An important feature of the Panasonic GH1 and GH2 was the multi aspect, oversized sensor. They had sensors larger than that of the other Four Thirds sensor cameras. This allowed taking pictures in the aspect ratios 4:3, 3:2 and 16:9 with the same diagonal sensor length, and, hence, using the full image circle. This is in contrast with other Micro Four Thirds cameras, which apply sensor cropping at 3:2 and 16:9 aspect ratios.
When the Panasonic GH3 was launched late 2012, it was a big disappointment that it did not offer the multi aspect sensor feature of the two predecessors. But what does it mean?
The illustration below shows the two sensor sizes. The green rectangle is the standard Four Thirds sensor size, while the black corners outline the GH1 and GH2 sensor size. Since the GH3 has the standard sensor size, it crops to achieve 16:9 video recording (orange box). The GH1 and GH2, on the other hand could use the red rectangle for video recording, using the image circle more efficiently and also achieving a wider field of view given the same lens.
In video
In the illustration above, the GH3 video crop of the sensor (orange box) is 7.4% smaller than that of the GH1 and GH2 (red box), when measured by the diagonal. This means that when using one of the kit zoom lenses at the widest setting, 14mm, the diagonal field of view of the GH3 corresponds to 15mm in video mode. This was calculated as 14×(1+7.4%). So, as compared with the predecessor, the kit lenses will give you less wide angle when video recording.
What you can do, then, is to use a different lens. The Lumix X 12-35mm f/2.8 lens starts at 12mm, and hence, gives you a better wide angle during video. On the other hand, it has a more limited zoom range, stopping at 35mm, well before the typical portrait lens focal length of 42mm. It is an excellent lens, though, probably the best I have ever used.
Another option is the Olympus 12-50mm f/3.5-6.3 power zoom lens. While this lens generally gets mixed reviews, probably because of the limited maximum aperture, I think it is a very interesting lens. It is the only zoom lens to cover both the very wide and portrait lens focal length. On top of this, it also adds a macro mode and power zooming, as well as coming in a weather sealed constant length package. On the downside, though, it does not feature optical image stabilization, so using it for video recording on a Panasonic lens is going to be tough. Without a tripod or a good support, your videos risk being shaky.
It's good to keep in mind that the lack of a multi aspect sensor in the GH3 is nothing extraordinary. In fact, out of all video enabled consumer system cameras, the GH1 and GH2 were the only to feature the oversized multi aspect sensors. All other do not have this feature. On the other hand, most other video enabled system cameras have an APS-C sized 3:2 aspect sensor. When cropping such a sensor to 16:9 for video, this wastes a relatively smaller part of the sensor than when cropping a 4:3 sensor. Hence, the oversized sensor doesn't make that much sense with APS-C sensor. The illustration below shows this:
The Four Thirds sensor wastes 25% of the sensor area when cropping to video mode, and 7.4% of the image circle (diagonally). The APS-C, on the other hand, wastes only 16% of the sensor size, and 4.5% of the image circle. So the oversized sensor feature does not make as much sense with the more common APS-C sensor format.
Here is a side by side video showing the GH2 and GH3 in photo and video mode, both using the Lumix G 14mm f/2.5 pancake lens. It shows that when changing to video mode, the GH3 loses some field of view due to cropping the from the Four Thirds sized sensor:
In photography
If you like to take photos in the 4:3 aspect ratio, then there is no difference whatsoever between the GH2 and the GH3. The resolution is exactly the same.
However, the GH1 and GH2 had the option of using the 3:2 and 16:9 aspect ratios for photos as well, while still retaining the same diagonal field of view. If you intend to use the images in this format, then you would use the lens image circle more efficiently with these cameras, and the GH2 will give you better resolution to boot. Here is a comparison table:
Photo resolution
GH2
GH3
4:3
4608x3456 (16MP)
4608x3456 (16MP)
3:2
4752x3168 (15MP)
4608x3072 (14MP)
16:9
4976x2800 (14MP)
4608x2592 (11MP)
These differences are not that important, surely, but there is in fact a significant difference.
On the other hand, with a camera like the GH3, it is best to stick with the 4:3 format when photographing, and crop the image later, if needed. And that saves time and hassle while photographing, which is not the worst thing you could do. With the GH2, I would often change the aspect ratio when photographing something wide, giving me slightly better resolution. With the GH3, I just skip this part, which is easier anyway.
