This GH4 will have a lot to recommend it:
- Improved Viewfinder and rear display
- Improved focusing
- Faster processing
- Faster 1/8000th of a second shutter speed
- Faster 1/250th of a second flash sync
- Enhanced dynamic range at low(er) ISO sensitivity
- Panasonic lens profiles, similar to FujiFilm X-E2 and Olympus E-M1
- Better for current HD video
- Addition of 4K/Cinema 4K video
My biggest problem with the GH3 is when I'm using sunglasses with the viewfinder. I occasionally end up with a black display, which makes "best guess" my operational mode. The EVF (Electronic Viewfinder) on the Olympus E-M1 took care of all that (it does it too, on occasion), and I can assume (I've used it for a few minutes and it was good) that the FujiFilm X-T1 viewfinder is even better, due to raves I've seen about it so far. However, the 0.67x magnification (as compared to a 135 format dSLR like the Nikon D4) is not entirely impressive, as the E-M1 using 0.71x and the X-T1 has 0.77x, as I recall. I hope it's better than expected, and that it's not just an eye cup and an increased (10,000:1) contrast ratio providing most of the enhancement. I'm sure the EVF of the E-M1 (or X-T1) is rather expensive, but with everything else they've enhanced, I'd hope that Panasonic would want to create a great shooting experience. We'll see. (Update: "DSLRmagazine (translation here) met Panasonic chief engineer Inoue. He confirmed the GH4 EVF is a lot better than the one used by the GH3 and that has been also achieved thanks of the use of aspherical lenses on the EVF."--it sounds much better.)
The Face Recognition/Eye Detection auto focus enhancements sound as though they'll likely simplify my work (as long as it works correctly), since taking photos of basketball, cross country, or other sports requires me to get at least one face in focus. They've increased the number of focus points from 23 to 49, and you apparently have the ability to customize which you'd like to use as a pattern. Supposedly, the focus point can be anywhere across the frame, but if there are only 49 points, how can that be?
Depth of Defocus technology should speed up accurate focusing by comparing the distance from correct focus, using specific lens information. Whatever it takes to improve the sometimes laggy "world's fastest" (everyone has the world's fastest AF now) auto focus will be appreciated. Using lens profiles within the camera is something already being done by the Olympus E-M1 and FujiFilm X-E2 and X-T1. They've said that this sort of technology eschews the need for Phase Detect pixels on the sensor. I'm not so sure, but compared to Olympus' (supplier's) half-hearted design attempt in the E-M1, we shall see. The 35 pixels (areas? The X-T1 is using 86,000 PD pixels) used for phase detection weren't exactly a lot, but I think it's more about the cost than the number of pixels.
The improved burst speed is quite stunning--12 (twice as many as the GH3) frames per second, "up to approx.40 (including RAW)". I'm assuming that means that the raw buffer will hold 40 frames. The poorly translated press release needs some work. They're claiming 7 (4.2 on the GH3) frames per second in continuous/predictive auto focus, which is higher than single AF on the GH3, which is 6. I haven't counted on the continuous auto focus because the GH3's predictions were wrong for my shooting, so hopefully, that of the GH4 will be closer, or I will get a faster response from the single AF.
They've increased the standard top end of the ISO sensitivity to 25,600 from 12,800 because they've found a way to handle chromatic noise better. Given that I only use photos from the GH3 up to ISO 3200 on a regular basis, this could allow me to regularly use images at ISO 6400 and give my ISO 3200 photos an extra distance from extreme correction. I would generally not condone using ISO 3200 but photographing sports in a gym or at a swimming pool leads to a lot of bad lighting. In some cases, flash is permissible but my regular flash (Olympus FL-50) was damaged and is no longer functional and I don't care to spend money on another at the moment. ISO 3200 on the GH3 seems to be a bit rougher than on the Olympus E-M5 (but not the E-M1 supposedly), but then, it's also rougher than the newer Panasonic bodies, the GX7 and GM1. Then again, when the E-M5 was new, there were allegations that the ISO sensitivity numbers were higher than the actual sensitivity.
