Panasonic GH4 Review

Panasonic Lumix DMC-GH4 with 4K Video Announced: Professional Camera with Video Features

Actually the new Panasonic Lumix DMC-GH4 is a mirrorless system camera of the top class. However, Panasonic’s main focus in the GH series is increasingly on video functionality and the GH4 is the first digital photo camera that can record videos in 4K resolution – i.e. with 8 megapixels in each of the maximum 30 frames per second. This sounds exciting even for action photographers, because extracted still images of this resolution are suitable for daily newspapers or high-quality DIN A4 prints. But there has also been progress in the photo functions.

Short evaluation

Pros

• Cautiously tuned noise reduction
• Robust, splash-proof housing with good ergonomics
• Very high serial frame rate with large buffer memory
• Outstanding video capabilities

Cons

• Lightweight focus pump for video recording
• Not completely neutral colour rendering
• No shooting modes (motives)
• Only available as a set with low-resolution tenfold zoom

So far, Panasonic has avoided the number “4” in the type designation as far as possible, it is considered an unfortunate number in the Far East. But the new flagship GH4 proudly bears the number “4” – it also stands for the GH4’s ability to record videos in 4K resolution. No system camera can currently provide such a high video resolution. So it’s hardly surprising that Panasonic has equipped the GH4 with a wealth of features for video enthusiasts. Some photo enthusiasts might ask themselves how the GH4 holds up to the classic virtues of a photo camera.

The Panasonic Lumix DMC-GH4 features a new 16 megapixel live MOS sensor with 4K video recording. [Photo: Panasonic]

The new shutter of the Panasonic Lumix DMC-GH4 allows shutter speeds of up to 1/8,000 second and is designed for 200,000 releases. [Photo: Panasonic]

The folding and rotatable 7.5 cm screen of the Panasonic Lumix DMC-GH4 now uses an OLED display with 1.04 million pixels. The OLED viewfinder even resolves 2.36 million pixels. [Photo: Panasonic]

The Panasonic Lumix DMC-GH4 has a pronounced handle and numerous control elements, as is customary for photographers. [Photo: Panasonic]

The Panasonic Lumix DMC-GH4 can optionally be extended with a battery portrait format handle. [Photo: Panasonic]

The Panasonic Lumix DMC-GH4 has a magnesium housing, numerous seals provide splash water protection. [Photo: Panasonic]

The GH4 incorporates a newly developed live MOS sensor that continues to resolve 16 megapixels. However, it can be read out twice as fast and has been optimized for video recordings, for example to minimize the rolling shutter effect. He is supported by the new Venus Engine with quad-core processor for fast data and image processing. For fast shooting series, 40 raw or 100 JPEG shots can now be taken in a row. In bulb mode with exposures of up to 60 minutes, an improved noise reduction is effective, while at low sensitivities the gradation in the 1/3 f-stop could be improved. As with the GH3, the maximum ISO sensitivity is ISO 25.600. Colour reproduction has also been improved and the resolution with a new low-pass filter and better signal processing is said to have increased by around five percent.

For the contrast autofocus, the sensor is read at 240 frames per second, and the new DFD technology (Depth from Defocus) is intended to further accelerate the autofocus. Using two images with different focus, the camera can predict how far the focus still needs to be adjusted to get to the target faster. The autofocus time with the 14-140mm or 12-35mm lens is only 0.07 seconds. However, DFD technology only works with Lumix Micro Four Thirds lenses. The continuous shooting speed at full resolution is now 12 frames per second with mechanical shutter, which in turn now allows a minimum exposure time of 1/8,000 second and should hold at least 200,000 shutter releases. With C-AF, the continuous shooting rate drops to a still impressive 7 frames per second.

