Cinema RAW Light explained

Filming in RAW gives you more options in post-production, but the file format has been hard to accommodate in the past. Canon Cinema RAW Light, first introduced with the release of the Canon EOS C200 video camera, makes using RAW faster and easier than ever.

RAW filming ensures optimum control over picture quality and enables creative and technical decisions to be made later in post-production. Previously, that flexibility had come at the price of large file sizes, making the storage and transfer of 4K RAW files on location and in the edit suite a challenge.

Canon's Cinema RAW Light format alleviates this problem, offering a significant reduction in file size without sacrificing image quality or grading and compositing headroom. Also featured on the Canon EOS C500 Mark II, Canon EOS C300 Mark III, Canon EOS R5 C and Canon EOS C70, the Cinema RAW Light format allows filmmakers to realise the widest dynamic range of the camera's sensor in a file that's approximately a third to a fifth of the size of a standard Cinema RAW file.

In the case of the Canon EOS C200, this breakthrough enables 4K internal recording to a high-speed CFast™ 2.0 card, working out at around 15 minutes of 12-bit or 10-bit DCI 4K at 1Gbps on a 128GB card. (It's worth noting that only CFast™ 2.0 cards that support VPG-130 are recommended for use with Cinema RAW Light.)

The Canon EOS C500 Mark II features a DIGIC DV 7 image processor, which enables Cinema RAW Light recording internally at 5.9K and at up to 2.1Gbps using CFast™ 2.0 cards that support VPG-130. Meanwhile, the Canon EOS C300 Mark III supports continuous recording at higher frame rates of up to 120fps in 4K Cinema RAW Light using CFexpress recording media.

The Canon EOS R5 C introduces three new Cinema RAW Light recording options, while a recent firmware upgrade for the Canon EOS C70 allows users to use Cinema RAW Light to make the most of the camera's breakthrough DGO (Dual Gain Output) sensor.

However, as the processing of a Cinema RAW Light file has to be finished in software rather than in-camera, a number of parameters can be adjusted long after the footage has been recorded. For example, brightness, white balance and sharpness can be fine-tuned in Canon's Cinema RAW Development software. Also, a different colour space and gamma to those set on the camera at the time of shooting can be assigned to the exported file, for example, applying Log 2 (with compatible software) to enable the maximum 16+ stops of dynamic range to be achieved.

The huge amount of information that's captured in Cinema RAW Light is a clear advantage over heavily compressed formats. Shooting 4K at a bit depth of 10/12-bits at 1Gbps produces data-rich files that deliver high-quality results even after a substantial degree of manipulation in post. Cinema RAW Light enables you to achieve the look associated with RAW files at a fraction of their size, making a RAW workflow more accessible than ever before.

"The big thing for me isn't so much that it's RAW per se, it's more the non-chroma subsampled image it delivers," says Ollie Kenchington, colourist and filmmaker at Korro Films. "So you get the full RGB 4:4:4 colour information, which is really important for certain projects."

Canon Europe product specialist Aron Randhawa adds: "Cinema RAW Light allows cinematographers to take advantage of the full capability of the camera, creating a RAW file in a format that conforms to known workflows but with the added benefit of capturing internally to recording media."

Cinema RAW Light features:

• Compact and lightweight format
• Three data rate options introduced on the Canon EOS R5 C and Canon EOS C70: LT, ST and HQ
• 10/12 bit RAW
• Up to 16 stops of dynamic range after development in Canon Raw Development or other compatible software
• Accurate tone reproduction
• Delivers the camera's natural colour response

With the introduction of the Canon EOS R5 C, filmmakers are able to realise the benefits of a Cinema RAW Light workflow in a smaller camera and at 8K resolution. What's more, the EOS R5 C provides a choice of different Cinema RAW Light formats: HQ (High Quality), ST (Standard) and LT (Light). "All three are 12-bit RAW, with no chroma subsampling," says Aron. "The only difference is in the data rate."

As Aron explains, Canon has introduced three different versions of Cinema RAW Light in order to give filmmakers more flexibility. "For a lot of people, shooting 8K/25p RAW at 2.6Gbps in the original Canon EOS R5 was quite demanding. It's a lot of data to put on your CFexpress cards and then a lot for the computer to process, and in general the projects would get very large in terms of file size. But now we've introduced LT at 1070 Mbps in the EOS R5 C, it's making it more accessible.

"The ST and HQ options are for people who don't want to compromise on image quality, and who have the professional workflows to deal with higher bit rates. This could be useful when cropping the image significantly or generating high-end visual effects. Overall, though, the difference in image quality between the three formats is fairly small and almost impossible to tell with the naked eye in a simple scene such as an interview scenario."

Ollie agrees. "It feels like there's a little bit more clarity to ST when compared to LT, but it is very subtle and it really isn't something that I suspect a non-colourist would notice," he says. "I think if I was shooting a project where colour was paramount and we needed that full RGB, and maybe we were planning to apply some sharpening in post, over and above what you would normally do with developing RAW, then I think ST would be the route I would go down for certain projects. But LT is perfectly decent and if you're just after a really robust 4:4:4 codec that's full of colour information, and not just using extra data that you're not really going to benefit from, then LT is perfect."

