HDR ON or OFF?

[March Hare 720]

9 minutes ago, Chock said:

Yet another example of consumers being told 'you must have this function' so they'll race out and buy a new monitor, even when they don't actually know what HDR is. 🤣

There are quite clearly a lot of people who have absolutely no clue what high dynamic range actually is if they think you need a specific monitor to display an HDR image. It's true that a monitor designed to display HDR will probably make a better job of displaying extreme HDR content, but since the technique of creating HDR images dates from the mid-Nineteenth Century - a period when as far as I'm aware, there weren't many LED or CRT monitors kicking about - the notion that only a specific HDR monitor will be capable of displaying HDR, is quite clearly utter nonsense.

All an HDR image is, is a simultaneous composite display of more than one exposure at different aperture settings so that an image can replicate the wider range of detail a human eye with a pupil capable of dilating will see as it adjusts when looking about (aka saccades). That's it. HDR isn't some super-new concept.

This is 'Brig Upon the Water' by Gustave Le Gray, which is from1853. It is an HDR image...

Brig Upon the Water was created using what Le Gray called 'combination printing', but which we would nowadays refer to as the high dynamic range technique. It was made by doing two separate exposures of the same scene at different aperture settings and exposure lengths, a longer, wider one for the sea detail and a shorter stopped down one for the sky detail. The two were combined into a composite using the most detailed exposure settings of the two negatives for various areas of the overall image when printing onto the paper the image was finally displayed on. In essence, it is similar to the in-process 'dodge and burn' techniques which used to be common it darkrooms, where you'd use a cig lighter or a bit of cardboard to either brighten or darken a bit of the image whilst exposing it the negative through an enlarger onto photographic paper.

If you have a camera with an adjustable exposure setting, you can take an HDR image with it just as Le Gray did with his much more primitive camera; to use a digital camera to do that, you need a camera with either three separate CCD plates for R, G and B which can switch to taking three simultaneous composite RGB exposures at different aperture settings to make an HDR image of a moving object. For a still object or scene, you can simply take two shots at different exposure settings and then combine them to use the best detail of either for specific areas of the image. Photoshop, and indeed a few other image editing programs, can do this combination to HDR process for you (somewhat) automatically.

Or in other words, the basic ability for a monitor to display an HDR image has absolutely bugger all to do with whether it is 'an HDR one' or not.

Except you do indeed need a HDR capable display to see HDR10 content correctly. This isn't HDR as we used to know it; it's a specific technology, with not only higher contrast and brightness ranges, but also a larger colour shade palette. Trying to see HDR10 on a non-HDR TV, with the incorrect type of HDMI cable, through the wrong HDMI port, will look terrible - or at least not as it should.

[Glenn Fitzpatrick 3,799]

1 hour ago, Chock said:

 

Or in other words, the basic ability for a monitor to display an HDR image has absolutely bugger all to do with whether it is 'an HDR one' or not.

The reason why until recently digital cameras were not as good as film is that digital photos were limited to only 8 bit color (256 possible colors) and an 8 bit range of brightness, known as standard dynamic range (256 possible "shades of grey " ), whereas film is analogue with a theoretically infinite range of possible colors and brightness.

The whole issue with HDR is trying to overcome the limitations that digital processing place on vision which is actually an analogue phenomena.

Back in the day when I still had a darkroom I used multigrade papers that let you vary the contrast of the print (using color filters in the enlarger head)  and dodging allowed you to bring out detail in washed out bright scenes while burning did the same in dark shadow areas, details that a simple straight exposure would lose.  Film being analogue the missing information was on the negative you just used these tricks to bring the details out on the print. ( Your limitation with negatives on what you can retrieve is the grain of the negative and that is dependant mainly on the ISO of the film itself, high ISO film is more light sensitive but grainier)

With digital processing, that information is not just hidden - it is not even there at all, it is gone, kaput, lost forever. There is nothing you can do with an 8 bit dynamic range image to "recover" the missing detail, it was never saved, it is gone forever.  The NCIS television show scenes where they use computers to enhance missing detail in some shadowy blurred CCTV footage is just total nonsense.

As far as HDR goes on screens, it is mainly to do with:

• how many bits of color the electronics can decipher, the more bits the wider the range of colors
• and how many bits are available for setting light and dark - this is the actual High Dynamic Range feature
• how black the screen can go and how bright in nits the screen can go, this determines if the extra bits in the brightness info can actually be displayed by the panel itself
• whether that variation in brightness can be controlled at specific places on the screen (as opposed to lightening/darkening more general larger areas)

So ...  what you need to get a really good HDR picture is a device with electronics that can decipher signals with more bits of information and a display panel that can go from totally black (not just washed out sort of black) through to (with HDR 10) a full 1000 nits brightness on maximum at any given point on the screen.  You need both the right panel and the right electronics for this. Note that any panel using a single back light is NOT going to achieve this as the back lighting on these panels increases and decreases luminosity for the entire screen. it is not possible with a single CCFL back light to have some parts of the screen full brightness and other parts fully dark at the same time.  The other issue with a single CCFL back light is it will generally be white light which is going to wash out the color range.

