Photo: DPReview staff

As part of DPReview's 25th anniversary celebration, we're looking back at some of the more significant cameras to come along over the past 25 years, and today, we're highlighting the camera that led the 4K revolution in consumer cameras: the Panasonic GH4. Officially announced in early 2014, we published our GH4 review on October 16, 2014 – ten years ago today.

We've all become so used to 4K video that it no longer registers as unique. It's found on virtually every mirrorless camera made today, smartphones, action cameras, miniature gimbal cameras, webcams, security cameras, and even those wacky $100 'pro' video cameras you see on Amazon and wonder who buys them.

But, of course, it wasn't always that way, and we have the GH4 – the first mirrorless camera to capture 4K video internally – to thank for opening the metaphorical floodgates and ushering in the 4K era.

I had a personal interest in the GH4: as someone who had adopted the GH line early on for video projects, I was as curious as anyone to know how it stacked up. Although I was on staff at DPReview, I wasn't involved in writing the GH4 review and probably read it with as much anticipation as anyone else.

Photo: DPReview staff

It's worth remembering that the GH4 was a hybrid camera designed to appeal to both stills and video shooters, and it had features to appeal to those who wanted to do both. Like the GH3, the camera was built around a 16MP sensor, but it supported 12fps burst shooting (7.5fps with focus tracking), a 1/8000 shutter speed and 1/250th flash sync. It even had a rather lovely 2.36M-dot OLED viewfinder.

But realistically, nobody was buying a GH4 just to shoot stills. You bought it because you wanted a solid video camera that could shoot stills when needed.

"Realistically, nobody was buying a GH4 just to shoot stills."

The GH4 could capture 4K video at up to UHD 4K/30p (3840x2160) or DCI 4K/24p (4096x2160) internally and supported both Long GOP and All-I codecs at bit rates up to 200Mbps. Although we take bit rates like this for granted today, this was very high at the time. The camera also produced pleasing 1080p video, though as we called out in our review, its HD video wasn't as good as the perfectly oversampled 1080p video from the Sony a7s.

Despite the impressive specs and beautiful video to match, we had some nitpicks. To start, 4K video captured internally only had 8-bit 4:2:0 color, providing less flexibility for color grading in post. (10-bit 4:2:2 color was supported, but only when recording externally.) Additionally, the GH4's sensor was 4608 pixels wide, requiring the camera to use a smaller, native crop of the sensor when shooting 4K. This resulted in a 1.1x crop for DCI 4K and a 1.2x crop for UHD 4K.

Equally as crucial as its video specs, the GH4 illustrated Panasonic's commitment to supporting a professional video workflow.

The camera included several now-common tools to improve the video shooting experience, including focus peaking, two zebra settings, control over Master Pedestal (black level) and luminance scale, and a 'cinema-like' gamma preset. It also allowed users to set the shutter speed and ISO as shutter angle and gain and could generate color bars for calibration. It was also possible to switch between capture frequencies, meaning the camera could support NTSC, PAL, and true 24fps cinema standards.

"Equally as crucial as its video specs, the GH4 illustrated Panasonic's commitment to supporting a professional video workflow."

Alongside the camera, Panasonic released the optional DMW-YAGH interface unit. This $1999 accessory unit added two XLR inputs for audio, an SDI input for timecode, four 3D-SDI connectors capable of outputting 4:2:2 10-bit video and a 12V DC power socket. The unit attached to the bottom of the GH4 and felt oversized relative to the camera. Beginning with the GH5, the interface unit was phased out in favor of the DMW-XLR1, a much more affordable option in the style of the hotshoe-mounted XLR adapter we've become accustomed to today.

The GH4 was also the camera Panasonic used to debut its newest autofocus technology: Depth-from-Defocus, or DFD. DFD attempted to build a depth map of a scene by making tiny focus adjustments and analyzing changes in the image. With an understanding of the out-of-focus characteristics of a particular lens, the camera could build a depth map of the scene.

The optional DMW-YAGH 'Interface Unit' provided a more extensive selection of video industry connectors for using the GH4 as part of a high-end video rig.

However promising the technology may have been, DFD never quite met expectations. Panasonic really wanted to make it work, and it's possible that, given fast enough sampling and processing, it might have continued to improve. Unfortunately for Panasonic, cameras using phase-detect autofocus consistently provided a better AF experience, particularly when shooting video, and the company eventually made the jump to phase-detection with the Lumix S5II in 2023, finally arriving in the GH series on the GH7 in 2024.

In our review of the GH4, we found a lot to like and a few frustrations. For example, despite having an autoexposure compensation dial, the camera didn't allow you to use it when using Auto ISO in manual exposure mode, and there was no Auto ISO option when shooting video in M mode. Overall, though, we were mighty impressed and saved our biggest praise for the camera's video capabilities:

"The GH4 was also the camera Panasonic used to debut its newest autofocus technology: Depth-from-Defocus, or DFD."

"It's in terms of video that the GH4 really stands out. It produces some of the best video we've yet seen - losing out only to the Sony a7S's moiré-free 1080 output. The ability to capture good quality 4K, whether for use at full resolution, downsampling to 1080 or cropping to 1080, adds real flexibility to the camera. Low light performance is solid if not exceptional," we concluded.

The GH4 landed in the retail market at a price of $1699, or about $2260 today adjusted for inflation, which isn't far off the $2199 price of the GH7. It's amazing to think about how expectations for video have changed over the years. However, the GH7 has its work cut out for it: rather than being an obvious standout in the crowd, it has to compete in a marketplace of cameras brimming with video features. Maybe in another ten years, we'll look back to see how it held up.