Conclusion
Losing the multi aspect sensor feature with the GH3 was a setback. However, the consequences are not that severe. You lose the very widest field of view in video mode. If you prefer using longer focal lengths, this might actually be an advantage.
Producing two sensor sizes was probably too costly for Panasonic. So I can understand their desire to standardize the sensor size from an economic point of view. The Panasonic G5 and Panasonic G6 cameras are said to have sensors based on that from the Panasonic GH2. However, they still do not have the multi aspect sensor feature.
In fact, Panasonic has done the same also in the compact camera market. Their LX3 and LX5 premium compact cameras featured a 1/1.63'' (8.07 x 5.56 mm) multi aspect sensor, larger than the typical 1/1.7'' sensor mostly found in these cameras. The newest Panasonic LX7 has a standard 1/1.7'' (7.44 x 5.58 mm) sensor, from Sony, incidentally. It still achieves the multi aspect feature by having a slightly smaller image circle. This also allows for the very impressive aperture rating of this camera, f/1.4-2.3.
I think losing the multi aspect rate sensor opens up the need for more wide zoom lenses. Only two lenses start at 12mm so far, the Lumix X 12-35mm f/2.8 and the Olympus 12-50mm f/3.5-6.3. The first of these is very good, but also very expensive, and a bit short. The second does not have OIS, and is hence not so useful for video on Panasonic cameras. With this in mind, I think that Panasonic should make a lens specified at something like 12-50mm f/2.8-4.5 with power zoom and OIS. That would be great for video use with the GH3.
However, there is a rumour that the GH3 can record video at one stop more, ISO 12800, by dialling in +3 in exposure compensation. So, is this true? The quick answer is: Yes. But it's a somewhat strange process. I'll take a look here.
In A (aperture priority) mode
What's going on is this: In the Creative Movie mode, A exposure mode, you set the aperture and the ISO, and the camera sets the shutter speed. When setting the ISO to the max, and then dialling in a positive exposure compensation, nothing happens until you reach +2. Then, you get one more stop of gain (light) until you reach +3. So, it might seem like the camera gives you one more stop of ISO for free.
But what you don't see is the shutter speed. I think it is a big problem with the GH3 that it does not state the shutter speed during video recording, except in full manual M mode. This makes the camera much more difficult to use for video recording.
However, for the moment, you can trust me that the camera tries to give you a 180° shutter in video mode, meaning that the shutter is open half the time, or a shutter speed of 1/50s if you are using a 25 fps video mode. Except if you dial in +3 exposure compensation, then it reverts to a 360° shutter, one full stop more exposure. You see this as a significant gain in brightness, if you are video recording in a too dim environment.
This can be easily demonstrated. See the video below in the next section.
In S (shutter priority) mode
Set in a similar setting, where the lightning is not enough at ISO 6400, full aperture, and 1/25s (or 1/30s for NTSC camera), when dialling in +3 exposure compensation, you get around one more stop of brightness, as compared with the maximum exposure in M mode.
Hence, it is true to say that you effectively get around ISO 12800 by using the Creative Movie mode in S (shutter priority) mode and dialling in +3. This only makes sense when the lightning is very dim. Otherwise, you simply get a very overexposed scene, which is not what you want.
Here is a video demonstrating the features of the A and S modes:
Here are also comparisons of the exposure levels in the video. From left to right, we have the A mode, M mode and S mode. We see that when using the Aperture Priority (A) mode with no compensation, it corresponds to 1/50s (180° shutter). When dialling in +3, though, it corresponds to 1/25s exposure (360° shutter). In S mode, though, we get around one stop more gain at +3 exposure compensation, effectively around ISO 12800:
Conclusion
The GH3 behaviour is a bit strange here. In A mode, it runs a 180° shutter by default, i.e., one stop less than the maximum exposure. Only when you dial in +3, you get the full exposure, one stop more. Specifying a 360° shutter manually in M mode gives exactly the same exposure, i.e., there is no "magical" extra sensitivity when dialling in +3.
The feature might still be useful. If it is too dark for ISO 6400, and you want the camera to use a shutter speed as slow as possible, you can set the exposure compensation to +3. You might find that easier than switching to the M exposure mode, where you could do the same.