Panasonic has increased the number of autofocus points from 23 to 49, allowing you to set any number of autofocus point groups that the camera should use. In addition, there is an infinitely variable single point autofocus in the size of the focal point, which can be flexibly shifted over the entire image field, as well as a new eye detection autofocus in addition to face recognition, which focuses exactly on the eyes. The tracking autofocus, which keeps any subject detail in focus at all times, is further enhanced by a new minimum pendulum function around the focus position, which is particularly beneficial in 4K video shooting. The focus point can be placed on any detail of the subject using the touchscreen, and the autofocus starts automatically when you look through the viewfinder. If you want to focus manually, the GH4 now supports not only a focus loupe, but also a peaking function that highlights sharp contrasting edges in color, even during video recordings.

Panasonic has also improved the viewfinder and screen. The electronic viewfinder consists of a 16:9 OLED display with a resolution of 2.36 million pixels and a contrast ratio of 10,000:1. If required, it can be switched to a black-and-white display for the evaluation of subject contrasts. The magnification of 0.67x remains the same as with the GH3, but the exit pupil rises to 21 millimetres, which should accommodate spectacle wearers; the viewfinder image coverage is of course 100 percent. The switchover is made automatically by means of an eye sensor, whereby its sensitivity can be adjusted or the automatic can also be switched off completely. The screen measures 7.5 centimeters diagonally, has an aspect ratio of 3:2 and has a resolution of 1.04 million pixels. It is also an OLED display, which is also touch-sensitive. This allows you to set the autofocus point, for example, even while looking through the viewfinder, or to adjust camera parameters directly on the screen with a fingertip. Nevertheless, the GH4 has numerous control elements for direct setting of all important recording parameters. Five of the Fn buttons can even be individually assigned functions.

As with the GH3, the housing of the GH4 is also made of a magnesium alloy and is protected against dust and splash water. The GH4 has a built-in flash that can also be used as a wireless controller. The flash system including wireless control is compatible to Olympus like the lens mount. The flash sync time is 1/250 seconds thanks to the new, faster shutter. But the DMC-GH4 can not only flash wirelessly, but also transmit data thanks to WLAN and NFC. In addition, the Lumix can be remotely controlled via Panasonic Image App from a connected tablet or smartphone, including live image display and numerous adjustable recording parameters. What’s new is the possibility of establishing the connection instead of using NFC by scanning a QR code displayed on the screen and recorded by the smart device’s camera, which is very practical for iPhones, iPads and other devices that don’t have NFC, since the network connection no longer has to be set up manually.

In addition to many buttons, the GH4 also has numerous connections. These include a flash sync jack, stereo microphone input, headphone output, cable remote connector, USB, AV output and a 4K micro HDMI port. The SD memory card slot also supports the SDHC and SDXC standards, with the new UHS-3 speed class also being used. It guarantees a minimum write speed of 30 megabytes per second, which is also required for 4K videos. Panasonic is also launching a suitable memory card on the market.

This is not a particularly bulky additional handle for the Panasonic Lumix DMC-GH4, but the professional video interface DMW-YAGH. [Photo: Panasonic]

The video interface for the Panasonic Lumix DMC-GH4 not only has a level meter with level controls, but also numerous audio and video connections, such as XLR and SDI. [Photo: Panasonic]

In addition to semi-automatic or completely manual control, the GH4 also has motif programs and an intelligent automatic function that automatically adapts the camera to the motif if the need arises. A silent mode will turn off the flash, operating noise and AF auxiliary light, and even the shutter will no longer be heard as the GH4 switches from mechanical to electronic shutter. New is also the light and shadow control, whereby in addition to the three presets also three own can be defined. If you prefer to record in raw, but still occasionally need a JPEG, you can do this directly in the camera using the integrated converter. Numerous parameters such as brightness, white balance, color space, shadow and light control etc. can be set.

