This is for better and for worse, of course. The camera has grown significantly in size over the GH2, but it also adds better ergonomics and more features. Whether this is good news for you, or bad news, depends on what you want from the camera. If you want a camera which has a good grip, and a good layout of buttons and control wheels, then the GH3 is for you.
On the other hand, if you came to the Micro Four Thirds system for the smallest camera with a good photography and video recording performance, then there are other cameras that may fit your needs better, e.g., the Panasonic G5 and G6 (announced April 2013) or the Olympus OM-D E-M5.
Panasonic GH2 (left) and GH3 (right)
Almost every aspect of the camera is improved, compared with the GH2. There are some exceptions to this, and let's look at them straight away: It no longer has an oversized multi aspect sensor, the EVF has different optics which is smaller, hence it is not as well suited for people who wear glasses. Also, some have reported bad sharpness and image smearing, although I have not seen this myself. There are also some features that are not as easily available through the Q menu or the function keys as before.
Beyond just improving upon the GH2, the GH3 also includes some fun new features, like Wifi and built in timelapse recording. It also has rotation sensors built in, meaning that it can support auto-rotating images that are not taken with OIS lenses (previous Panasonic cameras could not), and it can show water level type lines in the display, to help you keep the camera level.
The GH3 has a more hefty feel to it than the GH2. This is due to the increased weight, of course, but also due to other materials. The GH2 has a steel chassis with a plastic body around it. While I think this is a completely adequate construction for a small camera, others think that there should be more metal in a high end camera body. And the GH3 caters to these needs, as it adds a magnesium body construction.
Also, the control wheels and buttons feel higher quality than the GH2. When moving the wheels around, they have a more satisfying clicky feeling to them, indicating a durable premium construction.
While the GH2 has a lot of cheesy chrome details, the GH3 has changed these to matte black. This makes me quite happy, since I think the chrome shutter button, lens release button, and so on, were just stupid. This makes the GH3 look more professional.
Even if the camera is larger, it still fits inside the Lowepro Munich 100 camera bag, which I like to use when only bringing one lens.
Compared with the GH2, the GH3 not only adds more control wheels and buttons, it also reorganizes them. If you are used to the GH2, you need to acquire new routines. But the changes are generally good. For example, previously, the AF-mode selector was on the left shoulder, while now it has been moved to the rear, operable with the right thumb, much easier to use.
Generally, the camera is very customizable. There are some odd and negative changes, though. With the GH2, the Creative Movie exposure mode (P, A, S, M) could be set by using the Q-menu. With the GH3, though, the only way to do this is to use the touch screen, as far as I can see, which is a bit awkward when using the EVF. It can also be done by digging fairly deep into the menu.
Panasonic GH3 (front, left) and GH2 (rear, right)
In general, the GH3 is a pleasure to use, with the larger grip, and the very customizable controls.
The GH2 had horribly slow buffer flush speeds. The GH3 improves upon this significantly, and this is no longer any issue. I haven't measured the speed of clearing the buffer, as I don't see this as any problem any more.
The GH3 also packs a bigger and more powerful battery, and can keep shooting longer before needing a recharge. Third party spare batteries are available cheaply, and are completely adequate.
On the GH2, the distance between the memory card door and the card itself was small, making it hard to wedge out the card. The GH3 memory card door is much better designed:
Panasonic GH3 (left) and GH2 (right)
The responsiveness of the camera is not always good. Some times, I press a button, and nothing happens. Turns out that this was because the camera was busy with something I did a second ago or so. So you cannot always operate the camera as fast as you'd want, that is my impression. Also, when reviewing images and flipping between them, it takes some time before the information from the new picture pops up. The old picture's information is retained for a short while before the new info comes up.
Another issue, is the lag before getting a sharp image when zooming in while reviewing images (playback). When reviewing pictures taken in vertical orientation, there is a three second delay before you see the sharp image when zooming in to 16x. This happens in JPEG and RAW+JPEG modes, and is very annoying. In RAW mode, you are reviewing a low quality JPEG image only, which does not look good when zooming in to 16x.
Since about the second generation of MFT cameras, the still image autofocus performance has been more than fast enough for virtually all use. Perhaps with the exception of using the Lumix G 20mm f/1.7 pancake lens, which can some times be a bit slow, due to the combination of a thin Depth of Focus (DoF) and a traditional focus construction moving all the lens elements back and forth.
Here I compare the AF performance of the GH2 with the GH3 with some different lenses. The results are a bit unexpected, for example, the GH2 performs better in some cases. However, keep in mind that the GH3 had the firmware version 1.0 at the time of testing, and also that the focus is still very, very quick in these examples.
The real problem of mirrorless camera systems, though, is the AF-C, continuous autofocus performance, e.g., when tracking moving objects. DSLR systems, while larger in size, can use phase difference autofocus (PDAF) for much better focus tracking of moving subject. The Sony SLT systems, which can operate with the translucent mirror down, can even use PDAF during video recording.
