Panasonic’s GH series of compact system cameras (CSCs) have been the hugely popular with amateur and independent filmmakers ever since the GH1 burst onto the scene in 2009. The GH4 made the leap to 4K in 2014, and with its outstanding picture quality, sublime ergonomics and a bumper set of features for both video and stills, there hasn’t been much to challenge it in the last three years. The only credible contender is the full-frame Sony a7R II, but at £2,500 that’s a lot more expensive.
The firm’s design team hasn’t been slacking though, and the Panasonic GH5 ups the ante yet again. It now offers 4K (3,840 x 2,160) video at frame rates up to 60fps, either for high frame-rate footage or for slow-motion playback at 24fps, 25fps or 30fps. Meanwhile, 1080p capture is at frame rates up to 180fps, allowing 7.5x slow motion at 24fps.
There’s an option to record in 10-bit colour, providing four times as many colour gradations per RGB channel compared to the usual 8-bit files. 4K video is captured using the full width of the frame rather than a 3,840×2,160-pixel crop, which delivers shorter effective focal lengths and should boost quality a little. There’s now a full-size HDMI socket, which is much more sturdy than the Micro-HDMI socket on the GH4.
This isn’t just a video camera, though; there are improvements for photographers, too. The camera’s 20-megapixel sensor is new and incorporates image stabilisation, which is handy if you use lenses without their own stabilisation and delivers a dual stabilisation system for lenses that do include it. The electronic viewfinder (EVF) is bigger and sharper with a magnification of 0.76x and 3.7-million-dot resolution. That’s among the biggest and highest resolution EVFs I’ve seen, and it’s a joy to use. One feature that has disappeared is the integrated flash. This allows for better placement of the internal microphone, which perhaps suggests that it’s videographers whose needs are paramount in Panasonic’s mind.
Various other new additions are likely to please both photographers and videographers. The LCD screen has grown a little, to 3.2in and has a 1.6-million-dot resolution. Dual SDXC slots make it easier to manage intensive shoots, with options to overflow, mirror for backup or save photos and videos separately to each. There’s a mini joystick that’s dedicated to moving the autofocus point, although I found it easier to use the touchscreen. The latter can be used for autofocus point control even when composing shots with the viewfinder; you can even with pinch-to-zoom to adjust the size of the autofocus area.
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Panasonic GH5 review: Autofocus
Panasonic is unique among CSC manufacturers in not incorporating phase-detect autofocus points onto its sensors to help with autofocus performance. However, with the GH5 typically taking only 0.1 seconds from pressing the shutter button to capturing a photo there’s clearly nothing holding it back. Panasonic’s Depth From Defocus (DFD) technology measures the amount of blur to estimate the focusing adjustment required so it can jump to the correct focus position rather than hunt through the scene.
This is a new feature since the launch of the GH4 and it does indeed appear to improve autofocus speed. Also new is the ability to customise the subject tracking performance in continuous autofocus mode, similar to the controls offered by high-end SLRs.
When it comes to video, autofocus performance isn’t so much about speed, but rather reliability and smoothness. When tracking a moving subject or shooting with a moving camera, very slight deviations may be forgivable but focus hunting, where the subject goes completely out of focus before locking on again, really spoils a clip. Meanwhile, a deliberate change in focus, perhaps to switch between two people in the frame, should be executed slowly and smoothly.
The GH5’s video autofocus options include two new controls for Speed and Sensitivity, similar to the photo autofocus customisation options but set independently for video. This lets the user choose between a smooth but slow response or a responsive but jittery one. Neither sounds ideal, but I found that somewhere towards the latter end gave the best results for automatic subject tracking.
^ Automatic subject tracking isn’t perfect but it may be good enough for serious use in some situations
Often the safest way to ensure accurate focus for video is to set it manually. This is vastly improved through the introduction of a Focus Transition function, which allows three focus positions to be saved for recall while recording. There’s also a choice of five transition speeds, ranging from almost instant to 15 seconds. A custom option in seconds would have been even better but it’s great to be able to perform precise, smooth, predetermined focus pulling.
^ Using Focus Transition to move between three predetermined focus positions via the touchscreen
It’s a shame that this can’t be controlled from the Android or iOS app, as this would avoid any risk of shaking the camera when touching the screen. Remote control from the app is otherwise comprehensive, including touchscreen-controlled spot focus and metering and manual exposure adjustment.
However, enabling Focus Transition on the camera locks the app completely and, while I’m moaning about the app, I didn’t get on well with the Bluetooth function, which is meant to make Wi-Fi pairing easier but proved to be much more problematic than with previous Lumix cameras.
Panasonic GH5 review: Performance
Capturing and encoding 4K video at 60fps requires a fast processor and lots of memory and that’s good news for still image performance, too. I recorded continuous shooting at 10fps and it lasted for 111 JPEGs or 65 RAW frames before slowing. That’s even better than the Nikon D500, an SLR that’s built for speed. Burst shooting with continuous autofocus rattled along at 7.5fps, slowing slightly when focus needed to be updated.
If that’s still not fast enough you can turn to the 6K Photo mode. This is an upgraded version of the 4K Photo mode that has appeared on recent Panasonic cameras, which captures a 4K video at 30fps and lets you pick individual 8-megapixel frames to save as JPEGs after capture. Capture continues until the card is full, and there’s an option to buffer footage and save frames from before the shutter button was pressed.
On the GH5 there’s a choice of 4K capture at 60fps or 6K (for 18-megapixel stills) at 30fps. 10fps RAW capture is more useful in most cases but the 4K and 6K Photo modes are handy for very fast action such as golf swings or diving kingfishers.