GH4 Exposing V-LOG L

The V-LOG to 709 LUT in the dLOG package doesn't perform satisfactorily. Not only does it not address the magenta issue, but its color and exposure are way off:

dLOG709
emma_dlog_1080.jpg

VLOG709
emma_vlog709_1080.jpg
 
I've spent the last couple of days iterating on the LUT to make it perfect. Here's how v0.81 looks on the same clips as previously posted :D

LeemingLUT_One_BETA81_ISO400.jpg


LeemingLUT_One_BETA81_ISO6400.jpg


I'm in the process of writing the manual now and giving it to a beta tester to bash, before I prepare it for sale.

Price will be US$15 - Not only cheaper than most other LUTs out there, but markedly superior IMHO! The dynamic range I'm getting is incredible, and colour noise is so well controlled it's crazy, even at ISO 6400 :D

I'm confident in saying that I prefer this over V-Log for colour rendition, not to mention cleaner colour and a simpler shooting workflow! I can only imagine what I can get from this LUT with external, 10 bit recording!

As usual, grab the full, 4K PNG files here to see it without any compression:

http://www.visceralpsyche.com/misc/web_images/LeemingLUT_One_BETA81_ISO400.png

http://www.visceralpsyche.com/misc/web_images/LeemingLUT_One_BETA81_ISO6400.png

Remember, this is 8 bit 4:2:0 internal recording to MP4 100Mbits....

Cheers from Berlin,

Paul :)

P.S. This clip had a negative highlight curve applied which is why you are seeing some slight solarisation on the arm highlights. With neutral settings for highlight/shadow there is no solarisation.
 
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Dan Keeble said:
I thought this thread was about exposing V-Log footage :undecided
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I admit the thread's title doesn't really reflect the main thread any more :D

Start here and you'll understand more: http://www.dvxuser.com/V6/showthrea...-LOG-L&p=1986578246&viewfull=1#post1986578246

That said, exposing V-Log is a nightmare as none of the tools function as they should to give you consistent, reliable exposure.

More importantly, the image problems with YUV chroma smearing internally etc mean that we've kind of turned this thread into a 'best image quality from the GH4' discussion, more than the title implies at this point.

Cheers,

Paul :)
 
That are things that could not be confirmed in either Resolve nor in Vegas. And I do not see why the exposure setting should not be possible. Set the GH4 internal zebra to 80% and you have a point to avoid clipping at IRE79 of v-log l. Set it even to a lower figure to get better skin tones. The GH4 internal histogram is rescaled if one switches to v-log l. So it is simply wrong to state that there are no GH4 internal tools to adjust the luma. Sure, with the waveform monitor of the Shogun one has much better tools.

To my opinion the reasons for chrom smearing are not understood by now really. Could be that this is a Premiere issue only, since that behaviour has not be confirmed in Resolve or Vegas. Could also be that it is an issue of setting color saturation in a range of 200 to 300%. Or it could be an issue of the internal codec too. Or it could also be an preview issue maybe. Using ProRes of the Shogun and transforming the files to Cineform does not show that in a 32bit floating point project in Vegas, and also the internal playback from the Shogun does not show that either with (or without) the Pana prieview lut to rec709 applied.

So to blame v-log l for but to offer CineD luts instead? Well I have seen significant noise in such profiles in the lowlight areas of first test footage - noise that is stronger then with v-log l with approriate settings. That would be also a nogo since flat profiles are of interest in situations with high contrast maybe also in combination with lowlight.
 
wschmid said:
To my opinion the reasons for chrom smearing are not understood by now really. Could be that this is a Premiere issue only, since that behaviour has not be confirmed in Resolve or Vegas.
Click to expand...

Nope its not a Premiere only issue, its there just the same in AE in 32 bit space as well.
Its a flaw in how Panasonic implemented it, its not in the DVX200 either according to Barry Green, same 8 bit codec, same M4/3 setup, same V-Log.
Panasonic botched it...plain and simple, they should have mapped the V-Log for the GH4 12 stop range right at the beginning instead of mapping it to the Varicam minus 2 stops and roll off at 79 IRE.
They did a terrible job., thats the truth, its not even implemented as nicely as the DV200 version, as Barry Green said, whats happening in the GH4 is profoundly unacceptable, if a hacker had done this job of creating V-Log, they would be getting all kinds of
flak. Also notice that all the beta testers have been very silent since its release.

wschmid said:
So to blame v-log l for but to offer CineD luts instead? Well I have seen significant noise in such profiles in the lowlight areas of first test footage - noise that is stronger then with v-log l with approriate settings. That would be also a nogo since flat profiles are of interest in situations with high contrast maybe also in combination with lowlight.
Click to expand...

Agreed!! I personally dont like anything about Cine D and although I will probably buy Pauls LUT (the images he has posted definitely look good) I think he should stop spamming these threads and start his own thread about his Cine-D LUT.
Even tho V-Log should perhaps be re named V-Dog...this thread should be left to the original exposing V-Log title even tho its gone off subject many times, the spamming of Paul is starting to look really over the top.
Cheers
 
astromann said:
Nope its not a Premiere only issue, its there just the same in AE in 32 bit space as well.
Click to expand...

It has been confirmed that the magenta blocking issue is not present with 422 10-bit recordings in AE 32-bit color space. It is of course still present in AE 32-bit color space when the source is 8-bit internal. I will be able to confirm this personally tomorrow when my Atomos Ninja Star arrives (couldn't pull off enough money for 422 10-bit in 4K, but HD will do just fine for now).
 