I designed a test to evaluate the continuous autofocus performance during video recording between the GH2 and GH3 cameras. The test shows that the GH3 keeps the subject in focus about twice as often. In my example, both cameras read the sensor output 25 times per second, so the improvement must be due to better image processing. Or, perhaps, one or both of the cameras can read the sensor output between the video frames, for even better video AF performance, but this is speculation. Either way, it is clear that the GH3 achieves better AF during video recording, which is what this system needs.
Here is another test, which compares the focus performance with the Lumix G 14mm f/2.5 in a real life situation. It is clear that the GH3 is way better than the GH2 in this respect. I would say this is a revolution, and the GH3 may be the first Micro Four Thirds camera to make AF during video truly possible.
The test does not indicate the performance of the AF-C mode for still image use, for tracking of moving subjects. I don't use this feature frequently, and I have not compared the cameras head to head in this respect.
However, the GH3 has an ace up the sleeve in this respect: The sensor can read the image at 240 fps (frames per second) for the quickest autofocus performance. This is twice as fast as the GH2. However, the small print says that at the time of launch, this feature is only available when using the GH3 with the Lumix X 12-35mm f/2.8 or Lumix X 35-100mm f/2.8 pro zoom lenses. This feature, as well as the general improvement of the image processing, makes it reasonable to believe that the GH3 improves upon the AF-C performance of previous MFT cameras.
The GH2 improved the video quality of the GH1, however, I never felt completely happy with the colours of the GH2. The same goes for photographs. The good news, then, is that the GH3 generally gives much better colours and tone straight out of the camera. It also improves the high ISO performance. With the GH2, I felt I could use ISO up to 1600 fairly safely. Using the GH3, I think this limit has been increased to 3200.
Here is a comparison of the image quality at high ISO for the cameras GH1, GH2 and GH3. I think the GH3 image output at ISO 1600 is the best, having best colours and more details in the shadows.
One of the fun new features of the GH3 is the electronic shutter. This feature is also found in the Panasonic G5. Here, I have used a LEGO Technic contraption to measure the speed of the electronic shutter: It spends 1/10s to roll across the sensor, potentially creating a host of negative side effects.
The rolling shutter can also be used creatively. Here are a couple of examples:
|When holding the camera upside down, you can make passing cars lean forwards.||The vibrating string on this bass creates a sine-like pattern.|
In the beginning, I generally kept the camera in electronic shutter mode, except when I needed to use the flash, a shutter speed slower than 1s, or ISO above 1600. However, I grew tired of deleting pictures due to excessive rolling shutter effects, so I now generally use the mechanical shutter, except when I want the shutter to be quiet.
Here are some more examples of the rolling shutter effect, including banding effects when photographing indoor in fluorescent light.
The GH2 had a very good video quality, and I felt no need to apply the "firmware hack" to further improve it. In this test, I put the cameras head to head to examine the quality of the video output. We see that there are small changes. The GH3 handles rolling shutter slightly better, and has better colours, in my opinion. It also has somewhat better dynamic range, and better sharpness and more details at 1080p. Even when looking at footage on YouTube, which compresses the videos, I think that there is a noticeable performance difference between the GH2 and the GH3.
The big change, though, is the increase of the number of video modes available, and also the higher possible bitrate.
Like the predecessor GH2, the GH3 also includes the Extended Tele Conversion (ETC) feature. This increases the reach of the lens by about 2.5x, while still achieving full 1080p resolution. However, the noise performance is not as good, especially at high ISO. In the video below, you can also see that the noise performance in non-ETC mode (normal mode) is quite good even at high ISO.
The GH3 also adds the ISO 6400 option for video recording, which is very useful for recording concerts in dim light, fireworks, and so on. The GH3 can also record video at ISO 12800, using a strange trick that I describe here.
On the negative side, the GH3 is the first camera in the series which does not have the multi aspect, oversized sensor. Read the article linked to see how this affects the video mode.
While a lot of people have been saddened by the lack of the multi aspect sensor feature, it is important to remember that this is no common feature. In fact, this feature has only been seen on the Panasonic GH1 and GH2 cameras: No other system camera has it. On the other hand, many other system cameras use the APS-C sensor, in which there is a smaller difference between the full sensor and the 16:9 video crop.
Much has been said about the electronic viewfinder (EVF) of the GH3. Many have complained that it smears the image, and is generally useless. While the GH1 and GH2 appeared to have the same EVF optics, the GH3 has a different type of optics, and a smaller lens to look through. The images below were taken at the same enlargement:
For a person who wears glasses, this is bad news. The smaller opening makes it more difficult to see the whole image at the same time when using glasses. While I have had no issues with image smearing, like other people have complained about, I think the new EVF is less suited for glass wearers, and does not allow me to see the whole image at once. The image is very clear and sharp, though.
Compared with the GH2, the GH3 gets a long overdue increase of the display screen resolution. Still, at 614.000 pixels, it is lower than much of the competition. The screen appears much more clear, though, so this is good news. It uses OLED technology.