As with the enhanced processing, the dynamic range has been enhanced ⅓ EV at base ISO, which should be ISO 200 (but is apparently an extended ISO 100). Is it enough to stave off the Blackmagic Pocket Cinema Camera's great dynamic range? Also, has the dynamic range been enhanced due to moving noise producing electronics away from the sensor, or has it been enhanced with better, cleaner processing? (Given that I've seen the enhanced dynamic range at ISO 100, rather than ISO 125 even, I think they've re-worked their curves to emulate ISO 100 while actually using ISO 200, something many camera makers do.)
They've increased the fastest speed of the shutter to 1/8000th of a second and improved the flash sync speed to 1/250th of a second. Working with their newest 42.5mm f/1.2 lens should be much easier in bright light, along with those Voigtländer lenses at f/0.95. On the E-5, I'm above 1/4000th occasionally, so this will be of use to me on the GH4. The shutter durability has been doubled to 200,000 uses, which is higher than Olympus' E-1, E-3, or E-5 at 150,000.
They've increased the readout speed of the sensor to reduce/suppress the rolling shutter/jello effect during video. Obviously, no global shutter technology yet. My understanding is that you'll have to spend significantly more to get devices with global shutter technology.
Of course, their big announcement for video is that they have 4K and Cinema 4K resolutions available. They've also increased the upper bit rate for HD video from 72 Mbps to 200 Mbps. I am not a video person in general, so I can't say much about these. They've gone to a lot of trouble to allow the sensor to continue for longer periods of time without overheating. In fact, they have a mode where you can use a GH4 without recording at all, but to feed an external recorder using a higher specification than can be put onto an SD card, via the HDMI port or the new interface module that connects below it.
However, they have a new adapter module: DMW-YAGH interface unit for professional applications. This provides the inputs and outputs to make things work more easily, and enables a channel to record 4:2:2. It would also be useful, if you had several GH4 bodies and needed to use them interchangeably on one cart, but still allow them to be mobile. The GH4 body is somewhat different than the GH3 but still uses the same battery grip.
If I said that I was enthusiastic about this announcement, it would be an understatement. I found the GH3 to be a useful camera body, with a number of flaws. The company seems to have taken steps to correct the flaws while leaving the general design of the camera body as it was. Given the reviews and output from the company's GX7 body, I was expecting quite a bit more from a GH3 replacement. It seems that they've delivered. I hope that I still feel that way when I have one in my hands for a few hours.
What they haven't mentioned are the price and delivery dates. The rumor was under US$2000, which could easily be US$1999.99. Still, it will be less expensive than the Canon 5DMkIII, which they're targeting. Pre-orders are apparently available, starting on March 17th, so by then, they'll have finalized pricing, and will have an idea when they'll be able to finalize the firmware and ship bodies.
I wonder if there will be a long line, as there was with the GH3. It took quite a few months before there was a considerable quantity available, though Panasonic often struggles to provide products other than rice cookers and home phones.
Update 2014.02.23: This week, I went to buy a micro Four-Thirds lens, the Olympus 12-40mm f/2.8. While talking with the salesperson, I had some thoughts about the GH4 and the FujiFilm X-T1, along with what he was saying about delivery of lenses. Given that product manufacturing can be fraught with disaster and products can be delayed in being delivered to market, The GH4 seems the best product for me, even if the finer points of resolution of still photos isn't as good.
I'm not exactly in a rush. The GH3 does okay in low light. It's just not great. If the GH4 is one stop better, that's a great step. I've been looking for that perfect sports camera body, and the Nikon D4 might be that but not for me, not now. If I was making US$250,000 each year, why not? Besides, the hybrid abilities of the GH3 and GH4 are the reason I chose the GH3 anyway.
I was not extremely comfortable with the color from the Panasonic 35-100mm f/2.8 lens, but I'm hoping that the Olympus 40-150mm f/2.8 lens will be available later in the year, and while it's no Olympus 50-200mm f/2.8-3.5, it still has almost 4x zoom and the constant aperture will help. It may be enough for cross country running.
