GH4 Pros / Cons 16-255 mode

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wwjd

Well-known member
Well, since SEARCH is a lump of crap... what are the pros and cons of shooting 16-255, rather than 0-255 or 16-235?

I can see 16-255 work with more cheap monitors, lifts darks out of the noisey black hole at the bottom, but keep MORE room up top as opposed to 235 mode. Am I right? My NLE can edit anything so that is not a factor.
 
I believe the GH4 in 4K natively encodes sensor information to 16-235. Setting the flag to either 0-255 or 16-255 simply expands the limited information above and below. I can not detect even the slightest increase in information when the GH4 is set to 0-255. Maybe someone else has some testing to the contrary, which I'd like to see, but from my testing setting 0-255 or 16-255 is nothing but a levels adjustment from 16-235 information.

Cheers,
Pete
 
Don't use 16-255 it is an odd format that really has no place in video. 16-235 is the video standard but it doesn't have the full 256 value range. 0-255 does but some video gear will clip 0-255 down to 16-235 so you have to be careful when using 0-255 and make sure everything you have can support 0-255.

For example a lot of external recorders default to 16-235 so when the GH4 feeds a 0-255 signal to those recorders it crushes the ends to bring it down to 16-235. This is why external recorders typically look darker or more contrasty. It has nothing to do with the recorder or ProRes but the luma range getting crushed. V-log forces 0-255 which ends up recording externally more crushed than it should.
 
All cameras detect the levels of 16 to 255 (super white), it is the TV standard (16-235) that allows shooting at a small overlap (16-255), which improves the capture of great contrasts. But the levels of super white when processing must be adapted for TV broadcasting, it is necessary to meet the standard output from 16 to 235 (white). The camera supports both modes, in the case where the output was directly transmitted without modifications you need to use levels 16-235, 16-255 in other cases.
0-255 levels are "full range", but in the vast majority is shooting in the TV norm, and the output from post is converted from the TV standard into a full range levels (for PC monitors or cinema).
Sorry for my english.
 
There is no difference in how the image gets recorded internally with these settings. It just changes the metadata for your NLE, telling it what range to interpret it with. Only reason I change it is for monitoring live, as 16-235 makes it easier to see shadow details on my external monitor. Also, as mentioned, when using an external recorder, it will change the range that gets recorded.
 
Great info here. Thanks guys!
I do grasp the "TV 16-235" deal, but I am wanting maximum capture into the camera, not worrying about TV limits.

So, does the camera REALLY only capture 16-235 in any mode, yet alter the metadata... even in the camera to show more range? IE tween 235 and 255, I am getting brighter white range, while the low end stays put on the GH4 built in historgram.... I can bring everything back to within spec on my NLE without CUTTING OFF the high or low end. What I am seeing visually, and via histogram, is more of the high end. Which is why I wanted to discuss it here.

I know that is not correct for TV, but I am thinking of the future HDR TVs and monitors with more levels to them.
Sure GH4 isnt the 16+ DR camera of choice for HDR TV, but we can still milk it and expand it.
 
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