In this review, I'll make occasional mention to the GH2 which I used to have and the Fujifilm X-Pro1 which I also use.
- BUILD QUALITY -
GH3 is built like a top quality APSC DSLR except in a slightly smaller size. It's 550g body alone with batteries. Just for comparison, Canon 7D is 915g with batteries. Compared to the GH2, GH3 is big. When I first held it, I was wondering if it's really a Micro Four Thirds camera. It looks like it could fit an APSC lens -- X-Pro1's almost the same size without the grip and flash hump.
The body is hard. Hand grip is comfortable. Buttons are easy to press. Dial wheels are nice to turn. I love the two dial wheels. The overall ergonomics is one reason why I upgrade.
Major bummer for me is the battery cover which is too loose and will open with just a gentle brush against it. It has opened accidentally many times for me.
- EVF -
It's slightly smaller than the GH2 and I'm still trying to get used to it after weeks.
There are reviews online complaining about the smearing EVF at the edges. It happens to me too. I'm wearing spectacles. You have to place your eye exactly in the centre to get everything clear. You know the plastic in front of the EVF, it's like their edges are of different thickness hence you get the smearing. It's not really a big deal for me since the EVF is just for framing. However if you're manual focusing with the EVF, keep your eye in the centre or it will be difficult to tell what is in focus.
Other than that, the refresh rate seems better.
- AUTOFOCUS -
It's almost instantaneous. With the responsive touchscreen, you can also choose the AF points quickly.
- IMAGE QUALITY -
ISO performance is about 1 stop better than GH2. Personally I will stay around ISO 3200 and below. Noise detail is quite rough at high ISOs.
Colors are fine. Because of the improved dynamic range, photos feel like they have more depth. I still prefer the colours of X-Pro1.
They lost the multi-aspect sensor so the 3:2, 16:9, 1:1 ratios are 14MP, 14MP and 12MP. Not really a big deal unless you really need higher resolutions.
For stills, the sensor seems less capable of creating moire. For example with GH2, if you're shooting a book with a picture on it, more than half the time you'll get moire. In real life, moire problem is rare. I'm saying this because sometimes I have problems with the GH2 but not anymore with GH3.
- VIDEO -
Strangely, there's higher tendency for moire to appear than GH2. Moire is slight. However, it's irritating if you can't use a footage because of moire. It's not easy to spot video moire on LCD and that adds to the problem. For production work, you will need on set to have a screen capable of displaying 1080P. I'm a bit disappointed in this area. There are several discussions online about this issue and I will suggest you read up more if video is important to you.
For the 1080P 50FPS or 60FPS, you get up to 50Mbps output. Lower FPS gives you 72Mbps. That's some detailed video files to work on. At 1080P 50FPS, it's about 10MB per second of footage. Get a huge SD card. I recommend the Transcend Class 10 UHS 85/45 MB/s because it's value for money.
- PERFORMANCE -
I can get about 500 shots with some video. Battery is amazing.
You can now utilize the full speed of a 95MB/s SD card with the GH3, an improvement over GH2.
Menus are quick and simple to navigate. Overall functionality feels responsive.
- OTHER STUFF -
Electronic shutter is nice. You can shoot silently in RAW up to ISO 1600. It's great to use it with the inbuilt intervalometer for timelapse so you don't have to use the physical shutter.
There's Wifi and I believe you can download some iPhone app to work with the camera. I don't use this so I can't comment further.
I love the many customizable function buttons. There's a list of menu items you can assign to them. The bad thing is, for some buttons, that list can be much shorter so you won't get to set what you want to that one particular button even though you can do so with the other button. Why do this, Panasonic?
- CONCLUSION -
Should you upgrade from GH2? I did, and I did it for the ergonomics, video, and better dynamic range. If you want to upgrade for video, I suggest you read up more on the video moire issue. If you're just upgrading for the better image quality, well, you'll have to judge the price over value ratio yourself. For dynamic range, I can understand. For ISO performance, why not try a faster lens if possible?
Why do I have the X-Pro1? I love Fujifilm's colour, and the manual way of shooting (aperture rings on lens). For leisure, I use the X-Pro1. It is a video moire monster which is why I still need Micro Four Thirds.
GH3 is a workhorse to me. If I'm on assignment and unfamiliar with the ground, I will bring the GH3 -- no thinking required. It is feature packed, capable and predictable. With the whole family of Micro Four Thirds lens, it covers all sorts of shooting situations. I was on board a ship recently and had to use the widest lens possible for tight spaces, the Panasonic 7-14mm lens. I stood 4 hours with the camera and lens (850g) hanging over my neck. There's some strain at the end of the day, but I won't trade this setup for anything else.
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