However, this still only corresponds to 480 pixel rows, meaning that it is not possible to use the LCD screen to fully assess the image sharpness when manually focusing during video recording at 1080p.
Just like all other Panasonic Micro Four Thirds cameras, the GH3 includes a built in flash. As you can see, it is not as tall as the one on the GH2, which is a strange development. Generally, the further from the lens mount, the better the flash works for general use.
Looking from above, though, the GH3 flash is located further to the front, which could be better for dispersing the light over the lens.
But, as one say, the proof of the pudding is in the eating, so let's see how they perform. In this test, I have placed the cameras about 1 meter from a wall, with the Lumix X 12-35mm f/2.8 at 12mm. The lens hood was mounted.
As you can see, even if the GH3 flash is lower, it still does a better job of avoiding the lens hood when illuminating the subject.
The camera adds a wifi mode. Setting up and using the mode is not as straight forward as it could have been, and the functions generally feel a bit immature. But being able to control the camera from a smart phone is a fun novelty, and also quite useful.
Compared with the Olympus OM-D E-M5
The Olympus OM-D E-M5 predated the GH3 by about half a year, and has been very successful. It has a retro metal construction, and the image quality has generally been praised. They probably share vital sensor components, although their filter and image processing probably differ. For example, the Olympus OM-D E-M5 is said to be quite sensitive to infrared light, while the GH3 is barely sensitive to infrared at all. This indicates that they have different filters in front of the sensors.
In general, I would say the GH3 has the best feature set and the best ergonomics. On the other hand, the E-M5 is a smaller camera, and it includes in-camera image stabilization (IBIS). Personally, I don't like the retro design of the Olympus OM-D E-M5. But I understand many are crazy about it. Also, I think the E-M5 is more awkward to hold and use, with no real grip. The wheels and buttons on the E-M5 appear to have been made to look cool, and not to function ergonomically, I think, however, I know this is a controversial issue.
There is little doubt that the GH3 is the best camera for video performance. For out of camera JPEG images, the OM-D E-M5 is probably the best. If you process the RAW images, then they are probably similar. Here you can read about how using RAW can be useful for improving your images.
I think the choice comes down to your preferences in terms of the design and ergonomics.
Compared with the Panasonic G6
The Panasonic G6 was announced in April 2013, almost half a year after the Panasonic GH3. Still, the GH3 is the better camera in virtually every way.
Not to say that the G6 is useless. Far from it. You may still be interested in the G6 for two reasons, mainly: It is smaller and lighter, and less expensive, while still packing most of the features of the Panasonic GH series.
It has a sensor from the GH2, however, with improved image processing. Sadly, it does not have the multi aspect sensor feature of the GH2.
In terms of video, it improves upon the GH2 features by adding 1080p resolution at 50/60fps (depending on PAL/NTSC), and also supports the extended tele conversion (ETC) mode.
When it comes to the design, it follows the GH3 trend by replacing chrome details with matte black. The overall shape bears a clear resemblance to the Leica R8 and R9, with elevated shoulders. While the camera is small, it has a generous grip, for better ergonomics.
This table sums up the size in comparison with the GH3:
Another good news is that the G6 is the first Micro Four Thirds camera to feature "focus peaking". This feature highlights strong edges in the display, making it easier to focus manually, e.g., during video recording.
A video optimized camera?
In online discussions, one often hear people referring to the GH3 as a video optimized camera, and stating that they would rather get a different camera for photography. So is the GH3 is video optimized camera?
I would say quite clearly not. The GH3 is a system camera with a very good video mode. But it is not video optimized. Truly video optimized cameras look quite differently. Video optimized camcorders like the Panasonic AF-AG 100 and the Sony NEX VG30 have a totally different form factor.
Also, if the GH3 is video optimized, why does it not include built in ND filters? And why does it not easily support video recording with a 180° shutter? In fact, in video mode, the camera does not even state which shutter speed it is using, except when using full manual mode. This is far from video optimized, in my opinion.
When looking at the GH3, it is rather clear to me what Panasonic is aiming for: The pro DSLR market. The camera mimics quite well professional cameras like the Canon 7D and the Nikon D800, with twin control dial, weather sealing and a rugged body. When seeing the new lenses that goes with it, this connection is even more clear. The Lumix X 12-35mm f/2.8 or Lumix X 35-100mm f/2.8 lenses correspond to the typical photojournalist pro zoom lenses.
The Panasonic GH3 is a great camera. It marks a new start for Panasonic, a journey into the realm of professional camera systems.
If you value the ergonomics and features, the GH3 is a very good choice.
At the same time, it loses some of the initial advantage of the Micro Four Thirds system: Size.
If you are looking for a more compact camera, you could consider the Panasonic G5, the predecessor Panasonic G6, or the Olympus OM-D E-M5. These do not have all the features of the GH3, but are still very good.