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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

HDR workflow

Eric Rainey

Eric Rainey

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I have to help give a presentation on HDR. Ha!

What I need to find out is...

What is the best format to deliver HDR? Prores, as far as I know, isn't HDR.

What is the best codec for compressing HDR? I have heard you can use H265 but you can't view it on a mac.

How would you view this on an HDR TV? Through a video card like Black Magic?...do they do that yet?

Any help or resource would be awesome!!!

Thanks
Eric
 
Which HDR TV are you plan on use?

In my understanding there isn't any 100% HDR TV exists (including OLED), but hopefully, we will see in few years.

HDTV (REC 709) has DR 7 STOPS (Black level 0.5 NITs to Peak luminance 80 - 120 NITs).
Anything (TV) above 7 STOPS is HDR

iPad (mini 4) can do 450 NITs (0.5 NITs Black) it’s HDR display
New iMac can do 400 NITs (0.4 NITs Black) it’s HDR display.

Currently, All the HDR TVs in the market are the total waste of money, They are using word "HDR" only for marketing purposes (including OLED, Oled is not the true black). They all show Peak Luminance value to confuse consumers (not Peak SUSTAINED Luminance - lol)

For example:
UHD HDR Peak luminance 500 NITs (black level 0.1 NITs) and
UHD HDR Peak Luminance 1000 NITs (black level 0.05 Nits)

above all is BS... Peak Luminance, meaning only 2 to 10% HDR window out of 100%)

In simple words.... Consumer monitor which says up to 1000 NITs, only mean 2 to 10% window will be HDR (lol)

However, Peak SUSTAINED Luminance, meaning it's all over 100% screen area, Guarantee Full HDR.
 
Eric Rainey said:
What is the best format to deliver HDR? Prores, as far as I know, isn't HDR.
Click to expand...
Sure it can. ProRes is just a container -- it doesn't define a color space or an amount of compression. 12-bit ProRes 444 could certainly do a fine job with HDR.

If I were you, I'd find a guy who's actually worked in HDR and have them come in and do the presentation. It's possible one of the local LA post houses would be willing to talk to you about it as a feasibility study, if this was a project you could potentially be bringing them. Dolby is another company that could potentially be willing to have a meeting with you, provided the project was specifically Dolby Vision.

I think the real question about HDR is what the market is going to be in the next few years, and how much it's worth in terms of increased post-production costs. There are a wealth of papers out there from SMPTE and the EBU on the subject, but most of them deal with the theoretical nature of it. PM me and I'll send you some tech reports, but be warned that they don't necessarily tell you how to practically pull it off, how much additional time and money it's going to cost, and how the workflow needs to go. For that, you really need a post house with a Dolby Pulsar monitor or an HDR projector (or alternately a Sony BVM-X300, which can do the lower levels of HDR).

Sony has a paper here on it:

https://pro.sony.com/bbsccms/assets/files/cat/mondisp/articles/HDR_X300_explained.pdf
 
Thanks for all your input! Marc, Kwan and Darek, I appreciate the help and the links! I have been asked to deliver an HDR project and people are trying to learn about it....probably for future projects. I am going to go to NAB this year and see what I can learn as well...


I especially love the insightful note from Jake...I wouldn't be asking the questions if I knew the answers....

Thanks again!
 
In addition to what Darien says above, here's some more...

The BBC and the ITU has some interesting papers on HDR and Rec2020:
https://tech.ebu.ch/docs/techreports/tr037.pdf
https://tech.ebu.ch/docs/techreports/tr037.pdfhttp://vmi.tv/training/useful-stuff/HDR_SURVIVAL_GUIDE
http://downloads.bbc.co.uk/rd/pubs/whp/whp-pdf-files/WHP309.pdf
https://www.researchgate.net/profil...yond_BT709/links/0deec52835fae506b9000000.pdf
https://www.itu.int/dms_pubrec/itu-r/rec/bt/R-REC-BT.2100-0-201607-I!!PDF-E.pdf


Spectracal has a good explanation of how it affects calibration and the monitor business:
http://www.spectracal.com/Documents/Understanding-HDR.pdf


SMPTE has quite a few good tech papers (some of which you have to pay for):
https://www.smpte.org/sites/default/files/2014-05-06-EOTF-Miller-1-2-handout.pdf
https://www.smpte.org/sites/default/files/Study Group On High-Dynamic-Range-HDR-Ecosystem.pdf


Dolby has a plethora of technical reports on HDR as it relates to Dolby Vision:

https://www.dolby.com/us/en/technologies/dolby-vision/ictcp-white-paper.pdf
https://www.dolby.com/us/en/technologies/dolby-vision/an-introduction-to-dolby-vision.pdf
https://www.dolby.com/us/en/technologies/dolby-vision/dolby-vision-whitepaper.pdf


Technicolor has several papers out there on their approach:
http://taniapouli.me/wp-content/uploads/2016/08/hdr_content_creation_siggraph2016.pdf


and there's some miscellaneous stuff:
http://vmi.tv/training/useful-stuff/HDR_SURVIVAL_GUIDE


It's fair to say HDR mastering is a very complicated process, and it all begins with a calibrated, broadcast-quality HDR monitor. That alone is a big hurdle to get by for most independent companies.
 
