Queenstown, New Zealand: Panasonic has launched the Panasonic Lumix DC-GH5 mirrorless camera, the upgrade of its top of the line camera series from the two year old Panasonic Lumix DMC-GH4.* It has a host of upgrades, even more on the video front that in the still camera functionality.
But, hey, it’s a camera so let’s start with the still stuff.
There’s a welcome upgrade in sensor resolution, from the long-standing 16-ish megapixels up to 20 megapixels. Accompanying that is an upgraded “Venus” processing engine. Image processors tend to be skimmed over in discussing this kind of thing, but they bear a heavy responsibility in turning the raw output of the sensor into a usable image. Panasonic says the low pass filter has been removed as well. This is the process which reduces resolution slightly to avoid such unsightly effects as moiré, but may result in sharper detail. Both the sensor and the processor are considerably faster than their predecessor, allowing improved burst performance.
Importantly, Panasonic has introduced optical image stabilisation into the camera body. With the GH4 this was built into the lenses. It still is, but in some new Lumix lenses the OIS works in concert with that in the camera to improve stability further, providing up to five stops of stabilisation.
The GH4 had a thing called “4K Photo”. This used the video capabilities of the camera to record a series of frames, amounting to a very fast burst. Frames could be extracted by the camera or external software for saving, or for combining in some cases to ensure sharp focus on several different photo elements. There was also a “pre” setting which had the camera recording continuously to temporary storage so that when you finally pressed the shutter button, it would be able to save a second’s worth of frames from before the press as well as the second after it, making it less likely that you’ve missed the important moment.
This was limited to “4K” resolution, which is eight megapixels. With the GH5 this has been bumped up to “6K”, or eighteen megapixels, so very little resolution is surrendered for this capability. Bursts of up to 30 frames per second are possible in this mode, or up to 60 frames per second in 4K mode.
The camera’s magnesium alloy case is weather sealed and proof against dust and freezing, as well as splashes. It has been designed with heat dispersal in mind. There are now two SD card slots, and these are UHS-II rated for very high performance and allow you to swap over cards for seamless, ongoing shooting, even with video.
So, now, on to video.
The GH4 was one of the first, it not the very first, “still” camera to introduce 4K video recording. It does a fine job, but is limited, if that’s what you’d call it, to 24, 25 or 30 frames per second. That’s first class stuff, but the GH5 pushes that out further to 50 fps or 60 fps for super smooth High Frame Rate video (think The Hobbit). That is the kind of thing that really appeals to the pros. Even if one isn’t planning High Frame Rate final presentation of the video, 50p and 60p allow the easy production of smooth slow motion.
If you want really slow slow motion, then if you shoot in full HD you can record at 180fps, allowing 7.5:1 slowdown. You can also “undercrank”, which means use a slow recording frame rate (down to 2fps) to allow sped-up playback. As with the GH4, you can also do time lapse video.
Furthermore, at the old frame rates the video can record 10 bit colour at 4:2:2 resolution. If you’re a professional you’ll know what that means. If not, briefly, 10 bit colour means that each colour can have 1024 levels instead of 256 levels. R, G and B combined means over a billion colours, up from fewer than seventeen million. Yes, even seventeen million sounds like a lot, but there are many subtle graduations that simply can’t be captured with those ranges, especially if the colour is almost purely R, G or B.
As for 4:2:2, video is normally encoded with the colour at one quarter of the resolution of black and white (the “luminance” signal). 4:2:2 means that the resolution of the colour is bumped up to half that of the luminance. Disappointed it isn’t full resolution? Did you notice just about everything you see is quarter resolution?
Maximum frame rate for this quality is 30fps when using a (very fast) SD in the slot to record, but if a fast external recorder is used, then up to the full 60fps is available.