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#1 dreifish

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Posted 13 May 2018 - 05:01 PM

Is anyone producing HDR underwater content?

 

What sort of shots/scenarios do you think would actually benefit from HDR? Usually, we don't have a lot of specular highlights or deep shadows underwater, at least not when shooting balanced light scenes where you blend the ambient light with illumination you bring down.

 

Maybe the reflections off silvery fish?

 

But I'm curious if there is potential from the technology underwater, and if anyone is doing cool things with it.



#2 Interceptor121

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Posted 15 May 2018 - 09:13 AM

Is anyone producing HDR underwater content?
 
What sort of shots/scenarios do you think would actually benefit from HDR? Usually, we don't have a lot of specular highlights or deep shadows underwater, at least not when shooting balanced light scenes where you blend the ambient light with illumination you bring down.
 
Maybe the reflections off silvery fish?
 
But I'm curious if there is potential from the technology underwater, and if anyone is doing cool things with it.

I triggered the HDR question because I consume UHD HDR content
For me HDR BT.2020 has two benefits
1. Wider gamut and colour depth compared to REC709 10 bit
2. Higher value of maximum illumination

1. Comes useful even in portrait work but is not specific to HDR though is required for HDR
2. Backlight scenes, caves shot in natural light with black and bright openings, seascapes, sunburst shots

All the scenes in 2 you usually try to avoid or expose to avoid burning highlights with HDR you should be able to shoot and reproduce as is

Well this is what am hoping for based on the scenes that I see give the largest benefit on land


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#3 recd

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Posted 15 May 2018 - 10:28 PM

Atomos published a Youtube article in which Jeremy claimed that recording to the Shogun/ Ninja  with a Log Profile  was HDR. 



#4 Interceptor121

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Posted 16 May 2018 - 09:19 AM

Atomos published a Youtube article in which Jeremy claimed that recording to the Shogun/ Ninja  with a Log Profile  was HDR. 

As long as you record with the right colour space and don’t destroy everything using rec.709 this is exactly how it should work plus the monitor is HDR so you can see what you shoot within the limits of the gamma curve of your choice



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#5 bubffm

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Posted 17 May 2018 - 05:33 AM

Correctly exposed LOG footage is effectively HDR footage when you edit it in a BT2020 wide gamut timeline. Wether its recorded on an Atomos or inside the cam is irrelevant.

The Atomos of course gives you 10bit 60p at 4k, which you wo t get internally on any consumer type cam. But that does not change the fact that you got HDR-capable material if you filmed 10bit log.

#6 Interceptor121

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Posted 17 May 2018 - 11:03 AM

Correctly exposed LOG footage is effectively HDR footage when you edit it in a BT2020 wide gamut timeline. Wether its recorded on an Atomos or inside the cam is irrelevant.

The Atomos of course gives you 10bit 60p at 4k, which you wo t get internally on any consumer type cam. But that does not change the fact that you got HDR-capable material if you filmed 10bit log.

Not if you recorded REC.709 in that case the gamut is gone and the footage even if it can be made compliant is nkt HDR


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#7 bubffm

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Posted 17 May 2018 - 12:42 PM

Sorry interceptor, We are talking LOG. Log is NOT Rec709!  If you set your camera to record LOG you are recording HDR capable footage.

 

If you put LOG on a Rec709 timeline - then of course you only get an SDR clip as a result.



#8 Interceptor121

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Posted 17 May 2018 - 02:13 PM

Sorry interceptor, We are talking LOG. Log is NOT Rec709!  If you set your camera to record LOG you are recording HDR capable footage.

 

If you put LOG on a Rec709 timeline - then of course you only get an SDR clip as a result.

 

 

Sorry interceptor, We are talking LOG. Log is NOT Rec709!  If you set your camera to record LOG you are recording HDR capable footage.

 

If you put LOG on a Rec709 timeline - then of course you only get an SDR clip as a result.

You are right as it appears that the GH5 uses V gamut that is like or wider than Bt.2020

 

I guess the same reason why VLOG looks washed out makes also HLG look weird on a rec709 screen

 

Going back to the ops question you don't need to be shooting HDR effectively either VLOG or HLG are HDR capable or HDR ready I guess the issue is that with both neither the camera LCD nor the recorder screen if you use atomos are HDR so you don't really see what you are shooting


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#9 dreifish

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Posted 17 May 2018 - 06:32 PM

 

 

You are right as it appears that the GH5 uses V gamut that is like or wider than Bt.2020

 

I guess the same reason why VLOG looks washed out makes also HLG look weird on a rec709 screen

 

Going back to the ops question you don't need to be shooting HDR effectively either VLOG or HLG are HDR capable or HDR ready I guess the issue is that with both neither the camera LCD nor the recorder screen if you use atomos are HDR so you don't really see what you are shooting

 

The GH5 has a built-in display LUT for VLOG-L that restores some of the contrast. It's good enough (in conjunction with zebras and the waveform) to expose the footage correctly and get a rough idea of what the contrast range will look like.