But the highlight of the Panasonic Lumix DMC-GH4 par excellence should be the 4K video function! This makes the GH4 the first digital photo camera with this high video resolution, and camcorders equipped with this feature normally cost considerably more than the GH4. Although the price of the camera is not yet fixed, it will range from 1,200 (price of the GH3, which remains on the market) to less than 2,000 euros. Both Cinema 4K resolution of 4,096 x 2,160 pixels and QFHD (Quad Full HD) 4K with 3,840 x 2,160 pixels are supported. That’s a full 8 megapixels. However, there is one drawback: In contrast to Full-HD, where the entire sensor is used (2×2 pixels are combined and scaled down slightly), the 4K video function only uses the middle part of the recording sensor. This also means that every pixel is used 1:1, which promises an optimal image quality. A downscaling would not only mean a loss of quality, but would also overtax the processor. In the case of QFHD, this means a further crop factor of 1.3, so the 14-140mm lens does not correspond to a 35mm equivalent of 28-280 millimeters, but to one of 36 to 360 millimeters. In view of wide-angle lenses down to 7 millimetres, however, the initial focal length is still at least 18 millimetres, corresponding to 35mm.

The Lumix GH4 offers such a variety of video formats, bit rates, refresh rates and resolutions that trying to list all possible combinations could fill multi-page tables. Therefore, only a few key data are listed. The video formats MP4, MOV, AVCHD and AVCHD progressive are supported, whereby the GH4 creates seamless files if necessary for seamless recording, but after almost 30 minutes recording is interrupted in Europe due to customs regulations, since the GH4 is a photo camera and not a video camera, for the latter a higher duty is required. The scanning is 4:2:2 and is done either in 8 bits on the memory card and optional additional external recording devices, or one leaves out the memory card and records externally with 10 bits. The bit rate can be up to 100 or 200 Mbit/s, but UHS-3 memory cards are required to reliably store the high data rates. Frame rates are supported at 4K 24, 25 and 30 frames per second, in contrast to the GH3 it does not matter whether the camera is set to NTSC or PAL or is specified for corresponding countries. With Full HD video, VFR also allows higher frame rates to be recorded, about 96 frames per second. At 200 Mbps, ALL-Intra is stored, which means that each of the images in the video is a full frame compressed individually. But also the standard IPB are supported, then the bitrate is maximum 100 Mbit/s. The sound is recorded in high LPCM quality.

The GH4 supports zebra crossing pattern display and the black level can be adjusted by +/-15 steps using the “Master Pedestal” system. The brightness range of the images can be set to 16-235 or 16-255 instead of photo (0-255). The creative video mode offers gamma presets such as “CINELIKE D” and “CINELIKE V” for a cinema look, a synchro scan is available to suppress flickering, for example when recording neon light. New are also the 1 kHz test tone and the color bars according to SMPTE/EBU/ARIB standard. The time code is recorded according to the SMPTE standard either as “Free Run” or “Rec Run”. As an accessory, Panasonic offers a video interface that is screwed under the camera. Here the videographer has not only level displays and controls at his disposal, but also XLR, timecode and SDI connections. Standard mechanical connectors on the interface allow additional accessories to be attached in front of the camera lens. A 12V connector supplies the interface and the camera with power.

Ergonomics and workmanship

Like its predecessor, the GH4 is also very large for a mirrorless system camera. Especially for one that is equipped with a quite small sensor in Micro-Four-Thirds format. And so the GH4 looks more like a full-grown DSLR than a system camera. The hump of the viewfinder swings far up, in addition to a clearly forward pulled handle and a clearly formed thumb rest. This effort in case design pays off: The GH4 lies perfectly in the hand, its relatively high operating weight of 865 grams therefore hardly disturbs.

However, the GH4 is not a beauty, its exterior makes it unmistakably clear: This camera is a working tool. The GH4’s chassis is made of lightweight, durable magnesium die-cast so that it can withstand the rigors of everyday photography. Panasonic has also sealed the top model against splash water. As with all splash-proof cameras, this also has a disadvantage: the fiddly rubber covers for the interfaces and buttons without a clearly defined pressure point. The rubber plugs for connecting the DMW-BGGH3 portrait format handle or the DMW-YAGH audio/video interface, which are not attached to the housing and are therefore easily lost, are particularly unkind.