I was hoping that the GH4 sensor would have Phase Detection auto focus available, but Panasonic have said that they found the performance increase to be more important. Given my experience with Four-Thirds lenses on the GH3, if the GH4 AF performance with them is much faster, they might be as usable as on the E-M1, which wasn't as great as Olympus would like us to believe, at least, in my hands-on experience.
Update 2014.03.06: I saw this JPEG ISO sensitivity comparison. It doesn't look as though it's a complete win, but it's better with the GH4. Since I use photographs at ISO 3200, I'm interested in photos at ISO 6400. There was improvement in the face, but not so much in the hands in the shadow areas. I also thought that the face with the GH4 at ISO 6400 was an improvement over the GH3 at ISO 3200. Since raw file conversion is not yet available, I won't hold my breath to see if it's the truth or a trick, but I expect that it's the truth. Panasonic make good improvements in each generation of their processing.
I was reading this review of the X-T1 at Admiring Light. It confirmed more of the quirks that would make it difficult for me to enjoy using it for sports. So, if the GH4 doesn't cost a small fortune, it looks as though there is only one way to go for what I do.
Update 2014.03.08: Would US$1699.99 be too high a price? It seems as though Panasonic is still trying to figure this out with only a week or so left for pre-orders to be allowed. Obviously, it's a fine line with the perception that the E-M1 and X-T1 are equals, even though their video capabilities are inferior. It won't matter to those companies for which the GH4 will be one of many tools in the shed, but for the hobbyist, it's a major sticking point. Besides that, Panasonic has a routine about pricing too high, and then, discounting too quickly, making early adopters upset.
I have expected anything up to US$1999.99 but US$1499.99 would be extremely reasonable. I don't see it lower than that, at least, until its replacement is ready to arrive on the market.
Update 2014.03.16: The US$1699.99 became a reality. That's not horrible at US$400 more. It is a better product with increased functionality. The processing power alone adds to the price quite a bit. I was a bit shocked at the price of the DMW-YAGH interface unit at US$1999.99. It must have extremely noise-free pathways to be so expensive. For a studio to buy it, I'm sure it would not be a huge purchase, and it will work with multiple GH4 bodies. However, at $3299.99 for the pair, it shouldn't bother most people serious about film making.
I would say that the GH4 is a no brainer, but it's not an impulse item like chewing gum or mints. If the GH4 is as good as the E-M1 or the X-T1 for stills, I think Olympus and FujiFilm will have a fight on their hands because video is not something either company does well. Similarly, the Nikon D7100 and Canon 70D and 7D are targets for Panasonic and they don't do video well.
Update 2014.03.20: I was watching a discussion on Vimeo between Zacuto Films and a Panasonic representative who apparently knows the motion picture technical side quite well. While you cannot record 4K 4:2:2 video directly to the SD Card, you can use either the HDMI output or the YAGH interface unit to do that, and you'll need to interface with an external recorder. Something that The Camera Store brought up in their video on YouTube is that the YAGH interface is unpowered--there is no battery. Therefore, you need to carry a battery with you to do handheld work, or you work close to an electrical outlet. For US$1999.99, shouldn't there be a battery inside it? I don't suspect most people in the business will be bothered, or will be using it handheld but who knows? My ignorance of the motion picture industry counts here. On both videos were mention of video and motion picture related options in the GH4, so that it would be easier to work with familiar measurements, rather than ISO sensitivity, for example. Apparently, a lot of these options were available in the AG-AF100/AF105 micro Four-Thirds camcorders. That means that the GH4 is a lot of power and ability at a very comfortable price, even at US$3299.99 with the interface unit. Supposedly the next least expensive, similarly available product/combo would be something from Sony at around US$25,000.
I was glad to hear that the stills ability has improved, but sad that the viewfinder is still a bit odd optically. It certainly dampens my enthusiasm for using it. However, any improvement is great because the GH3 viewfinder is a pain for me. The Camera Store video mentioned that the shutter noise is louder, but the enhancements seem worth it, especially the durability and doubled frame rate in single auto focus.