In S mode, though, you can also dial in +3, and get one extra stop of gain, but at the same shutter speed. This appears to be a way to get around ISO 12800 in video mode. Note that this only works when the lens aperture is set to the maximum. Otherwise, the camera would rather first increase the aperture to achieve the exposure compensation, rather than increase the ISO sensitivity.
Alternative solution
If you are stuck in ISO 6400, maximum shutter speed (1/25s in 25fps or 1/30s in 30fps, depending on PAL/NTSC region), and you still need more exposure, what can you do? There is a solution, actually. There is another, semi-hidden feature of the GH3. It can record video at even slower shutter speeds, to capture more light in each frame.
For example, I recorded a video at 1/13s shutter speed at a concert, since I needed one stop more brightness even at ISO 6400. Of course, this gives you only 13 unique frames per second, even if the video stream is still 25fps. And you get significantly more motion blur, since each exposure is slower.
Here is a short description of how it was done, and a comparison between 1/25s and 1/13s. You must set the mode dial to "Creative Movie" mode, and then set manual focus, and the "M" exposure mode. Then you can set slow shutter speeds, all the way down to 1/2s. At 1/2s shutter speed, you only get two unique frames per second, of course, so the video might not be very useful.
As you see, 1/13s gives more exposure, and better brightness in the dim lightning, but more motion blur.
Here you can see the full concert videos as well. The one recorded at 1/13s:
And the one recorded at 1/25s, which is dimmer, but has less motion blur:
Both these videos were recorded using the Samyang 7.5mm f/3.5 fisheye lens. The maximum aperture is only f/3.5, which is quite small for a prime lens. On the other hand, it is normal for a fisheye lens. If I had used a lens with a larger aperture, for example the Lumix G 20mm f/1.7 pancake lens, I would not have needed to use a slow shutter speed.
The GF1 was the fist "rangefinder style" Panasonic camera. It had enthusiast friendly features, like a PASM mode dial, thumb control dial, plenty of buttons, and the possibility to attach an external viewfinder. Later, though, Panasonic seem to have had a hard time deciding what to do with the GF series. The GF2 and GF3 were all about making the camera as small as possible, sacrificing the enthusiast features like wheels, buttons and the flash hotshoe. The GF5 is quite similar to the GF3, but adds, e.g., a more ergonomic grip.
In April 2013, Panasonic are making a bit of a U-turn with the GF6, bringing it closer to the enthusiast camera territory where the series where born. It is no longer about being as small as possible, but grows a little bit while adding a useful tiltable touch LCD screen, and sees the return of the top mode dial. It also has a metal surface top plate, which I think looks a bit cheesy, but I think many will love it.
It has sensibly shaped grip surfaces for the thumb (rear) and middle finger (front), making it much easier to hold than the smooth GF3.
The GF6 has a sensor inherited from the Panasonic GX1, which should give you a good image and video quality.
It comes with the new Lumix G 14-42mm f/3.5-5.6 II kit zoom lens, which is getting good reviews so far, being smaller and lighter than the predecessor.
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. Even if the GH2 sensor on which the G6 is based is old, the updated processing adds a lot to the image quality. So you should still expect a good quality increase from 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:
Camera
GH3
G6
Width
133mm
122mm
Height
93mm
85mm
Depth
82mm
71mm
Weight
550g
390g
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.
With this in mind, it makes me happy that Panasonic is now updating this lens. The new lens has better aperture specifications, about a third stop better in the wide end, and a sixth stop better in the long end.
The new lens is also smaller, and has a front lens thread of 58mm, rather than 67mm for the old lens. With the experience Panasonic has acquired since making the original lens, e.g., from making the excellent Lumix X 12-35mm f/2.8, I'm sure they can do a much better job this time. If you have the choice, I suggest getting the newer lens.
Some might miss a motorized zoom. After all, if this is really a video optimized lens, why is the zooming done with a manual, mechanical ring? Zooming smoothly during video is almost impossible with a manual zoom ring. Most likely, a motorized zoom would be too complicated for such a lens. The motor would need to be very powerful, to be able to extend the duo cam front part of the lens.