The Panasonic Lumix DMC-GH4 has a pronounced handle and numerous control elements, as is customary for photographers. [Photo: Panasonic]

Apart from the fact that the buttons on the GH4 are very tiny, the camera is easy to operate. The luxurious mode dial, which can be locked against unintentional adjustment, certainly contributes to this. In addition, the GH4 offers an additional function dial for the drive mode, a switch for the AF mode and a whole series of function keys that can be assigned a function of your choice. The touch-sensitive touch display also makes operation much easier. Especially if it shows the current settings in Info mode and not the Live View image. Just touch the parameter and it can be adjusted. However, it gets confusing when you dive into the main menu. This is divided into long lists that occupy several screen pages. Often you have to scroll for a long time until you reach the desired entry.

Even though the display can be rotated and swivelled and is therefore easy to read in almost any camera position, you will usually look into the electronic viewfinder. It is almost as large as a 35mm DSLR and has an extremely fine resolution of 2.36 million pixels. Thanks to the OELD technology, the EVF even drums up the finest motif contrasts very finely; the desire for an optical viewfinder doesn’t even arise. Not to mention that an EVF displays much more information when needed than a DSLR viewfinder – such as a live histogram or an electronic spirit level. Thanks to the eye sensor, the GH4 automatically switches between EVF and display, the sensitivity of the sensor can be adjusted.

While the interfaces on the left side of the camera disappear under rubber plugs, Panasonic has provided the memory card compartment with a flap that closes tightly. The lid for the battery compartment on the underside is similarly elaborate. And because there’s plenty of room for the rechargeable battery in the large handle, the large energy dispenser can withstand 530 shots (measured according to CIPA). The tripod thread not only fits correctly in the optical axis, but is also far enough away from the battery cover – so the battery can be changed even when a quick-release plate is fitted.

Equipment

The Lumix GH4’s equipment range is so large that it’s better to think about what the camera doesn’t have to offer. Motive programs, for example, leave them out of the picture. In view of the target group to which the professional camera is directed, this is alright. For the quick snapshot in between, there is at least a fully automatic function that can even be overridden (of course conveniently via touchscreen). The GH4 also lacks a panorama automatic, but has an HDR automatic on board. Also included are 22 creative effects, which also work with video recordings.

Those who prefer to compose their own HDR photos from an exposure series will enjoy the very extensive bracketing functions. With the GH4 it’s easy to shoot five shots with an exposure distance of 1 EV – so many other manufacturers can cut off a target. Panasonic’s photo engineers seem to have worked closely with their video camera development colleagues on exposure metering. The GH4 comes with a zebra function that is commonplace with high-quality video cameras, but not with photo cameras. This function hatches a previously defined brightness range in the viewfinder image and immediately shows, for example, which areas of the image run the risk of being eroded.

The Lumix GH4 impressively underscores the fact that Panasonic is no newcomer to professional video recording: It was the first (and the only one during several years) system camera to film in 4K resolution. A single image with a maximum of 4,096 x 2,160 pixels is resolved – this corresponds to about eight megapixels! In addition: Smaller and lighter than the GH4 is currently no other camera with interchangeable lens that resolves 4K. No wonder that the GH4 was used as an ultra-HD camera for aerial photography from a quadcopter during the soccer World Cup in Brazil.

However, this miracle of resolution also has its hooks. As soon as the GH4 is switched to 4K mode, the maximum frame rate drops to 25 fps. That’s not a leg break in itself, 25 fps is roughly the frame rate at which movies are shown. What is annoying, however, is that the entire camera works in 4K mode with the handbrake applied: The viewfinder image jolts during pan shots and the AF focuses noticeably more comfortably (more on general AF performance in the “Lens” section). Video professionals won’t bother as much, they’ll manually adjust exposure and focus anyway. But amateurs will not only say goodbye to 4K recordings because of the slowed performance. But above all because they require extremely powerful hardware for playback and editing. In principle, it is possible to use Lightroom 5.4 to extract still images from 4K images. In the foreseeable future, many an event or sports photographer will simply record short video clips and then extract still images from them instead of waiting for the right moment to release them.

