GH5 SDR, HDR, HLG, color spaces, dynamic range

Here is a very good study of different color spaces. It has an interesting table of contrast ratios.

Keep in mind that this chart is almost 4 years out of date and a h*ll of a lot has changed with the mid to lower end gear since then.
 
Keep in mind that this chart is almost 4 years out of date and a h*ll of a lot has changed with the mid to lower end gear since then.

Yes but it has many interesting values like DR in eye 6.5 stops simultaneously or 20 stops in general. Also film recording / film projection very high value is a surprise. I dont remember seeing good contrast or vivid colors in cinema. How can a cinema image has 13 stops when the max brightness is 48nits and blacks gray. How the cinema colors space DCI-P3 can have vivid colors when the image is generally very dim.

Also the 16 stops of old good CRT TV is a surprise. I remember comparing my Philips CRT tube TV and my Samsung top model plasma TV side by side and the CRT Philips had much higher visible contrast.
 
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Those projector stats are bogus. A projected film positive doesn't have more DR than the original negative.

Milky blacks and 14ftl of light can't represent 16 stops.
 
GH5 HLG is stored in rec2020 file. It is a very large color space and no monitor or TV can show its most vivid colors. The Gh5 HLG file looks very muted when watching with rec709 display. I wonder if the GH5 HLG file tries to grade vivid colors somewhere between rec709 and rec2020 and not recording color values near max values. The HLG file watched with rec709 display needs much added display saturation adjustment because the color values are not near the max in rec2020 file. It is like a rec709 file recorded with saturation -5.
 
I watched the new Star Wars in big premium theater with Barcos newest 4k laser projector. The projected image was quite bright but the contrast was poor. The black level was "gray" and colors has no vivid DCI-P3 look. My rec709 TV has better contrast and more vivid colors. The theater has* very black interior so the poor black level comes from projector. I think the visible contrast ratio was way lower than 1:1000.*Surprisingly the 4k image quality was also noisy, something like GH5 iso3200 look. I think they have added tons of film grain because the IQ cant be so noisy otherwise. It may be some kind of retro thing.

Dolby Atmos was good but very loud. Explosions sounded*realistic and my fingers went to my ears automatically in some scenes. Everything was too loud and the otherwise pure and good sound distorted in my ears. Even dialogues was unpleasant and hard.
 
Dolby Atmos was good but very loud. Explosions sounded*realistic and my fingers went to my ears automatically in some scenes. Everything was too loud and the otherwise pure and good sound distorted in my ears. Even dialogues was unpleasant and hard.

Slightly off topic, but this is why I’ve stopped going to the cinema, it’s fair too loud these days and ruins the experience.

I’ve tried HLG stuff and your right, it’s got a odd look to it on a normal tv. Shame
 
Slightly off topic, but this is why I’ve stopped going to the cinema, it’s fair too loud these days and ruins the experience.

I’ve tried HLG stuff and your right, it’s got a odd look to it on a normal tv. Shame

That - and when its too quiet. Because the trailers are mixed loud, with constant booms, the theaters turn down the volume, which makes the main feature too quiet (when it finally starts). There is supposed to be a standardized loudness system. Other than a sneaky way to get a high dynamic range acquisition format into low cost cameras, HDR makes little sense as a display format. I like low DR.

https://prolost.com/blog/hdrtv

*By the way, the local independent theater shows only a few trailers at a reduced volume before the feature. (10 minutes vs 22+)
 
I really appreciate a lot of Stu's opinions - but he's wrong about this one. He's throwing out the good because he's afraid of the bad. Good HDR, intentional HDR (director, cinematographer, colorist), can look amazing. It's a bigger palette for an artist to work from. Not every color should be used in every painting, but it's nothing but good to have the choice.
 
I really appreciate a lot of Stu's opinions - but he's wrong about this one. He's throwing out the good because he's afraid of the bad. Good HDR, intentional HDR (director, cinematographer, colorist), can look amazing. It's a bigger palette for an artist to work from. Not every color should be used in every painting, but it's nothing but good to have the choice.

That's a good point; I'll need to revisit my impression of HLG.
I, like Stu, am an old-school sucker for low contrast and 24 fps (series of unreal paintings)
 
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