Eric Rainey said:
I have to help give a presentation on HDR. Ha!

What I need to find out is...

What is the best format to deliver HDR? Prores, as far as I know, isn't HDR.

What is the best codec for compressing HDR? I have heard you can use H265 but you can't view it on a mac.

How would you view this on an HDR TV? Through a video card like Black Magic?...do they do that yet?

Any help or resource would be awesome!!!

Thanks
Eric
Click to expand...

Prores422HQ was what Amazon was requesting for HDR10 deliverables a year ago (might still be the case). HDR is logarithmic, not linear (HLG and PQ). So any 10bit codec will work as a bare minimum.

To view HDR10 content on a consumer display, you could simply play the media in Resolve and output via decklink HDMI. But you would also need an HDR metadata injector inline to the consumer display (this will tell the display that the signal is HDR10 and to switch over to PQ).
 
ha ha tough audience
I have seen a few presentations where UHD / HDR is represented geometrically - as additional dimensions of color and resolution and dynamic range - very intuitive way to present to public audience
Sound like you should just present someone else's presentation with their permission and full disclosure that you are doing just that

Of more interest for this group would be HDR workflow to get R3D source into approved format for Netflix or Amazon HDR10 output.
Also what preview on set was sufficient to visualize the creative possibilities - at least 10bit but what nit output was required on set to visualize - or did they just highlight protect and trust they could get what they needed in post (for a successful HDR release to a studio).

Anyone willing to share?

Many people are hung up on the individual TV characteristics - but other than having a professional HDR capable monitor for grading, the output device should not impact the creative decisions on HDR grading. HLG provides less capability than HDR10 (or other more proprietary systems) but I would think the grades are all similar from HDR perspective.
 
There is no such thing as "shooting for HDR". All Red cameras as well as pretty much all modern cameras from other manufacturers, including film cameras can shoot material suitable for HDR delivery. So, there is no need to monitor images in HDR on set in order for that material to be used for HDR. Just shoot it as usual...
 
Mike Finegan said:
ha ha tough audience
I have seen a few presentations where UHD / HDR is represented geometrically - as additional dimensions of color and resolution and dynamic range - very intuitive way to present to public audience
Sound like you should just present someone else's presentation with their permission and full disclosure that you are doing just that

Of more interest for this group would be HDR workflow to get R3D source into approved format for Netflix or Amazon HDR10 output.
Also what preview on set was sufficient to visualize the creative possibilities - at least 10bit but what nit output was required on set to visualize - or did they just highlight protect and trust they could get what they needed in post (for a successful HDR release to a studio).

Anyone willing to share?

Many people are hung up on the individual TV characteristics - but other than having a professional HDR capable monitor for grading, the output device should not impact the creative decisions on HDR grading. HLG provides less capability than HDR10 (or other more proprietary systems) but I would think the grades are all similar from HDR perspective.
Click to expand...

I think that having a good HDR reference monitor on set could be helpful to cinematographers when they are deciding what ratios to use between talent, foreground, background, etc.. (especially light emitting sources in the background).
If the project is destined for Dolby Vision, then HDR is going to be the first pass done in DI and SDR will be secondary. So having optimal lighting ratios for HDR would make sense.
Might cause a DP to reconsider letting an element in the frame be clipped (clipped highlights and clipped gamut look horrible in HDR - personal opinion of course)
 
Paul Sage said:
I think that having a good HDR reference monitor on set could be helpful to cinematographers when they are deciding what ratios to use between talent, foreground, background, etc.. (especially light emitting sources in the background).
Click to expand...
You would really need a dark room with no reflections (like a black tent) in order to monitor HDR on set, and you'd need at least a custom LUT or an on-set colorist to provide the processing for the camera. This is not a "set and forget" adjustment -- HDR is a moving target that dynamically changes depending on scene content.

The problem with adjusting on set is there's a very real danger in getting so wrapped up in making the adjustments that you lose valuable shooting time. To me, you're better off just shooting a reasonable picture that you know can be adjusted or changed in post, and spend every minute making sure the creative work (acting, camera movement, lighting, focus, etc.) are correct. Don't worry about the color-correction or HDR this early in the process. At the same time, it never hurts to do tests beforehand so that you know what the limits are.
 
Would a black tent really be needed? For really dark scenes, sure a dim viewing environment would be optimal.
Not saying that the monitor would be used for color critical work. Just for eyeballing exposure or to see how colors at the edge of gamut look at high luminance levels (very different than 100nit SDR 709).

The monitor could just be used to verify that the lighting ratios are good. It's something that would probably be checked every once and a while, but once the cinematographer becomes accustom to how his lighting looks in PQ, the monitor wouldn't be checked as often.