Even though the GH4’s 4K mode may not yet be fully developed in all respects, it films in full HD (1,920 x 1,080 pixels), the camera proves to be extremely powerful. The frame rate can then be increased up to 100 fps, enabling buttery 4x slow-motion playback at 25 fps. Unique also for a system camera: The GH4 generates image and sound signals as required in order to calibrate external recording devices. If desired, it outputs the video stream uncompressed via the HDMI output at a data rate of up to 200 Mbit/s!

But back to the photo functions. Panasonic has equipped the GH4 with a powerful on-board flash (LZ 12.5). If required, an external flash can be connected via the system shoe. There are no gaps in the flash functions, the GH4 has everything you could wish for, from the pre-flash to reduce red-eye, from long-term synchronisation to the second curtain to wireless control of system flash units.

The GH4’s series photo performance deserves respect. Not only does she sprint off at a breathtaking pace, but she also keeps it going for a very long time. But one thing at a time: If a continuous autofocus is omitted during continuous shooting, the GH4 takes 11.7 photos per second (fps) with JPEG shots, while the raw format still takes 11.0 fps.

She shows a remarkable stamina. The GH4 only runs out of breath after 169 JPEG and 41 RAW shots, respectively, and it falls into the more leisurely endurance run. This she completes with still considerable 2.6 fps in JPEG or 1.7 fps in raw recordings. But it’s also impressive how quickly the GH4 writes the fast shooting series to the memory card. Even after about half a minute of continuous fire, it only takes a few seconds until the indicator light goes out and the GH4 is ready to go again.

Continuous frame rates of 11 fps are only needed for really fast motifs. In this high-speed mode, the GH4 displays the last photo taken instead of the viewfinder image – this is a problem with pull-alongs. If you switch back one level to around 7 fps, the GH4 offers two more options: Now it can track the focus and displays a continuous viewfinder image that is only interrupted by the shutter for a very short time. This interruption is so short that it is actually only perceived as a darkening of the Live View image.

Panasonic has equipped the GH4 with a wealth of playback and editing features. Not only is it possible to develop raw recordings directly, the GH4 even offers rudimentary retouching functions. The WiFi functions of the GH4 have also matured. It has NFC on board for easy pairing with appropriate mobile devices, alternatively it offers to transfer the connection data to the mobile device via a QR code to be photographed from the display. By the way, the GH4 does without an energy-hungry GPS receiver; if required, it can obtain the location coordinates from a connected smartphone.

Lens

Currently, the Lumix GH4 is only available as a set with the tenfold zoom G Vario 14-140 mm F3.5-5.6 Asph. Power O.I.S. Power O.I.S. The lens has proved its worth in everyday use; the section on “Image quality” deals with the question of its imaging performance. The tube of the set lens is made of high-quality plastic, Panasonic has opted for metal for the bayonet connection. It is also equipped with an optical image stabilizer, which can be switched on and off with a switch on the lens.

Zooming is done in the conventional way, i.e. with a mechanical ring. The mechanism works precisely, but not completely silently – which can be annoying, especially when shooting movies. Motorzooms are generally better suited for zoom drives when filming. The focus system of the GH4 is highly developed and lightning fast.

For single shots, it takes a maximum of 0.2 seconds for the camera to focus from infinity to two meters and release. In practice, this means that the GH4 beeps practically instantly after you tap the trigger. The autofocus is not quite as fixed when it is used to adjust the focus for continuous shooting or filming.

Those who prefer to focus by hand will be actively supported by the GH4. The camera automatically displays a focus magnifier that magnifies about a quarter of the image. By default, this magnifying glass appears in the center of the viewfinder, but it can be moved to any position. It’s also nice that the GH4 is capable of focus peaking, contrasting edges in the focus plane are then marked in color. And that’s not all, the GH4 also displays a distance scale in the viewfinder image – more support for manual focusing is hardly conceivable.

