GH5 & compressed 10 bits - Any gain ?

[OliKMIA]

I got a GH5 and I love it. However I always had doubts about the 10bits thing. What's the point of 4K in 10 bits with such a low bitrate ?

Of course I'm aware of the incoming 400mbps upgrade but this bitrate will use a less efficient compression mode. In other word the bitrate will be higher but the compression will be less efficient, so back to square one (even though it will surely help for editing, All-I being less intensive for the computer)

- Right now the 150mbps 10bits mode uses the IPB (interframe) compression method

- The new 400mbps 10bits will use the All-I (intraframe) compression method

After doing a few grading tests I was not able to see any clear difference between the 8 bits and 10 bits modes unless I pushed the slider to unreasonable ends, in any case, both image were unusable at this point.

Just to be clear, I really like the GH5, no regrets here. I'm also not a pro colorist. So what do you guys think based on your experience so far ? Have you seen clear advantages with the 10 bits mode ?

[tweak]

If you look to MLraw threads you will see a similar opinion to yours. People were so excited about the new option of recording in 10bit Raw, but in reality they soon discovered that 10bit Raw isn't really as useful as they would have thought. 12bit Raw is kind of the minimum to be bothered shooting with and 14bit Raw really highlights the positives of shooting a file in Raw format. Obviously the GH5 isn't shooting Raw, but I would think a similar theory would apply (afterall 10bit is 10bit). You may get a slight bit of an advantage in colour grading but ultimately a well exposed 8bit h.246 file vs a well exposed 10bit h.246 file is going to be indistinguishable to the end viewer... I wish these companies would give us a proper Raw option. GH5 with 14bit Raw would be an amazing camera.

[OliKMIA]

I think the point is not much about 10/12/14 bits but about the amount of data behind (the bitrate). Some camera record in 10bits prores HQ with massive bitrate and the difference is very visible over 8 bits.
It's like having a car with an amazing engine (10bits) but the transmission (bitrate) is not designed to handle it so in the end there is no real difference.
Anyway, I'm just checking if I'm missing something. So far I'm very happy with the GH5 and I mostly shoot in 4k60, I find the colors to be better than the GH4 and the codec is doing good.

[hyalinejim]

You'll really see the advantage of 10bit in VLog. 8bit will apart straight away whereas 10bit is fine.

[tweak]

47 minutes ago, OliKMIA said:

I think the point is not much about 10/12/14 bits but about the amount of data behind (the bitrate). Some camera record in 10bits prores HQ with massive bitrate and the difference is very visible over 8 bits.
It's like having a car with an amazing engine (10bits) but the transmission (bitrate) is not designed to handle it so in the end there is no real difference.
Anyway, I'm just checking if I'm missing something. So far I'm very happy with the GH5 and I mostly shoot in 4k60, I find the colors to be better than the GH4 and the codec is doing good.

Is why I brought up MLRaw, which has a much higher bitrate yet still the advantages in 10bit aren't that great.
Above poster is right, V-log makes more of a difference, but there's still some drawbacks in certain situations.

[PannySVHS]

 

Hey guys, it seems your findings are not optimistic enough when it comes to the benefits of 10 bit in the GH5 for only 20% more data you get 3 to 4 times amount of shades.

This example has been shown before and is showing the obvious benefits of 10bit in the GH5 versus its 8bit.

 

[Orangenz]

Best bang for the buck. If you want better, go RED at $50-100K+ and by better I'm really talking more about the extra 2 stops and ease of editing access. I don't know what "slider" you're talking about but the difference in grading of more plain backgrounds like sky is HUGE and totally gets me the image that I always wanted the GH4 to give with vlog. The codec and compression goes with the price point but the whole "this is too small for any decent image" is kinda bollocks as it has a good history across all the GH cameras. The kind of conversation goes like this: me- yes!! no magenta blobs in that cloud!! family member- i see no difference, they both look great.

[OliKMIA]

3 hours ago, Orangenz said:

Best bang for the buck. If you want better, go RED at $50-100K+ and by better I'm really talking more about the extra 2 stops and ease of editing access. I don't know what "slider" you're talking about but the difference in grading of more plain backgrounds like sky is HUGE and totally gets me the image that I always wanted the GH4 to give with vlog. The codec and compression goes with the price point but the whole "this is too small for any decent image" is kinda bollocks as it has a good history across all the GH cameras. The kind of conversation goes like this: me- yes!! no magenta blobs in that cloud!! family member- i see no difference, they both look great.

Thanks for your feedback. I'm not bitching at the GH5, I have one and I love it. I'm also not trying to make silly comparison with a RED.

All I'm saying is that so far I haven't really seen the advantage of the 10 bits codec and I have doubts about any real gains considering the amount of compression. People are also getting very exited about the new super expensive V60 card to get the 400mbps bitrate but it will be All-I  and I'm not sure there will be any image quality gain neither. Personally I will stick to the current codec.

That being said I'm not exactly a pro-colorist or codec expert I'm interested about your opinions here based on real life shooting experience.