 

In terms of where it could produce better results underwater (in terms of dynamic range), I think the backlit scenario is the most common. (I mean, how often are you shooting inside caves with the opening in frame?). This is a scenario I generally try to avoid shooting in 8 bit because the results never look good. Maybe with a log file you would be able to pull decent details in the foreground subjects, but my thinking is you'd need more than the 11-12 stops of dynamic range of the GH5. Maybe with a 14-15 stop cinema camera.

 

For sunburts, it theoretically isn't going to make much of a difference, since the sun is going to be blown out regardless. If you're exposing for the sunburst, the rest of the shot is going to be so many stops underexposed that ever 14 stops of dynamic range isn't going to save it.  Usually with photos, you need quite powerful strobes to get nicely balanced sunburst photos. 



#10 Interceptor121

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Posted 17 May 2018 - 10:18 PM

So what you are saying is that with the VLOG upgrade you get the option to set the screen in a reasonable way
On the other hand this is free for HLG with the screen help modes assuming you like them as is
I do have caves with the opening in the frames when you exit them more swim through then real deep caves it makes a nice shot


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#11 Darek Sepioło

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Posted 23 May 2018 - 03:20 AM

I produced 3 episodes for Discovery: Underwater Planet 4K HDR.

HDR trailer:

 

www.dareksepiolo.com



#12 wydeangle

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Posted 23 May 2018 - 03:39 AM

Darek,

 

Beautiful!

 

You may want to correct the typo at the end: DRGAON is probably meant to be DRAGON?

 

Tom



#13 Interceptor121

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Posted 13 June 2018 - 09:27 PM

To conclude @dreifish nobody produces HDR because there are almost no options to grade without specialised video hardware
Have spent some time on this and reached some conclusions will do some write up soon


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#14 dreifish

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Posted 17 June 2018 - 11:47 PM

I produced 3 episodes for Discovery: Underwater Planet 4K HDR.

HDR trailer:

 

www.dareksepiolo.com

 

Nice.. are these available for streaming online anywhere? Very curious to see the results on a true HDR display.


Edited by dreifish, 17 June 2018 - 11:51 PM.


#15 Interceptor121

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Posted 18 June 2018 - 12:07 PM

That YouTube clip doesn’t trigger an HDR flag on my Tv or on the iphone X
It does look good though!


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#16 Interceptor121

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Posted 22 June 2018 - 05:53 AM

That YouTube clip doesn’t trigger an HDR flag on my Tv or on the iphone X
It does look good though!


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Correction it does trigger HDR I just could not see it behind the logo


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#17 Pete L

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Posted 22 June 2018 - 05:12 PM

Sorry interceptor, We are talking LOG. Log is NOT Rec709!  If you set your camera to record LOG you are recording HDR capable footage.

 

If you put LOG on a Rec709 timeline - then of course you only get an SDR clip as a result.

Don't confuse BT2020 with HDR. They are not one and the same.

You can record and or deliver in BT2020 but if you want to deliver HDR then you must set your timeline to monitor and deliver an HDR compliant file.
 


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www.duai.com.au
 


#18 Interceptor121

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Posted 23 June 2018 - 01:06 AM

The requisites for HDR are in REC.2100. BT.2020 is one of the pre-requisites but not the only one.
In DaVinci I have seen that you can produce a file with BT.2020 colour space but without the corresponding transfer function in Final Cut Pro X the two things go together and the program uses the transfer function of source files to decide PQ or HLG.
If you shoot VLOG L on the GH5 you need a LUT to bring it into BT.2100 if you shoot HLG you don’t
In any case from what I am seeing is impossible to properly grade PQ without a reference monitor. HLG is much more forgiving


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Edited by Interceptor121, 23 June 2018 - 01:07 AM.

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#19 Interceptor121

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Posted 18 August 2018 - 04:37 AM

Sorry interceptor, We are talking LOG. Log is NOT Rec709!  If you set your camera to record LOG you are recording HDR capable footage.
 
If you put LOG on a Rec709 timeline - then of course you only get an SDR clip as a result.


Coming back to this am looking at VLOG files and they show as REC709 10 bit color sampling full color range

The LUT and other adjustments Panasonic provide are for REC709 this makes me think that the GH5 does not use V-Gamut but just REC709 colour space with compressed VLOG gamma. This gives higher dynamic range but narrower color space than HLG option


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#20 Lionfi2s

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Posted 18 August 2018 - 11:34 PM

Coming back to this am looking at VLOG files and they show as REC709 10 bit color sampling full color range

The LUT and other adjustments Panasonic provide are for REC709 this makes me think that the GH5 does not use V-Gamut but just REC709 colour space with compressed VLOG gamma. This gives higher dynamic range but narrower color space than HLG option


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There is a white paper out there for the VLOG-L have a look it gives all the details. Can't upload files here or don't know how to.


Edited by Lionfi2s, 18 August 2018 - 11:34 PM.