Also, I expect this lens to have a pretty well dampened zoom ring. The Lumix X 12-35mm f/2.8 sure does, making it possible to zoom quite smoothly even during video. Unlike the basic kit zooms, which have a quite sticky zoom ring.
Olympus E-P5
The camera was announced on May 10th, together with a new external electronic viewfinder, the VF-4.
The camera inherits a lot of interesting and attractive features from the Olympus OM-D E-M5: It gets a tiltable LCD display, the new five axis image stabilization, now with automatic panning detection. Also, it gets dual control wheels near the shutter button. Using Panasonic lenses with OIS becomes easier, since the camera allows you to choose more easily if you want to use the in camera image stabilization (IBIS) or OIS.
As for the sensor, it is also the same as in the OM-D E-M5, which is good, since it has been hailed for the good image quality. You can take up to 9 frames per second in continuous shooting mode, although only 5 fps with autofocus enabled. For more easy manual focus with legacy lenses or during video capture, there is a "focus peaking" feature to assist you by highlighting sharp edges.
I think it is good that the flagship PEN style camera now comes with a tilting LCD screen. That is very useful. On the other hand, I think the lack of a built in viewfinder makes it less attractive. On the other hand, quite some people like using cameras without eye level viewfinders, so I guess it still makes sense from a market perspective. All in all, this is a modern camera with virtually all the features you could think of, in a somewhat classic retro design.
Blackmagic Pocket Cinema Camera
There is little doubt that, at the moment, the best Micro Four Thirds camera is the Panasonic GH3. However, the most interesting might very well be the odd Blackmagic Pocket Cinema Camera:
Not to say that everybody should rush out to buy this camera: Far from it. This is a very specialized camera. It does not take pictures, only video. And the video resolution is 1920x1080, nothing special at all.
However, since it is made for video, it has an imaging sensor optimized for video recording only, not photos. Hence, it is able to achieve much better video quality, especially in terms of dynamic range, handling of moire, and colours. It also supports higher bitrates, giving you less compressed video files.
Unlike the predecessor, the Blackmagic Cinema Camera, which also came with a Micro Four Thirds mount, the pocket version has an active mount. This is a very crucial difference. With a passive mount, i.e., no electronic communication, most Micro Four Thirds lenses are useless on the camera, as you are not able to change the focus or the aperture.
The active mount of the pocket version makes all Micro Four Thirds lenses usable, though. You can operate the aperture and the focus, and OIS even works on the lenses that have OIS built in.
The Panasonic GH3 handles autofocus during video capture surprisingly well, as I have demonstrated here. Even if the Blackmagic Pocket Cinema Camera features autofocus, you should not expect such a performance. Rather, you must probably rely on focusing manually during video capture, and there is a focus peaking mode to assist you.
On the negative side, the camera has a significantly smaller sensor that Four Thirds size. There is a crop factor of 2.88. This means that the Lumix G 14mm f/2.5 becomes a 40mm equivalent lens, i.e., a short normal lens. Finding a good wide angle lens might be difficult.
This is a camera for video enthusiast, who want the best video quality in a compact and relatively ergonomic package.
After the release of the two Blackmagic Cinema cameras, Magic Lantern have announced that they will make available firmware upgrades for the Canon EOS 5D MkIII. The upgrades enables RAW video recording at 24fps, at 14 bits depth, suitable for movie makers. The firmware also adds other features like larger resolution videos, 2.5K, 3K, 3.6K and other sizes.
What's even more impressive, is that the features are expected to be ported to the Canon EOS 6D, Canon EOS 5D MkII and Canon EOS 600D cameras! This firmware development may well remove a significant part of the market for the Blackmagic Cinema cameras.
28mm APS-C compact cameras
Within the last months, we have seen two new cameras in the somewhat thinly populated class of large sensor compact cameras. This market segment has previously been pioneered by Sigma with their strange and quirky DP series. Fujifilm were the first to get a good impact here, with the retro design 35mm (equivalent) Fujifilm X100.
Nikon and Ricoh now want a place in this segment as well, with the Nikon Coolpix A and Ricoh GR:
Both feature retractable lenses with a 28mm equivalent field of view, and an aperture of f/2.8. What's more, it is reasonable to believe that both feature the same APS-C sensor from Sony. The APS-C sized sensors are commonly used in consumer DSLR cameras.
