The GH4 in extended use
Our six months or so with the Panasonic GH4 have been an interesting journey. There is simply no other camera, of this type, on the market.
Some film makers have opted instead for the Sony A7S, with its full-frame sensor and great dynamic range, and low light capabilities. But the Sony only records 4K externally, not on to internal memory cards.
Others have opted for the Blackmagic Design Cinema cameras, which come in both 2.5k and 4K versions, but these are more specialist tools, focused on recording RAW and log footage. They are not the all-rounders that the GH4 has the potential to be. The Blackmagic cameras, of course, do not take stills.
With its Micro Four Thirds sensor, the GH4 should perhaps not be compared to full-frame cameras such as Nikon’s D810 or especially, the Canon 5D mk III. The Micro Four Thirds sensor is 1.33 inches, or just over a quarter of the surface area size of a full-frame chip. Super35mm (or APS-C on stills cameras) sits in between.
Using a smaller chip does mean giving up some of the advantages of full-frame sensors, including full-frame’s potential for shallow depth of field. But there is more to it than this.
A full-frame camera will have better low-light performance, as it is spreading its pixels across a larger chip. It will typically have a wider dynamic range, allowing more accurate capture of highlights and shadows. And it is easier to select a true wide-angle lens for a full-frame camera than a Micro Four Thirds model.
In practice, noise on the GH4 starts to increase visibly at settings above 800 ISO; at ISO 1600 noise is quite noticeable, and certainly more noticeable than on a 5D, although noise can be cleaned up in post. It certainly cannot compare with the low-light performance of the latest full-frame cameras such as the Nikon D750 – which produces a remarkably clean image even up to ISO 12,800.
When it comes to dynamic range, the GH4 has around 10.9 stops. This means sits somewhere between a professional video camera, such as a JVC GY-HM650, capable of around nine stops of dynamic range and a full-frame DSLR, which can run up to 13 stops (the Nikon D800). Specialist cameras, such as the ARRI Amira, continue to top the dynamic range charts, with almost 15 stops of latitude.
Having said that, the narrower dynamic range is not always a problem: it just puts more onus on the operator to achieve correct exposure, and if necessary use lighting and lenses to ensure they make the most of the GH4’s sensor. Certainly, anyone familiar with shooting on a 1/3-inch broadcast camcorder will be pleasantly surprised by the results from the GH4.
Next: Depth of field and looks