It's worth noting that the HQ mode is available only when shooting in Super 35mm and not in Full Frame. That's simply because of the limitations of CFexpress 2.0 Type B media. "We can record up to 2.6Gbps onto those cards reliably, and we don't exceed that," explains Aron. "So we're able to unleash 8K 60p with Cinema RAW Light LT, and if you want to go to Cinema RAW Light ST for even more data then you can go up to 8K 30p. If you decide to raise the data rate with Cinema RAW Light HQ, then you'll be restricted to 5.9K and Super 35mm, but this still delivers an exceptional amount of detail for any professional 4K workflow."

In early 2022, the Canon EOS C70 became a Cinema RAW Light capable camera via a firmware upgrade.

"When it was launched, the EOS C70 was able to record in 4:2:2 10-bit XF-AVC or HEVC," Aron says. "One of the biggest requests that we've been hearing from EOS C70 shooters is the ability to shoot RAW, and it's now possible to do that thanks to the three different versions of Cinema RAW Light."

The EOS C70 records onto UHS-II SD cards rather than the CFexpress 2.0 Type B format used by the EOS R5 C and EOS C300 Mark III. However, you're still able to record 12-bit RAW files internally rather than to an external recorder.

"With Cinema RAW Light LT, you can record 4K up to 60 fps in 12-bit on the EOS C70, with ST giving you access to 4K up to 30 fps," Aron reveals. "When you go into HQ mode the image will be cropped to Super 16mm, providing 2K at up to 60fps.

"Cinema RAW Light is a huge benefit for this camera, because it's taking the capabilities of the DGO sensor to a whole new level. We are now getting 12-bit RAW capabilities, whereas before it was chroma subsampled to 4:2:2 10-bit. When you factor in the sensor's 16+ stops of dynamic range, I think a lot of people are going to appreciate all of that extra quality."

Canon has worked with its partners to ensure that the Cinema RAW Light file format is supported natively by a range of popular non-linear editing systems (NLEs), meaning that CRM files can be viewed, edited and graded in software without the need to create an intermediary file, saving both time and disk space.

"In many ways RAW codecs are all the same and they all have similar workflows in post," says Ollie. "But certainly, in my experience, Cinema RAW Light is one of the easiest to play back on not particularly powerful computers.

"I'm always a bit surprised at how well it responds, given that it is a RAW codec. It almost feels like working with Apple ProRes 4444, which is a non-RAW full RGB codec. But you can, of course, change ISO and sharpening and noise reduction and lift gamma and gain, and all these other things that you can do non-destructively as part of the first grade because it is a RAW format.

"The fact that there's now an internal proxy recording workflow available in the Canon EOS C70 via the latest firmware is also great. It solves an editing problem, because you're getting a half-resolution XF-AVC video file recorded with the same timecode and the same file name as the Cinema RAW Light file. So you can do all of your editing with the proxy and then just switch over to the Cinema RAW Light file when you're going to do all of your grading and noise reduction at the end."

In addition to recording Cinema RAW Light, the Canon EOS C200 also shoots 4K UHD (4:2:0 8-bit at 150Mbps) and Full HD in MP4 or XF-AVC, while the Canon EOS C500 Mark II, EOS C300 Mark III, EOS C70 and EOS R5 C all support recording in Canon's XF-AVC format in 4K 4:2:2 10-bit.

Director Brett Danton was among the first filmmakers to use Cinema RAW Light while recording this Jaguar F-PACE SUV commercial in New Zealand on pre-production Canon EOS C200 cameras.

The production schedule required visits to multiple locations in a short space of time, meaning that a mobile setup and easy data management were priorities. It's a combination for which the large amounts of data and smaller RAW file size offered by Cinema RAW Light are perfectly suited. The ability to record RAW internally to CFast™ 2.0 cards on the compact EOS C200 provided the image quality and flexibility that Brett and his team needed, while the camera's MP4 proxy files meant that offline edits could be made on location and reconformed to RAW when the team returned to the UK.

The shoot took place in a range of weather conditions, but it was essential that the colours of the vehicle were rendered accurately from shot to shot. The wide dynamic range and accurate reproduction afforded by Cinema RAW Light ensured that continuity was maintained between scenes recorded in full sun, rain, snow and fog. Other considerations included green screen and composite VFX, in addition to HDR finishing, all of which benefited from Cinema RAW Light's wide colour space and bit depth.

An example of where Cinema RAW Light shines is in the opening shot of the commercial. The combination of high-contrast sunset scene and VFX stag required both an extensive dynamic range and a detailed file that would ensure no image degradation. Cinema RAW Light provided both, with Brett able to decide, in the comfort of the edit suite, whether Canon Log 2 or Canon Log 3 would produce more shadow detail.

Recording detail in the interior of the dark car and the bright, snow-capped backdrop in a single shot posed its own dynamic range challenges. Brett points out that his colourist would normally need to do a two-pass grade for a scene like this – one for the interior and one for the exterior – and then comp in Flame, the 3D visual effects software. Shooting Cinema RAW Light gives you the option of manipulating the raw sensor data, refining the brightness and expanding the dynamic range of the output file before grading so that it can all be done in a single pass.

Obviously RAW won't be needed in every situation, and even the additional processing required for Canon Log may be a step too far when the priority for clients is a fast turnaround. But when picture quality counts and HDR and VFX-heavy workflows are required, Cinema RAW Light provides the perfect base from which to work.