Picture quality

With 4,608 x 3,456 pixels, the image sensor of the GH4 has the same nominal resolution as the converter of its predecessor. But Panasonic has completely redesigned the sensor, increasing the readout speed by 50 percent to 50 ms. This minimizes the rolling shutter effect, which, for example, distorts the wheels of a passing car into an oval during video recordings. The image converter is supported by a quad-core CPU, which takes care of the processing of the image signals.

A glance at the laboratory protocol immediately shows that the G Vario 14-140 mm F3.5-5.6 Asph. set lens is not necessarily the dream partner for the GH4. The tenfold zoom only resolves moderately high with at best about 40 line pairs per millimeter (lp/mm). “Best case” here means: in wide angle position. At the long telephoto end of 280 millimetres focal length (related to 35mm) the lens just passes the hurdle of 30 lp/mm, the image impression is correspondingly soft for telephoto shots. In addition, the lens has to struggle with a significant drop in resolution at the edge, in the wide-angle range the edge loss is almost 50 percent. At least Panasonic resists the temptation to compensate the resolution weakness by aggressive image processing – sharpness artifacts hardly play a role.

On the other hand, the performance of the sensor and the image processing are truly impressive. Although the GH4 does not exactly excel with an exorbitant signal-to-noise ratio, even at just under ISO 800 this falls below the critical limit of 35 dB. However, this is certainly also due to the fact that Panasonic has pleasingly cautiously tuned the noise reduction. On the one hand, this makes the luminance noise critical from ISO 1,600, but the texture sharpness remains high up to over ISO 3,200. In plain words: The GH4 preserves the finest details well even at high ISO numbers, but accepts somewhat more brightness noise. This is perfectly okay, as the noise is very fine grained up to the maximum sensitivity of ISO 25,600.

The GH4 does surprisingly well in terms of noise, given its rather small micro-four thirds sensor. This also applies to the input dynamics, which, apart from an outlier at ISO 1,600, are as high as ISO 3,200 at 10.5 EV. This advantage cannot be fully exploited, however, as the output dynamics drop sharply starting from the basic sensitivity and already reaches the critical limit of 128 brightness levels per colour channel at ISO 1,600. That’s what it means: The higher the ISO number, the more the GH4 loses the ability to reproduce even the finest tonal gradations.

The Lumix GH4 also doesn’t take it so exactly with the lifelike color reproduction. She has a clear preference for magenta and orange tones, which she strongly emphasizes. Especially the particularly critical skin tones suffer from this, and Panasonic is happy to make some improvements to the colour rendering.

Bottom line

In comparison to its predecessor, the GH4’s video capabilities were the main focus of Panasonic’s attention. It is the first system camera that can film in 4K resolution. A capability that is also interesting for photographers: Still images with a resolution of around 8 megapixels can easily be extracted from the high-resolution videos. But photographers benefit even more with the GH4. For example, by the very high serial frame rate, which she also endures for a long time. Or from lightning-fast autofocus, which focuses practically instantly. There’s nothing to criticize about the equipment of the GH4, which is clearly aimed at experienced photographers with its lack of motif programs. The GH4’s rugged camera body is large and heavy for a system camera, but fits snugly in the hand. Thanks to the many dedicated buttons and switches, but above all the touch-sensitive display, the operation is also not a cause for criticism. The set lens, on the other hand, has to endure this. The resolution of the tenfold zoom is at best mediocre, even weak at the edges. The image quality provided by the GH4 is quite different: Panasonic has tuned the noise suppression well, with hardly any details falling victim to it up to ISO 3,200. However, Panasonic could still refine the color rendering, even the GH4 emphasizes orange and magenta tones too strongly. The bottom line is that the GH4 offers everything you would expect from a professional system camera. And if the video functions are in the foreground, the Lumix GH4 is currently without competition.

Panasonic Lumix DMC-GH4 Datasheet