Update 2014.12.01: I got my GH4 about a week ago, and at a $200 discount. It just feels right, as did the GH3. It's very close to the Olympus E-5 dSLR in shape, but with a more Canon feel than Nikon, though it still uses PASM instead of Tv for S, Av for A, etc.
The viewfinder is better. I don't believe I've had it black out yet but I have a feeling it has to do with the proximity sensor in the GH3 and the E-M1. Last week, when I was using the E-M1, I had a black out but I somehow saw the image below on the rear display. On the GH3, I never had the display facing out, so I never would have known.
The performance seemed good but not amazing--it is shipped with Continuous Auto Focus enabled. Auto Review is also enabled, which not only slows things down, as it does with the GH3, but it's a battery waster--something that also seems consumer-oriented. Are consumers the target buyers for the GH4?
Since the price of the GH3 has dropped below US$1000, it may be a more difficult choice to buy the GH4. I suspect it's a very, very good choice, though.
Update 2015.01.03: After a couple of thousand photos--no, serious--a couple of thousand photos, and over 100 video clips, I'm feeling fairly secure about the GH4. However, I wish that they had a !@#$ profile for the Olympus 12-40mm f/2.8 lens. I've found too many photos that weren't in focus, although video seems fine for the most part. I'm sure there is firmware to be released. I think they'll be refining firmware for a while. I really wish that they would support significant Olympus lenses. Surely, it would be to Panasonic's advantage to support Olympus lenses in Depth From Defocus.
If I was making a film, I don't think it would matter. Manual focus lenses aren't a problem in film-making but I'm a sports photographer. However, until late 2011, I'd never used auto focus for much more than testing. I'd always manually focused for sports. The problem for me now is that micro Four-Thirds lenses are too small. I've tried manually focusing the Panasonic 35-100mm f/2.8 multiple times without any repeatable success. I was having a problem recently where the GH4 was focusing on the fence behind the rider, similar to the GH3 focusing on a fence behind the runners. Back then, the magnified view got in my way. It's not bad with the GH4, though. I can see around it.
Still, I'm wondering if I should buy the Panasonic 12-35mm f/2.8 lens. I waited too long to get a holiday discount, but it seems permanently at US$999.99 now. I'd rather spend money on the Metabones SpeedBooster adapter and Sigma 18-35mm f/1.8 lens combination, which would be big enough to focus manually. It's too bad the Metabones SpeedBooster for Nikon G lenses doesn't have a focus confirmation chip, at least, that I can find.
Update 2016.01.17: It's been over one year and I've taken over 62,000 photos and made over 120 videos from many more video clips with the GH4.
When I arrive at a skate park, I reach for the GH4 first, ahead of the Olympus E-M1 or my recently-purchased GX8 or any of the dSLRs.
I've been using it with various lenses, including the Olympus 12-40mm f/2.8 and Panasonic 35-100mm f/2.8. The Leica/Panasonic 15mm f/1.7 has been extremely useful in lower light situations, as has the Olympus 8mm f/1.8 fisheye lens. I even bought the Panasonic 12-35mm f/2.8 lens with the GX8 with a healthy discount.
The GH4 still picks the fence behind people, so no matter the AF enhancements, Panasonic has a long way to go. Face detection works, but so slowly that it's not really usable. It's slightly faster on the GX8 but it only takes a quick try with the Olympus E-M1 to see how great Olympus' implementation of face detection is.
There have been occasions when I was frustrated with the GH4 but I get more done with it and it feels more like an extension of my hand than any other camera body since the Olympus E-1.
Battery life is amazing and the viewfinder is almost always amazing. On occasion, it blacks out, due to the angle with my sunglasses, but it works very well overall. I've had the same problem with the E-M1 and the GX8. It seemed as though the GH3's viewfinder was blacked out more than it was useful.
I can't say that the image quality is amazing in lower light, but it is manageable and the camera is responsive in conditions that cause the Nikon D7200 to stop and think...and think...and think. I don't use images past ISO sensitivity of 3200, even though the top end of the normal range is 25,600. Video seems better at that sensitivity but it's using a smaller resolution, even for 4K resolutions, which I don't really use.