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I watched this a few weeks ago - itās really good. Another example of technical limitations imposed years ago lingering well past their use by date.
Iāll have to dig one out of the shed, sure I had oneā¦
Thatās rather interesting, thanks for sharing. I started calibrating my monitor several years ago, mainly due to wasting lots of ink and paper. Even after calibrating and getting icc profiles from the paper manufacturers I still canāt get things quite right. Now I think I know why!!!
What does he suggest to use instead? DisplayPort?
One thing about this still baffles me ā¦ and thatās that the cable restricts the number of bits?
Iād have thought the number of bits is dependant on the source / destination ā¦ and that a dumb cable is just the transport.
How?
Or - are they just describing this badly and really saying that itās the protocol varies?
The protocol supports full bit depth but they truncated it in the protocol chip in the early days to match cable/technology limitations at the time. Those limitations no longer exist but the industry āforgotā to switch the chips back to full spec, because it didnāt matter for TVās which is the bulk of the market, so itās crippled. At least thatās how I understand it.
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Would this just be an issue at the source end? Or could it be an issue if just at the destination?
Everything I use is relatively modern - except the TV (2008). Iāve certainly not seen any issues or difference between whatās on the laptop screen and the TV.
I wonder how Iād check the TV?
Honestly canāt remember, I last looked at it about 15 years ago, HDMI 2.1 had just come in. The problem is thereās so many variations itās difficult to tell - active cables, passive cables, copper cables, fibre cables, HDMI 1.4, 2.0, 2.1, 2.1A then on top of that the manufacturers add meaningless marketing bollox terms like High Speed, Ultra High Speed on and on. SD cards suffer from just the same miasma of confusion and obfuscation rant rant moan moan.
Anyway, youāre unlikely to see much of an issue for watching telly or general laptop/monitor use but it is an issue for critical viewing situations like colour grading, pro photography & print or multiple camera matching for broadcast or cinematography. When I was doing this sort of thing we used SDI outputs from the cameras to record at 4:2:2 or 4:4:4 or monitor on very expensive broadcast quality monitors. Modern HDMI properly programmed by the firmware will support this but check carefully - Displayport (and SDI if youāre nerdy enough) will definitely be ok as will Thunderbolt/USB-C I believe but Iād have to double check - certainly Thunderbolt works into Apple Cinema monitors for example.
ā¦ which was where I thought there may be an issue for me ā¦ since I sometimes have my laptop linked via HDMI to the TV as an extended desktop for when using Davinci Resolve.
Usually only the scopes/histograms and other tools, rather than the graded image, on the TV ā¦ but sometimes the other way around.
Of course, using the TV for the histograms/scopes has absolutely no impact on the grading (they could be in B&W - if you know which is which - and get the same result).
Iāll have to play moving things between the two to see if thereās an impact. I think there wonāt be - since I like the grades whichever Iāve been using.
I will find the video explaining some of this but if I recall itās about colour spacing between 0 and 255.
HDMI is between 16 and 235 for easy transmission which means everything below 16 and above 235 is lost.
I obviously donāt know if while grading, the editor software is stretching the HDMI video to fill the range 0 - 255 while in fact itās 16 - 235ā¦.
I looked at the back of both my monitors the gaming one has got a Display Port but the other which is just PC display hasnātā¦.
I split screen using the 4K gaming one to set the white balance and while scrubbing, to do this though I have to render the Cinelike first to decode H264-265, something changed after an updateā¦
Updates arenāt always your friendā¦.
Looks like Iāll be experimenting and possibly upgrading to a Gaming Monitor to replace the bog standard oneā¦
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I did some testing of my old TV, and pretty happy itās not screwing with the HDMI from the laptop.
Neither will be displaying cutting edge colours - but they are both doing the same thing - and thereās no HDMI between laptop and its own screen. 
When you say old, how old, is it tubes old or LEDā¦
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As above, somewhere, 2008 ā¦ but a Samsung LED.
Itās most likely me but I can never get the white balance correct off my LED display, itās getting on in years now. Do LED displays age?
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In the days of āTV showroomā, when 100 screens were showing the same video ā¦ they never even start the same by a million miles. 
Googledā¦.worth a read.
Got all the time in the world (usually) for Glyn as a fellow Brummie living the good life down south, but his more recent stuff is clearly paid partnership stuff, which is when I start paying less attention to peopleās output on YouTube as it becomes less objective and more biased towards manufactures, whether they be monitors or printers, but itās still a decent video none the less.
Itās given me food for thought, Iāve ordered 2 x VESA conforming Display Port cables off Amazon for experimentingā¦. Playing withā¦
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