The new Panasonic Lumix GH6 is one of the most powerful camcorders on the market, but one minor flaw in its laptop is the lack of phase detection autofocus. Well, Panasonic has now explained why the new camera has stuck to the older AF technology.
In a surprisingly candid conversation at the launch of the GH6, Matt Frazer, director of business development for Panasonic USA, said he was "very aware that this is not the direction that people expected us to go" with regard to autofocus on the camera. camera, but that "it was just 'We can't possibly get a mod for phase-based autofocus' on the new camera sensor.
Like previous Panasonic cameras, the GH6 uses a version of contrast-detection autofocus called "Depth by Defocus" (DFD). Contrast-detection autofocus works by adjusting the focus distance of the lens to determine where the point of maximum contrast is. It's ideal for stationary subjects and DFD adds subject recognition to the mix to help improve your speed and accuracy.
However, most other camera manufacturers use "hybrid" AF systems that combine contrast-based focusing with phase detection autofocus (PDAF) to great effect. Phase detection works by splitting incoming light into pairs of images and then shifting the focus to align those perspectives. It's generally faster than contrast-based autofocus and better for tracking moving subjects, but it can have knock-on effects on other aspects of a sensor's design, which is partly why Panasonic didn't embrace it in the GH6.
"You have to remember that when we're developing or working on a sensor design, we're working on data based on an older camera; we were working on that around the GH4 timeline," Frazer explained, referring to the camera that it came out in 2014. "You're working on sensor concerns right now. So low-light sensitivity, dynamic range, resolution — those are the things people were most concerned about."
However, those weren't the only things people asked for. "Obviously we're careful, we know people are looking for a PDAF solution," he added. But apparently it wasn't possible to combine this with the other improvements Panasonic wanted to make to the GH6.
"Ultimately, when we were working on the design of this sensor, it just wasn't possible for us to get a mod for phase-based autofocus," said Frazer, saying the priorities were more like faster read speeds. and improved dynamic range.
Interestingly, he added that Panasonic is actively investigating PDAF and other forms of autofocus. "To be clear, that doesn't mean we're not looking at phase-based AF systems. Or time-of-flight AF systems, or maybe something really cool none of us have heard of before," he said. . . "But right now, with this camera, that's what we're going to be able to deliver."
The quotes certainly offer some interesting insight into Panasonic's decision-making process, though they don't go into specific detail as to why the company was unable to combine these other enhancements with a hybrid autofocus system. After all, the new Olympus OM-1, which is another Micro Four Thirds camera, combines a new "stacked" sensor with phase-detection AF points across the entire frame.
Despite the controversy, we found the GH6's autofocus to work well enough in most situations, and you can read more of our first impressions in our Panasonic Lumix GH6 hands-on review.
Analysis: a broader view
Autofocus is a key part of any camera, but its importance depends on what you're shooting. If you shoot mostly static subjects or, like many Panasonic GH6 owners, prefer to manually focus video, then its DFD contrast-detection autofocus will probably be just fine.
Actually, it's only when shooting moving subjects or shooting solo videos, as many vloggers do, that the lack of phase detection autofocus can become a potential problem. These quotes from Panasonic's Frazer, along with an admission that it's "not what people wanted," suggest that the manufacturer acknowledges that the GH6's autofocus has some limitations, despite improvements to its DFD system.
Traditionally, the main drawback of Panasonic's contrast-based AF systems has been "clicking" in the background of videos while searching for the point of maximum contrast, so we'll be happy to see if that's still the case in the GH6. Another possible limitation is that in the GH6's higher frame rate modes, such as 4K/120p, face and eye detection are less effective.
Still, the GH6's system can be quite good for your shooting style, and it's important to remember that autofocus is only one factor that affects a camera's performance from a video standpoint. For example, while cameras like the Canon EOS R5 may have superior hybrid AF systems, they can also be prone to overheating, which shouldn't be possible on the GH6 due to its cooling fan.
The GH6 also promises to have one of the best in-body stabilization systems, so it's still becoming a great tool for vloggers and YouTubers. We'll bring you our full verdict very soon, but in the meantime you can read our Panasonic GH6 hands-on review for all of our initial thoughts.