacturer uses different color science for their products. Sony will have a distinctly different look from Canon or Panasonic. FilmConvert builds its plug-ins based on camera packs, which are each customized for a specific manufacturer and model in order to properly match that camera’s color science.
If you have a production that mixes a Sony FX9, an ARRI Amira, and a Panasonic GH5, then each uses a different camera pack. CineMatch is designed to work with Log/RAW/BRAW formats, so there are fewer packs available on the CineMatch site than on the Nitrate site. That’s because many of the prosumer cameras supported by Nitrate do not record in log and, therefore, wouldn’t be appropriate for CineMatch. Since CineMatch uses fewer camera packs, all currently-supported camera packs are included in the installer at this point in time.
The basics of matching
To start, disable any embedded LUT or remove any that you may have added. Next, apply the CineMatch effect to the clips on the timeline in Premiere Pro or as nodes in Resolve. On A-camera clips, set the appropriate source camera profile, but no target profile. For B-cams, C-cams, and other clips, set their source camera profile; however, set their target profile to match the A-camera source.
In a situation with an ALEXA A-cam and a Panasonic EVA1 as the B-cam, the ALEXA would only use the ALEXA source profile. The EVA1 would be set to the EVA1 source, but ALEXA as the target profile. Essentially you are moving all cameras into a color space matching the ARRI ALEXA Log-C color science.
To properly view the CineMatch output, apply the REC 709 transform. However, since CineMatch has converted all of these clips into a common log space, such as ARRI’s Log-C, you can also opt to leave this transform off within the clip filter and apply a conversion LUT at a different point, such as in an adjustment layer in Premiere Pro or as a timeline grading node in Resolve. This way, CineMatch is not limited to REC 709/SDR projects.
Additional color correction tools
Ideally the camera crew should have maintained proper and consistent exposure and white balance among cameras used on a common set-up. Even better if color charts have also been recorded at the start. In a perfect world, you’d now be done. Unfortunately, that’s never the case. You’ve unified the color space, but this doesn’t automatically match one clip to the next. CineMatch includes a comprehensive color correction toolkit to further match and adjust clips. There are white balance and exposure controls for quick adjustments.
If you use the split screen comparison view in Premiere Pro or Resolve, CineMatch HSL curves can be used to refine the match between source and target clips. As with Nitrate, there’s a full set of secondary color controls, including wheels, curves, and levels. Not only can you better match cameras to each other, but you can also use CineMatch to cover most basic grading needs without ever touching Resolve’s grading controls or Premiere’s Lumetri panel.
Working with CineMatch
Although this plug-in is marketed for camera matching, you can use it completely apart from that task. That’s primarily because of the camera packs. For example, when you film with a Panasonic GH5 in a log profile, no NLE offers a stock LUT that is correct for that camera. Generally you end up just correcting it without a LUT or applying a generic Panasonic V-Log LUT. That was designed for the Varicam’s color science and is not a perfect match for every other Panasonic camera. Close, but not spot-on. CineMatch lets you apply a correction that is tailor-made for each individual camera profile, thanks to FilmConvert’s development of a wide range of professional and prosumer camera packs.
The second advantage is that you can impart the look of other cameras. For example, I’m a fan of ARRI’s color science and really prefer the look of an ALEXA over most other cameras. I can apply CineMatch to a GH5 clip, set the source profile to GH5 and the target to ALEXA and impart a bit of that ARRI color to the GH5 clip. While it’s not a replacement for shooting with an ALEXA and the color conversion might not be absolutely perfect, it’s a nice adjustment that gives me a better image than working with that clip on its own.
Finally, if you own both CineMatch and FilmConvert Nitrate, it is possible to use the two in conjunction with each other. Just be very careful of the processes and their order. In the GH5/ALEXA example, make the profile conversion in CineMatch. Make no color adjustments there and don’t apply the REC 709 transform. Then add FilmConvert Nitrate, set its profile to the ARRI settings and make your film emulation and color adjustments to taste.
©2020 Oliver Peters