The Ricoh camera is slightly wider, but slimmer and lower, and also lighter. They have similar features, and the choice largely comes down to what type of ergonomics you like. Beyond that, the Ricoh GR also packs built in ND-filter, which is useful for large aperture shooting outdoor in sunlight. It also comes with a significantly lower price tag. It appears that Nikon want to capitalize on their strong brand name by charging a premium price for their camera.
Given that one would often want a camera like this to be slim and fit in a pocket, I think the Ricoh version looks the most useful. The Ricoh also appears to have the upper hand in terms of optical performance, based on the tests I have seen so far.
Neither of the cameras have a tiltable LCD or the possibility to attach an external EVF, which is too bad, but hardly unexpected since they are intended to be compact and rigid.
When the Panasonic GH1 was announced in April 2009, it had a unique selling point: It was the first and only consumer system camera which could autofocus continuously while recording videos. Since this time, the competition has improved a lot, of course, and all mirrorless system cameras can autofocus while recording videos. But they use different technologies, and the performance varies.
The Panasonic GH3 was released with a claim to have the best AF performance of mirrorless cameras ever, as usual for a new premium mirrorless camera. And the AF performance for single still images is very impressive indeed. However, this doesn't really matter. All current Micro Four Thirds camera focus more than fast enough for static still images. Except possibly with the Lumix G 20mm f/1.7 pancake lens, due to its combination of a fast aperture and an old school focus construction.
What's still a challenge, though, is continuous autofocus during video recording, and focus tracking of moving subjects, in AF-C mode.
The Sony SLT cameras solve this by using a fixed translucent mirror, which means being able to use phase difference autofocus (PDAF) also during video recording. This system is able to track moving subjects very well during video, due to the genuine SLR PDAF technology. However, the cameras are not mirrorless, being DSLR systems with fixed mirrors, which means having larger camera bodies, and, usually, larger lenses as well.
The Nikon 1 system and Canon EOS M system solve this by having on-chip PDAF sensors, directly on the imaging sensor. With this technology, they can combine PDAF and CDAF, however, the real world benefits of this system are still undecided.
Panasonic and Olympus have so far used pure CDAF, with no specialized hardware to aid the focusing. They rather rely on image processing to speed up the autofocus. With the Panasonic GH3 being the most recent premium model, let's see if it actually does improve upon the predecessor GH2. To test the cameras head to head, I mounted both on a plank using Manfrotto Superclamps:
Here are the results in terms of autofocus performance during video recording:
As we see, the Panasonic GH3 performs much better than the GH2 in term of autofocus. Even with the same basic technology, the GH3 has a better image processing capability, which enables it to focus better while recording videos.
Notice that the GH2 needs to jog the focus back and forth to confirm the focus and settle. This is a typical sign of CDAF focus technology. The GH3, on the other hand, appears to nail the focus straight away, as if it was using PDAF. Which it doesn't.
I think it looks like the GH3 is a revolution when it comes to continuous AF during video for Micro Four Thirds. It may be the first camera to make AF during video truly possible.
And this does work well in real life situations. Here, I have recorded a concert using the Olympus 45mm f/1.8 at f/2, ISO 3200. The light was very dim, around EV2. The autofocus was left on during the video, and it generally keeps the image well in focus. In my experience, the GH2 would not have handled such a situation well:
Keep in mind that AF-C while photographing moving subjects is a totally different subject. I would expect the Panasonic GH3 to perform better here as well, as it is capable of AF sampling at up to 240fps with the most recent lenses, the Lumix X 12-35mm f/2.8 and Lumix X 35-100mm f/2.8. However, I have not tested this feature yet.
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.
Physical
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.
In use
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.
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)
Autofocus
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.
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.
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.
Photography
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.
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.
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.
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.
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.
EVF
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:
GH2
GH3
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.
Display
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.
Flash
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.
GH2
GH3
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.
Wifi
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.
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.
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.
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:
Camera
GH3
G6
Width
133mm
122mm
Height
93mm
85mm
Depth
82mm
71mm
Weight
550g
390g
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.
Conclusion
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.
A spare battery for a digital camera is a good thing to have. If the battery runs out, the only way to charge it would be to remove it from the camera and place it in the charger, provided you are somewhere with a power outlet. This means not being able to shoot for an hour, at least.