An example of where the high dynamic range might be most noticeable is a bright sunlight beach scene with a child standing in the doorway of a shower block in the shade. The sun and sand should be bright and white the shadow behind the child should be pitch black but the child in the doorway should be clearly visible. This is simply not possible to achieve with standard dynamic range.

 

Edited July 8, 2021 by Glenn Fitzpatrick

[Chock 17,769]

7 hours ago, March Hare said:

Except you do indeed need a HDR capable display to see HDR10 content correctly. This isn't HDR as we used to know it; it's a specific technology, with not only higher contrast and brightness ranges, but also a larger colour shade palette. Trying to see HDR10 on a non-HDR TV, with the incorrect type of HDMI cable, through the wrong HDMI port, will look terrible - or at least not as it should.

Yes, a specifically capable HDR monitor will handle HDR 10 content better, but the point I was making is that people were saying an normal monitor cannot display HDR, which is simply not true.

The wider point was that much of this is about trying to sell you a new TV, so it's: 'You've gotta have a flat screen instead of that curved CRT, then the next minute it's, what? you've got a flat screen? Nah, you need one of these new curved ones!'. Same with phones, first they were obsessed with trying to sell you the smallest one they could make, even having them fold in half, now they're tying to sell you something which barely fits in your shirt pocket, or they sell you how great a car handles, then try and get you to buy one which drives itself lol. People swallow this stuff often without thinking about it or even knowing what the functions which are being pushed on them actually do, or whether they really want them.

MSFS already does the main effect of what HDR is trying to simulate on a standard monitor by default, i.e. it replicates the light dazzle effect you get when you look outside cockpit where little in the way of detail can be seen at first after having been head down looking at the instruments, owing to your pupils being too dilated for the change in light level as you look up, but then shrinking to give your retina a suitable light level to be able to pick out detail. You can try this on your standard monitor and you will see this effect take place in MSFS. You will see it is the same effect as when you look down at a bright pavement in strong sunlight, where it initially is so bright you can't make out any detail on the ground, but after a second or two, you start to see the detail.

Larger colour palette capabilities are fine, but sRGB can already display about 17 million different shades, whereas the average male human can only distinguish between about 12 million of them, and worse, ten percent of all males will actually have some form of colour-blindness too. Not all males are like this, some have better abilities, but generally speaking women have a broader ability to distinguish colours and will typically be able to distinguish more of those 17 million different colours than the average man. So for a very large portion of the male population, that broader range is fairly pointless. This is simply the way things are with humans; it's the way we evolved, where men's eyes were evolved to pick up movement; so they have better peripheral vision than women because that is useful when hunting. Women evolved to have better colour perception because that is useful for gathering. These traits mattered when we were hunter-gatherers in ancient times, and we are kind of stuck with them thanks to evolution.

Edited July 8, 2021 by Chock

[Glenn Fitzpatrick 3,799]

7 minutes ago, Chock said:

Not all males are like this, some have better abilities, but generally speaking women have a broader ability to distinguish colours and will typically be able to distinguish more of those 17 million different colours than the average man. So for a very large portion of the male population, that broader range is fairly pointless. This is simply the way things are with humans; it's the way we evolved, where men's eyes were evolved to pick up movement; so they have better peripheral vision than women because that is useful when hunting. Women evolved to have better colour perception because that is useful for gathering. These traits mattered when we were hunter-gatherers in ancient times, and we are kind of stuck with them thanks to evolution.

Which explains why the women I know have a whole range of colors they see which are named after food whereas I just see "brown" or "green" I suppose. 

For me Pumpkin and Apricot and Tangerine and Mushroom and Avocado are types of food not colors. Apparently this means I am color blind 😄

[GCBraun 2,399]

On my LG CX OLED HDR works extremely well both on Windows and on MSFS. The image quality is also much improved with HDR on, so there is no need to turn it off for me. G-Sync, on the other hand, leads to weird screen flashes probably caused by my second monitor, so I have to turn it off.

[Bandyka 75]

19 hours ago, FlyBaby said:

Trying out the EPSON LS500...

So your eyes could tolerate the OLEDS...much like a projected image?

The LS 500 is nice , its low contrast (black levels) high brigthnes so it will do fine in a  non dedicated room with light control.  (I used to have the LS10000 laser I loved it) Yes I did like the OLED in the cave very much but even at 65" it was tiny as 🙂

[Bandyka 75]

Funny how I still see people waking up to the wonders of HDR after being available for 5 years or more 🙂 Still very few understands how it works and what is required. I've been working out its quirks since day one and been through all its hoops and a million displays. Only now  that displays are properly capable of displaying it and content is well mastered for. FS is pretty awesome in HDR.

 

This is how I fly. Just love it.

 

 

 

[Chock 17,769]

On 7/8/2021 at 7:55 AM, Glenn Fitzpatrick said:

Which explains why the women I know have a whole range of colors they see which are named after food whereas I just see "brown" or "green" I suppose. 

For me Pumpkin and Apricot and Tangerine and Mushroom and Avocado are types of food not colors. Apparently this means I am color blind 😄

What it all means is that if two blokes turn up at a party wearing the exact same style black suit, they look at one another, probably let on, and then think, 'hmmm, seems I got it right', whereas if two women turn up at a party in the same dress, there is going to be a fight.