[jcs]

4 hours ago, PannySVHS said:

 

Hey guys, it seems your findings are not optimistic enough when it comes to the benefits of 10 bit in the GH5 for only 20% more data you get 3 to 4 times amount of shades.

This example has been shown before and is showing the obvious benefits of 10bit in the GH5 versus its 8bit.

 

This JPG image is 8-bit 420 (everything we see online and with normal monitors is 8-bit. To see 10-bit one needs a 10-bit display, a video card capable of 10-bit output such as a Quadro/FirePro, and OS+software capable of 10-bit output (e.g. Photoshop)). The banding was caused by post grading where the 8-bit capture (Vlog?) wasn't sufficient for the grading, whereas the 10-bit version's extra bits allowed the final edit to be compressed to 8-bit 420 without banding. If one can't see the advantages of 10-bit and needs to save disk space, shooting 8-bit is a good idea.

[Axel]

7 hours ago, OliKMIA said:

Of course I'm aware of the incoming 400mbps upgrade but this bitrate will use a less efficient compression mode. In other word the bitrate will be higher but the compression will be less efficient, so back to square one (even though it will surely help for editing, All-I being less intensive for the computer)

All-I will be almost indistinguishable from long-gop. It will not spontaneously be perceived as "better". As with many things regarding improvements in video quality it's actually the other way around. On the long run, with hundreds of clips to compare between, you will finally consider the lower bitrate as "worse". You will start to notice evidence of temporal compression artifacts, usually negligible. The higher bitrates of the GH2 hacks didn't show more detail, as was often stated. When there was a weak signal in dark image areas, the highly efficient 24Mbit factory codec compressed noise out of the video. The 50-70-170 (or so) hack-bitrates dithered the shadows with random noise. This looked more natural. Many want a less efficient compression for the slightest chance that the image looks better.

[OliKMIA]

1 hour ago, Axel said:

All-I will be almost indistinguishable from long-gop. It will not spontaneously be perceived as "better".  Many want a less efficient compression for the slightest chance that the image looks better.

Yeah, exactly, I have the felling that this 10 bits thing just a new marketing thing (maybe I'm wrong, some people here notice a difference in V-Log).

A little bit like the mega pixel or zoom race until people realized that having a lot of Mpx with a shitty lens was useless. On the GH5 I'm not sure about the gain of 10bits with "shitty" bitrate. I mean, I was editing 10 bits ProRes from the Inspire 2 recently and the difference is very clear during grading (as well as the huge size of the files).

So far I haven't found any serious review about the 10 bits mode except a ton of "youtube experts" with questionable background. Hopefully @Andrew Reid will check this aspect soon on his GH5. 

 

[Vesku]

GH5 has 6k video. It has many times more 10bit information than GH5 normal 4k 10bit video. The 200Mbs ipb h.265 codec has enough bitrate and data. It lacks 24P but maybe FW update will fix it.

[Axel]

1 hour ago, OliKMIA said:

Yeah, exactly, I have the felling that this 10 bits thing just a new marketing thing (maybe I'm wrong, some people here notice a difference in V-Log).

See this video (from 1'15").

You won't notice it at first glance, but the more clips you compare, the more your eyes will be able to identify the differences. I think if the camera can do 10-bit, it should be a no-brainer to use that. I decided for the A6500, but in order to have no banding, color artifacts and the like and still a very good DR, I have to forgo extreme grading and slog 3 and expose very well.

I've read somewhere that Like_rec_709, as is, had the same DR as V-Log (which wasn't written for the GH5 but for Varicam anyway, therfore "V") after the normalisation Lut. Free, easier to handle. Would use it in 10-bit too if it were my camera ...

[OliKMIA]

Thanks for the info Axel. So far I'm having very good results with the 709 Like and Natural profile in 8 bits mode.

Good point about the Varicam, actually I found this official Panasonic document about VLOG production. Interesting read

http://pro-av.panasonic.net/en/dvx4k/pdf/ag-dvx200_tech_brief_vol6_en.pdf

[hyalinejim]

3 hours ago, Axel said:

I've read somewhere that Like_rec_709, as is, had the same DR as V-Log

Not according to Paul Leeming's tests: VLog has one stop more than Cine D, which in turn has ever so slightly more DR than Like709, even with knee adjusted.

[jonpais]

2 hours ago, hyalinejim said:

Not according to Paul Leeming's tests: VLog has one stop more than Cine D, which in turn has ever so slightly more DR than Like709, even with knee adjusted.

I thought Paul Leeming said V-Log on the GH5 had two stops greater dynamic range than Cinelike D, but the last I checked was a few weeks ago.

[Axel]

Found the source, an editorial article on the GH5 on the german slashCAM forum. Excuse the weird language, it's just the Google translator:

Quote

 

First we have the GH5 generated V-Log L values for the first time in a editing program. After Premiere Pro and Resolve under Windows still here still patzen or the files can not even read correctly, EDIUS showed in the version 8.32 as it should be. 

The program reads the 10 bits  4: 2: 2  Files of the GH5 with the firmware 1.0 exactly as it was already defined at GH4 times for the introduction of V-Log L. Thanks to 10 bits  Color-Picker in Edius you can clearly see the white level at 720 and the black level at about 175 (+/- the occurring noise). 