Not saying that having HDR monitoring on set is necessary. I just think that it could be helpful in the pursuit of capturing an image that doesn't have to be tweaked a lot in post.
 
Paul Sage said:
Would a black tent really be needed? For really dark scenes, sure a dim viewing environment would be optimal.
Not saying that the monitor would be used for color critical work. Just for eyeballing exposure or to see how colors at the edge of gamut look at high luminance levels (very different than 100nit SDR 709).

The monitor could just be used to verify that the lighting ratios are good. It's something that would probably be checked every once and a while, but once the cinematographer becomes accustom to how his lighting looks in PQ, the monitor wouldn't be checked as often.

Not saying that having HDR monitoring on set is necessary. I just think that it could be helpful in the pursuit of capturing an image that doesn't have to be tweaked a lot in post.
Click to expand...

Remember your monitor has LED and these light will reflect by hitting back (on the monitor) from the front (color/white) wall.
Monitor setting can only be seen truly if you have surrounding lighting around 5 or less NITs (5 NITs is roughly about 16 Lux).

It same as Audio studio, when you record sound it hits the wall and effects your mic.

Note: 100 NITs (non-HDR) monitor seating 10 feet away from light color wall will reflect roughly 5lux
1000nit HDR monitor is 3 stop brighter (will reflect around 20 to 40 lux)
 
jake blackstone said:
I miss those days, when cinematographers would just use the light meter, experience and their imagination:biggrin5:
Click to expand...

Using sensitive spot light meter to bracket resolvable black, skin tone, and various highlights would work of course
As long as you knew range of eV the camera could resolve at each end
Regarding the (not yours) comment that film or red have so much dynamic range just shoot and sort it out in post is naive if taken literally -a blown out window is a blown out window and as people are noticing the highlight roll off can be different for sensors from same manufacturer
But yes I understand if you get perfect histogram you can be creative in post - but that histogram you select might be part of the creative process in extreme lighting
 
Mike Finegan said:
Using sensitive spot light meter to bracket resolvable black, skin tone, and various highlights would work of course
As long as you knew range of eV the camera could resolve at each end
Regarding the (not yours) comment that film or red have so much dynamic range just shoot and sort it out in post is naive if taken literally -a blown out window is a blown out window and as people are noticing the highlight roll off can be different for sensors from same manufacturer
But yes I understand if you get perfect histogram you can be creative in post - but that histogram you select might be part of the creative process in extreme lighting
Click to expand...

As you can see, in my post I used the word "experience". That is the crux of the whole process. In the old days people knew by heart how to correctly expose film. Now days, everyone is a cinematographer. And yet, somehow they still manage to blow the exposure regardless how many monitors they have on set. If you know your camera and you know how to read the light meter to be able to figure out your exposure ratios, you don't need to rely on in-camera LUTs and all those on-set monitors...
 
Paul Sage said:
Would a black tent really be needed? For really dark scenes, sure a dim viewing environment would be optimal.
Click to expand...
My experience of the last 40 years is that yes, you need a completely shielded room without any stray reflections or glare, which rarely happens on location unless you have a very well-equipped DIT/video village setup.

jake blackstone said:
I miss those days, when cinematographers would just use the light meter, experience and their imagination:biggrin5:
Click to expand...
I think a lot of DPs miss those days as well. The problem is that nowadays, they tend to get second-guessed when inexperienced producers or non-technical people look at a monitor and draw the wrong conclusions. At least in the film days, the director would turn to the cinematographer and say, "what do you think? Did we get it?" And if the DP nodded his head and said, "yes," then they'd move on to the next setup. Now, the director often won't take the DP's word and will insist on seeing playback and make ask for a retake for specious reasons. If the DP and director have a tight, trusting creative relationship, then it won't be a problem whether or not there's a monitor there.

To me, the only thing you should worry about on set is framing and focus, along with performance. The monitor is not going to lie to you about those things. Color, brightness, and contrast are all nearly-infinitely adjustable in post, and those are generally things that can be taken care of later. And those things are rarely visual details you can trust in a monitor dragged along on a shoot, particularly one thrown in the back of the grip truck every day and given very little calibration (if any).

I'm reminded of a shoot a few years ago where an actor accidentally knocked a matte box and an ND filter off the front of a camera, and I was able to save the shot and perfectly match the next frame to the point where they could stitch the two pieces together without a visible change. They had done multiple retakes afterwards, but none had the performance of the first one... and the fix wound up in the finished show. At some point, they have to trust the post people to do their jobs, provided the basic image capture is there and the histograms aren't completely slammed to one side or the other.

Worrying about HDR is totally silly, because anything can be jammed into an HDR dynamic range, including old movies made 50-60-70 years ago. You don't need to monitor it on set at all -- the information is already there. Just don't screw up the lighting and exposure -- follow all the basic rules of cinematography.
 
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