If you carry a spare, charged battery with you, you can just exchange the battery in a matter of seconds, and be ready to shoot again. However, original batteries often cost a lot. The GH3 battery can easily cost US$80 new.
With the GH3, though, third party batteries are available cheaply, and they let the camera see how much juice is left. So, from the point of not losing data when running out of juice, they are safe to use. Just like when using original batteries, the camera will warn you that the battery power is low. And, eventually, the camera will stop video recording and write the data to the memory card before shutting down.
The battery I tested is marked with "FOR BLF19", indicating that it replaces the original battery called Panasonic DMW-BLF19. Just like the original battery, it is marked with 1860mAh, i.e., the same power reserve.
Here it is next to the original battery, original to the right:
The third party battery feels a bit lighter, but otherwise they appear to be identical.
I have not formally tested if they carry the same amount of power reserve, but so far, the third party battery appears to be as capable.
The third party battery is a good alternative to the original version. It appears to perform as well, and is good to have in the camera bag as a replacement power, for the times when you need it. At the low cost, I would recommend getting a second battery for spare power.
When new camera generations get launched, everybody expect the high ISO image quality to improve over the previous generations. While we would use a low ISO as possible at all times some years ago, it is generally quite safe to use ISO 800 with newer generation cameras. Let's take a look at how the Panasonic GH series handles high ISO.
To test this feature, I rigged the Panasonic GH1, GH2 and GH3 on a tripod, using the Sigma 30mm f/2.8. I left the lens wide open, it tends to be quite sharp. To be able to compare the cameras, I set both in the Shutter speed priority mode (S), at 1/10s and auto-ISO. The camera would then select the ISO needed for the exposure to be sufficient. I used Auto White Balance (AWB).
These are the out of camera JPEG images, with standard image settings. The histogram below shows that all cameras expose the scene pretty similarly. The GH3 exposes it a bit brighter, though:
Another thing to note is that the GH1 uses the lowest ISO value of the three, 1250. This confirms again that the Panasonic GH1 had a somewhat conservative ISO scale, compared with other Micro Four Thirds cameras.
Looking at the image quality, we can compare 100% crops from all three images. I rescaled the GH1 image, to make it comparable with the 16MP output of the other cameras.
I think we can see that the GH2 images look sharper, but at the expense of shadow details. The GH3 appears to give a higher dynamic range, with more usable details in the dark parts of the image. With the advances of high ISO image quality, I feel quite confident using ISO values of 1600, and even 3200 when needed, with the Panasonic GH3.
When Panasonic released the GH3, it was expected to raise the bar even further in terms of video quality. To compare it against the GH2, I connected both cameras to a piece of wood, using Manfrotto Superclamps, so that they would record the same scenery for comparison.
On both cameras, I used the Lumix G 14mm f/2.5 pancake lens, a favourite of mine. I focused on "infinity", and then set both cameras to manual focus. The lenses were set to f/5.6 for the best sharpness, and I used the base ISO on both cameras. With the ambient lighting, the shutter speed was usually around 1/120s. Both cameras had the same settings in terms of sharpening and saturation. It was all recorded in 1080p, 25fps.
Here are the videos combined, for easy comparison:
Some may doubt that the quality of the YouTube rendering of the video is sufficient to really tell the difference between the cameras. I agree with that, and to assist in comparison, I uploaded parts of the video at 200% size, which probably makes the video image quality easier to assess. And I made some 100% crops from the original out of camera video files, uncompressed in PNG format below:
This last image comparison is from the ISO 1600 footage:
Conclusion
Just like I have concluded previously, the GH3 features somewhat less rolling shutter artefacts in video mode. Further, I think it looks like the GH3 handles high contrast better, and the overall sharpness of the video stream is better. Not unexpected, since the GH3 can record at up to 72Mbps bitrate, as compared with 24Mbps for the GH2. I used 50Mbps with the GH3 here, though. Of course, the bitrate is not everything, the sensor, AA filter, downsampling algorihm and compression algorithm are also important.
I also like the colours of the GH3 better. At high ISO, the GH3 does provide more details.
As far as I can see, the GH3 does deliver on the promise of delivering even better video quality than the predecessor GH2.