Where these points should lie exactly can be seen so far only from a graphic from Panasonic to V-Log L, which we copied with the normal V-Log curve. There you can also see, among other things, that V-Log L and V-Log apart from the "light-bend" also in other places somewhat diverge: 
 

According to this graph, the values for V-Log L in Edius are really where they should be. But so far there is only one Panasonic recommended LUT for equalization, namely the "normal" V-Log LUT for the Varicam with a Super35mm sensor, which transmits the signal into the REC709 color space. After using this LUT in EDIUS, the black value is about 64 and the white value is 1020. So if everything is green, the LUT mapples the entire signal as desired almost completely over the entire project color space (in Rec709). 

Nevertheless, we see a fundamental problem at this point: because the compatibility of the larger Varicam S35 sensors with more dynamics, the recording of the entire sensor level on the GH5 fills the possible 10 bits Not full. The camera uses only the values from 175 to 720 in the 10-bit recording as described. This would correspond to 545 possible values, which are also almost 9 bits  (Which would correspond to 512 values). 

9 bits  Are already significantly more than 8 bits  , But with V-Log L you choose a compromise, which is due to compatibility with Varicam. V-Log L material should be easily with V-Log on the Timeline  And for this "compatibility to the big sister" the GH5 sacrifices almost half the possible color resolution. If, on the other hand, you are using alternative (and free) profiles like Cinelike D, you can really fill the entire recording bandwidth from 0 to 1023. If there was a standardized LUT, this would be the better choice on the GH5 vs. V-Log. 

But there are already better alternatives. For Panasonic, the GH5 has given another profile, which is called "Like709". And with this profile, a knee function can be used for the first time in the camera. So you have to deal with a normal 709 profile, where you can manually determine from which point the lights should be compressed. This profile can be similar to Rec709, ie you can work quite regularly in the Rec 709 color space and has "only" the lights compressed. But since in 10 bits  As a rule, sufficient values are still available for the compressed sensor data in the lights. And this should be for many users actually more interesting than V-Log L.

 

 

[Fritz Pierre]

11 hours ago, OliKMIA said:

Thanks for your feedback. I'm not bitching at the GH5, I have one and I love it. I'm also not trying to make silly comparison with a RED.

All I'm saying is that so far I haven't really seen the advantage of the 10 bits codec and I have doubts about any real gains considering the amount of compression. People are also getting very exited about the new super expensive V60 card to get the 400mbps bitrate but it will be All-I  and I'm not sure there will be any image quality gain neither. Personally I will stick to the current codec.

That being said I'm not exactly a pro-colorist or codec expert I'm interested about your opinions here based on real life shooting experience.

The big difference you will notice in the sky or a white wall behind a subject....and in 10 bit what you notice is the absence of problems....and of course a huge difference in grading....it's only on a rare occasion that the camera goes near 150Mbps anyway...say when you're shooting a scene with a fast flowing water and ripples...150Mbps is a gigantic amount of information getting written in a second...the discussions about this (not referring to you here) have just defaulted here to is this "150Mbps container" large enough...and the answer is yes...the 400 upgrade is all Intra and though it may handle certain kinds of motion better, so it will have its place in the GH5's toolset, it will not give you a better image than 150ipb under 98 percent of circumstance...when optimal image quality is truly the order of the day, shoot Prores at 800mbps instead on an external recorder....the truth is you'll never really go near that aquisition rate, as probably under those circumstances you will also be lighting a scene with proper production design, wardrobe etc. and on and on...the point is you already have an incredible camera in your hand for its size....or any size for that matter, and for an additional $1000 you can record in Prores to SSD's at 800mbps if the container size is truly a concern.

8 hours ago, OliKMIA said:

Yeah, exactly, I have the felling that this 10 bits thing just a new marketing thing (maybe I'm wrong, some people here notice a difference in V-Log).

10 bit is huge....no marketing scam!!!

43 minutes ago, jonpais said:

I thought Paul Leeming said V-Log on the GH5 had two stops greater dynamic range than Cinelike D, but the last I checked was a few weeks ago.

Leeming said at least  2 stops...maybe even an additional 1/4 or 1/2

23 minutes ago, Axel said:

Found the source, an editorial article on the GH5 on the german slashCAM forum. Excuse the weird language, it's just the Google translator:

 

Leeming's LUT takes care of this beautifully...even allows you to match Cinelike D and Vlog as at high ISO Vlog seems to get noisy.

[deezid]

Paul Leeming is right on this topic. I dare to say the GH5 has a better dynamic range than the GH4 in V-log since the shadows are way cleaner thanks to the new sensor and downsampling.

To see the benefit I don't need my 10 bit LG 4k screen, after grading the 8 bit footage looks horrible while the 10 bit footage still doesn't show any banding.

[OliKMIA]

Thanks guys for all your very interesting feedback.

So according to this guy there is no advantages of using 10 bits because of the low bitrate

 

 

On the other side plenty of people are also reporting real gain using 10 bits.