The best way to expose for V-Log is a monitor that supports false color or LUTs. Shy of that, and you are going to be just ball parking it. I wish I could find some confirmation whether or not the Blackmagic Video Assist does false color, but every demo I could find only shows a histogram, which just won't cut it.
 
astromann said:
Nope its not a Premiere only issue, its there just the same in AE in 32 bit space as well.
Its a flaw in how Panasonic implemented it, its not in the DVX200 either according to Barry Green, same 8 bit codec, same M4/3 setup, same V-Log.
Panasonic botched it...plain and simple, they should have mapped the V-Log for the GH4 12 stop range right at the beginning instead of mapping it to the Varicam minus 2 stops and roll off at 79 IRE.
They did a terrible job., thats the truth, its not even implemented as nicely as the DV200 version, as Barry Green said, whats happening in the GH4 is profoundly unacceptable, if a hacker had done this job of creating V-Log, they would be getting all kinds of
flak. Also notice that all the beta testers have been very silent since its release.

...

Agreed!! I personally dont like anything about Cine D and although I will probaby buy Pauls LUT (the images he has posted definitely look good)
Click to expand...

Well, maybe we do not know enough. Maybe it is an Adobe issue, maybe not. At leat I can confirm that I do no see the issue with 10bit ProRes from the Shogun in Vegas with 32bit project settings. Other user have confirmed that they do not see it with Resolve. Also Barry seem to have no idea what is going wrong here. We simply do not know yet.

But since it works with the Shogun I wonder if we can state really that it is unacceptable. Maybe for the internal 8bit recording only?

I have some understanding why they have not developed a brand new vlog-GH4 - even if I would have liked to see that too, instead of cutting the luma at IRE79. But what I see here with my Shogun is that one can work with it - BUT for sure it makes more sense to record to 10bit or even higher, given the reduced luma range.

I am not sure if I like the idea to use CinelikeD instead v-log l. Not after the noise that I have seen here in lowlight situations. With enough light that is no issue at all.
 
astromann said:
Agreed!! I personally dont like anything about Cine D and although I will probably buy Pauls LUT (the images he has posted definitely look good) I think he should stop spamming these threads and start his own thread about his Cine-D LUT.
Even tho V-Log should perhaps be re named V-Dog...this thread should be left to the original exposing V-Log title even tho its gone off subject many times, the spamming of Paul is starting to look really over the top.
Cheers
Click to expand...
Fair enough :) I'm not trying to spam in the slightest - just figuring out how to get the best images out of the GH4 using internal recording. And so far that's turning out to be Cinelike D, which is as surprising to me as it is to everyone else.

Anyway, I'll limit discussion here to V-Log L and bugs with that only, and once my LUT for Cinelike D is ready, I'll start a dedicated thread for it :)

Cheers from Berlin,

Paul :)
 
wschmid said:
Well, maybe we do not know enough. Maybe it is an Adobe issue, maybe not. At leat I can confirm that I do no see the issue with 10bit ProRes from the Shogun in Vegas with 32bit project settings. Other user have confirmed that they do not see it with Resolve. Also Barry seem to have no idea what is going wrong here. We simply do not know yet.

But since it works with the Shogun I wonder if we can state really that it is unacceptable. Maybe for the internal 8bit recording only?

I have some understanding why they have not developed a brand new vlog-GH4 - even if I would have liked to see that too, instead of cutting the luma at IRE79. But what I see here with my Shogun is that one can work with it - BUT for sure it makes more sense to record to 10bit or even higher, given the reduced luma range.

I am not sure if I like the idea to use CinelikeD instead v-log l. Not after the noise that I have seen here in lowlight situations. With enough light that is no issue at all.
Click to expand...

It has nothing to do with Adobe. I use FCPX and Resolve. It's baked into the file, and the problem has always existed...it's just much more noticeable with the V-LOG L profile. You don't notice the error in your workflow because you have 4X the color resolution to work with compared to compressed, 8-bit recording.
 
Joe, I understood from postings here that with Resolve user do not see the color smearing? Do you state that you see it with Resolve and 8bit GH$ footage?
 
visceralpsyche said:
And so far that's turning out to be Cinelike D, which is as surprising to me as it is to everyone else.
Click to expand...

And here I am still not convinced yet - even not for 8bit internal recorded footage. I would like to be able to test these Cinelike D profiles, in differnt situations. Both for internal and externl recordng.
 
There are two issues at play, not related.

1. 8 bit 4:2:0 V-Log L footage recorded internally shows large amounts of YUV chroma smearing. This is baked into the file and is not a function of which NLE you are using.

2. Adobe Premiere CC 2015 has some sort of precision bug it seems, whereby ProRes422 footage at 10 bit 4:2:2 recorded externally (confirmed with both Shogun and PIX-E5 footage) shows on the timeline as 8 bit, meaning the YUV chroma smearing show up there too. This is limited to Adobe Premiere Pro - After Effects has a full 32 bit workspace and as such, doesn't have any errors. Davinci Resolve 12 works fine too on 10 bit ProRes footage. I've notified Adobe of the bug so hopefully we'll see a fix in the next version.

HTH

Cheers,

Paul :)
 
wschmid said:
And here I am still not convinced yet - even not for 8bit internal recorded footage. I would like to be able to test these Cinelike D profiles, in differnt situations. Both for internal and externl recordng.
Click to expand...
It's nearly ready, so you won't have to wait long :) Writing the manual now.

I'd be quite interested to see how it performs with external recording actually. Wouldn't that be something, if it turned out to be better than V-Log externally too!

I'm staking my reputation on it being right. I'm naming it LeemingLUT One for a reason. It's because I'm confident that it's the best way to get the highest dynamic range/correct colour footage for internal 8 bit recording. As a ten year cinematographer, getting it right is my professional business, so it'd be embarrassing if I got it wrong :D

Cheers from Berlin,

Paul :)
 
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