GH5 Where's everyone at with V-Log vs a Rec709 Profile?

Yeah its pretty simple. Expose for skin if you are shooting people. If its nature or landscape you can get away with just setting the zebras to clipping point and exposing a bit under that. Of course that doesn't always work either as in some cases that will get you an almost silhouette type of shot.


I think its worth while to see how much you can underexpose skin before it goes to crap. On my XT3 I've found I can easily recovery them with zebras at 55 for Caucasian skin.
 
The GH5 has a pretty limited DR and significant noise in the lower areas of the tonal range. For this reason it's very easy to blow highlights and get a 'digital / video' looking image or struggle with noise. For this reason ETTR when used in an informed way is a good exposure practice for this camera and I dispute the claims that it is 'terrible' - this is just hysterical language . When I say informed way I'm not talking about slavishly preserving the highlights in every shot but pushing the exposure as far as it will go to the right while maintaining a sensible tonal balance. Whatever exposure method you use you have to be aware of the limitations of the sensor. I understand the concerns for colorists in matching shots but there has to be a tradeoff if you are using a budget camera with it's limited sensor capabilities. V-LOG L is poorly implemented on the GH5 as it restricts the tones to a limited data range which even with 10bit 4.2.2 can be an issue in post and HLG offers an alternative where more of the data range is used. I'd rather see a properly implemented V-LOG for capture for sure but like everything on a budget camera HLG is a good compromise if you understand it.
 
Shirozina said:
The GH5 has a pretty limited DR and significant noise in the lower areas of the tonal range. For this reason it's very easy to blow highlights and get a 'digital / video' looking image or struggle with noise. For this reason ETTR when used in an informed way is a good exposure practice for this camera and I dispute the claims that it is 'terrible' - this is just hysterical language . When I say informed way I'm not talking about slavishly preserving the highlights in every shot but pushing the exposure as far as it will go to the right while maintaining a sensible tonal balance. Whatever exposure method you use you have to be aware of the limitations of the sensor. I understand the concerns for colorists in matching shots but there has to be a tradeoff if you are using a budget camera with it's limited sensor capabilities. V-LOG L is poorly implemented on the GH5 as it restricts the tones to a limited data range which even with 10bit 4.2.2 can be an issue in post and HLG offers an alternative where more of the data range is used. I'd rather see a properly implemented V-LOG for capture for sure but like everything on a budget camera HLG is a good compromise if you understand it.
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It's isn't hysterical language, it just goes to why I didn't give an explanation in the first place. I'm glad all these problems were solved for you by ETTR.
 
I've just shot some tests. I decided to focus mainly on V-Log L, as I'm most familiar with log shooting. I did also chuck a quick HLG test in:

Custom white-balanced with Kenco Vari-ND.

V-Log L material - using no LUT, the Panasonic V35v100 LUT and the Leeming Pro LUT V-Log. I also chucked in the Sony SLog 3 SGamut3Cine LUT, just out of curiosity.

HLG - using no LUT and the Leeming Pro LUT HLG to 709.

I didn't like HLG at all, for what it's worth - could be the vari-ND. Dunno - but that's what I currently plan to use when I need ND.

My results:

The best exposure in this V-Log L scenario was skin tone set to 50IRE.

In terms of expectation bias, I'd almost convinced myself the Leeming LUT was a wrongun.

However, it ended up being a toss-up between the Leeming Pro LUT V-Log and the Sony SLog 3 SGamut3Cine LUT. The Panasonic LUT was not so kind with mid reds in the skin tones.

The Leeming Pro LUT V-Log won me over this time. I'm pleasantly surprised.

Ben.

Leeming V-Log L.jpg
 
The Panasonic LUT is for V-LOG. The GH5 doesn't have a V-LOG picture profile - it's V-LOG 'L' ( Low, Light, limited??) hence the issues.
 
Shirozina said:
The Panasonic LUT is for V-LOG. The GH5 doesn't have a V-LOG picture profile - it's V-LOG 'L' ( Low, Light, limited??) hence the issues.
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However, it’s the LUT that Panasonic themselves distribute and specify for the GH5/S. I agree it’s confusing and undermines confidence. The test results yesterday suggest to me they either just cocked it up - or didn’t have the know how/resources in the Lumix division to roll their own.
 
