It's not all unicorns and rainbows.
There's a lot to like about the EOS R5 and R6 cameras. The EOS R5 is the latest full-frame mirrorless flagship capable of recording 12-bit 8K RAW internally. Read that again. 8K RAW internally. And that's on a camera body that can get lost in a backpack. It's a great time to be a filmmaker.
However, there are some things about the EOS R5 and R6 that are not so great. But keep in mind, it's based off of information provided by Canon and nothing has been tested in a real world setting. Meaning, initial thoughts can change when production models arrive. Here are some of the standouts, both good and bad.
Traditional Full-Frame Sensor Size
The EOS R5 and R6 continue Canon's tradition of using a 36 x 24mm sensor size. When filmmakers say full-frame, 36 x 24mm is exactly what should be imagined. Having a sensor that exact size makes calculating crop factors easier. Obviously, when owning a camera that's slightly different than "full-frame" you get used to the math, but the universal size is very filmmaker friendly. Thankfully, the company's marketing departments have caught on and have started to use other terms when it's not full-frame. Though sensors larger than full-frame still use a mishmosh of terms.
The sensors on the EOS R5 and R6 both oversample to produce crisp, clean video. The R5 oversamples 8.2K for 8K RAW and 4K DCI files at different frame rates. When recording 4K UHD, it oversamples 7.7K at 23.98, 25, and 29.97fps when 4K High Quality mode is enabled. The EOS R6 oversamples at 5.1k for its 4K files.
In-body Image Stabilization
Both the EOS R5 and EOS R6 have 5-axis in-body image stabilization. When combined with RF and EF lenses that have optical image stabilization (IS), the cameras can provide up to 8 stops of correction. When a lens doesn't have IS, it will rely completely on the body. What's being done under the hood is pretty remarkable. The lens CPU and camera's DIGIC X processor are coordinating all the info—the angel of speed and motion—and is able to calculate the body and lens to give you smooth video. And to be clear, it's not image process stabilization but IBIS from the sensor shift itself.
This might have flown under the radar, but the EOS R5 can record a 12-bit 8K RAW signal and simultaneously record a 4K MP4 file at the same time. What Canon has done here is create a nice proxy option to allow editors to quickly start editing the 4K files as most modern computers can handle 4K workflows. The RAW video file will record to the CFexpress card, and the SD card slot will record the 4K file.
The EOS R was a first-generation camera, and it was undoubtedly going to be improved. With the EOS R5, Canon could have incrementally improved the camera by simply going to a full 4K sensor readout and adding a few features. The company did not. Instead, they pushed the competition forward and added internal 8K RAW.
Though companies like RED have been touting 8K recording for a while and seeing it on a camera body of this size is impressive. It's reminiscent of 2008 when Canon unexpectedly added full-HD video to its EOS 5D and 7D Mark II DSLRs. While the 8K RAW image quality of the R5 needs to be tested first, at least on paper, things are progressing—which is good for filmmakers.
EOS R6 Crop
There is a crop factor shooting video on the EOS R6. It's around 1.07x and it's important to be aware of it. When the EOS R was released, some shooters were not happy with the 1.7x crop in video mode. The crop put the EOS R images around a Super 35, but those wanting to shoot the full width of the sensor were disappointed. While the EOS R6 doesn't clear that up entirely like the EOS R5, there is an improvement.
8-bit 4:2:0 Recording
It's still alive. You have to wonder when 8-bit 4:2:0 will shed its last tear. As far as the EOS R5 has come, Canon couldn't quite make it completely over the 8-bit hump. The format still makes an appearance shooting 8K and 4K when Canon Log and HDR PQ are both turned off. 8K uses the H.265/HEVC codec and 4K uses H.264 / MPEG-4 AVC. While this isn't a big disappointment, it's worth pointing out where things still are with smaller camera bodies.
Max Recording Times
The EOS R5 has maximum recording times depending on the video format selected. 8K movie recordings are restricted to 20 minutes depending on the format and frame rate. The same goes for uncropped 4K 60p which has a maximum recording time of around 25 minutes. Canon says this is due to an increase in temperature which makes sense since there it going to be overheating when you can't put a fan in the body or a cooling system that negates the heat. When the camera does overheat, it will shut down and will need time to recover. How much this affects workflow will be a case by case basis.
Canon has also slapped a 29 minute and 59 second record limit for all other 4K recordings. But why?
It's may not be because of overheating issues. You might recall Sony doing this with its Alpha series, or Nikon capping the record limit to 29 minutes and 59 seconds. While there's a workaround to disable the 30 minute time limit on Sony cameras, others are out of luck. At least for now.
The reason for the limit is because the European Union created a law in 2006 that added an import duty of 5-12% on any video camera. What determined if a camera was video camera was if it could record longer than 30 minutes. So companies decided to cap the video clip lengths to keep from paying the tax. The EU is expected to change this.
This is a somewhat hard one to complain about, especially with the research and development behind 8K RAW and the added in-body image stabilization. It's also fairly competitive to other cameras with similar specs, but as a consumer, prices can always be lower. The EOS R5 body is $3,899, which is priced at about $100 less than the Panasonic LUMIX DC-S1H. This was probably done on purpose to entice those still deciding between Panasonic and Canon.
But what raises an eyebrow is the EOS R6. The body alone retails for $2,499, which is acceptable when comparing it to the EOS R5 alone. But if you already own the EOS R, upgrading to the R6 may not be worth the cost. Spending a few thousand dollars for an improved sensor and IBIS on a camera that still has a crop factor seems like a waste. If you don't own an EOS R and are first stepping into the mirrorless world, the R6 is an option worth considering. You also might want to wait and see if the EOS R drops in price in the coming months.