GH5 GH5 120 fps in 10bit?

R

Ryanite

Member
Do you think it's a possibility for he GH5 to get an update for 120 10bit HFR? It's something that looks to be a powerful feature of the pocket 4k, to not have to compromise the grade to 8 bit footage sounds amazing.
 
I doubt it. I believe its a processing power issue more than anything else. Just not enough CPU cycles in the camera to make that happen I fear.

To be honest it isn't just the lack of 10bit that hurts the slow motion on the GH5 compared to the p4k. The method the sensor is scaled down is also inferior compared to the p4k. The p4k does however crop the sensor to shoot 120p so its also not as easy to shoot with for wider angles.
 
GH5 is doing quite the bit of processing under the hood, NR, lens profiles, computing for IBIS so I can see how it's taking a heavier load than the P4K but the skeptic in me has me feeling like it may be capable of even 4k 60 10bit and 120 10bit but a certain cinema line is being protected, much like this strange V-log L that's so necessary for some reason.
 
Very excited for the 120 from the P4K, it will be incredible.

On the GH5, shoot 120 to non-VLog (i.e. Cine-D), and *brightly expose. The sensor readout is limited, but better at 120 than 180, and the bitrate starved in the shadows.
As a true motion nut, the I frame codec + pure sensor readout for 120 on the P4K is going to be stunning
 
Anybody know if the p4k can always be shot in crop mode? Would be nice to always shoot that way to match 24p and 120p shots.
 
Sage said:
Very excited for the 120 from the P4K, it will be incredible.

On the GH5, shoot 120 to non-VLog (i.e. Cine-D), and *brightly expose. The sensor readout is limited, but better at 120 than 180, and the bitrate starved in the shadows.
As a true motion nut, the I frame codec + pure sensor readout for 120 on the P4K is going to be stunning
Click to expand...

Not to mention recording HD to raw (4:4:4) will up convert to 4k a lot cleaner. 4:2:0 and 4:2:2 highly compressed up scaled to 4k blows up those nasty artifacts and makes them so much more visible and apparent.
 
Thomas Smet said:
Anybody know if the p4k can always be shot in crop mode? Would be nice to always shoot that way to match 24p and 120p shots.
Click to expand...

In raw a crop at the same size as when at 120fps which is around 4x crop isn't enough pixels to output 4k. You can shoot 1080p cropped when using raw though. Prores 1080 will downsample I believe.

Theoretically you can use the old bmpcc speedbooster aand get an extra stop of light and a 2.3x crop but I'm not sure Ive seen it tested yet.
 
At least according to these specs, the Sony IMX294 sensor (which is reportedly used in both the GH5s and Pocket 4K) is capable of a full sensor readout at 120 fps with 10-bit output:
https://www.sony-semicon.co.jp/products_en/new_pro/may_2017/imx294cjk_e.html

Since the Pocket 4K only supports HD windowed at 120 fps and the GH5s only 8-bit, that suggests both cameras have processing limitations when handling a full 4K readout at 120fps. In the case of the Pocket 4K, it's possible that part of the motivation for windowed 120fps was to enable 12-bit readout from the sensor rather than 10-bit. In the case of the GH5s, the sensor readout limitations might explain why the 120fps HD modes look better than the higher frame rates like 180fps (since anything above 120fps can no longer do a full sensor readout).

Still, it would be nice if Panasonic or Blackmagic were able to unleash the full potential of the sensor.
 
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