In my experience, HLG and V-Log-L are only useful if shooting to an external recorder and bypassing the internal h.264 compression.
When recording internally, even in 10-bit (which is the only way you can record HLG), ugly magenta/cyan blotches appear in mid to dark gray areas of the image. An encoding error, as I understand it. So what would be buried/invisible in the dark shadows in a REC 709 profile gets lifted and rears it's ugly head when using LUTs to convert V-Log or HLG to REC709.

I've shot the same image using HLG, V-Log, Natural and Standard profiles. The V-Log and HLG might squeak a little more highlight detail and/or shadow detail into the image, but the dark midtones always have a dancing, noisy magenta/cyan thing going on that can't be ignored.
Plus, there seems to be no end of speculation as to how to get good skin tones by using different LUTs, etc.

But the fact is, Natural and Standard do a pretty damn good job right out of the box. I realize this is subjective, but after all my fussing, it occurred to me that footage I shoot using the REC709 profiles not only looks just fine, but is easier to expose while recording in the field, and looks better at the end of the day.
 
Tom Roper said:
I disagree with most of that, brother.
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I'd be interested to know which parts you disagree with. If it's the verifiable (to my eyes) magenta/cyan noise in the shadows, I'd be very interested in finding a solution to that.
To me, that's the stumbling block that keeps me from pursuing it any further. Any other advantages to GH5 implementations of log shooting are nullified by that.
 
I’ve been shooting the GH5 in VlogL without any issues for two years.


dvbrother said:
I'd be interested to know which parts you disagree with. If it's the verifiable (to my eyes) magenta/cyan noise in the shadows, I'd be very interested in finding a solution to that.
To me, that's the stumbling block that keeps me from pursuing it any further. Any other advantages to GH5 implementations of log shooting are nullified by that.
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icarusfilm said:
I’ve been shooting the GH5 in VlogL without any issues for two years.
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What LUT do you use?
I ask because the LUT must be the variable that's causing my results. I know how to expose the GH5 properly for V-Log. I know how to light. And I have performed over/underexposure tests with V-Log, HLG and Standard and Natural profiles.

So it must be the LUT I'm using. I do not use Resolve. I use Lumetri in Premiere.
 
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dvbrother said:
I'd be interested to know which parts you disagree with.
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I agree that standard and natural are good profiles. All the GH5/Gh5s shooters I work with, wedding, corporate, events are using VLog-L. I also shoot HLG, which is more exposure critical but I like it more personally. i use Resolve but others use PP successfully.
 
So, Ben, I know it's not helpful to the discussion - and sorry for the digression off topic - but I have to ask....
Do you miss your 18 - 110 and FS7 yet?
 
markfpv said:
So, Ben, I know it's not helpful to the discussion - and sorry for the digression off topic - but I have to ask....
Do you miss your 18 - 110 and FS7 yet?
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Good to hear from you, Mark!

:) Looks like I started a fire, right?

Ask me at the end of August, when we finish a 3 week shoot!

I don’t miss the size/weight of the FS7 and 18-110 plus vlocks and Gratical EVF etc, and I’m really enjoying the challenge of getting to know a new system. The thing I probably miss most right now is the simplicity of Cine EI and a simple WB preset.

But for the discrete doco project we’re embarking on next month, 10 bit video in such a tiny package puts a huge smile on my face.

I had hoped the A7S3 would have been out and established by this time, but it was not to be, and I was getting such surprisingly good results from the GH5S as a B cam to the FS7 this past few months, that’s what finally tipped me into going fully MFT for video shooting. I’ve still got a comprehensive set of nice Sony E glass for stills, so that door’s always open...
 
dvbrother said:
What LUT do you use?
I ask because the LUT must be the variable that's causing my results. I know how to expose the GH5 properly for V-Log. I know how to light. And I have performed over/underexposure tests with V-Log, HLG and Standard and Natural profiles.

So it must be the LUT I'm using. I do not use Resolve. I use Lumetri in Premiere.
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What LUT are you using ? Never seen the problems you describe unless I have underexposed footage. Again the GH5 has not got a lot of DR and the lower part of the tonal range is quite noisy so you need to be 'generous' with exposure to avoid this even if it's not strictly the 'correct' way to expose LOG. I personally use Resolve and either a Colour Managed workflow or a color space transform node to convert to Rec709 as I find LUT's need 'correct' exposure to work effectively. Skintones in particular can easily go very magenta if the REC709 conversion is not done properly.
 
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