HDMI max length for Projector 1080p / 4K

pioneer2000

pioneer2000

pioneer2000

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Just setup my projector (Optoma HD25e) after a year in storage... though discovered that my previous HDMI lead isn't long enough for the new room (I think it's a 10m lead but need 15m or thereabouts).

Now i'm aware that HDMI isn't technically supposed to work over such long distances but the 10m one always worked fine at 1080p, so guessing 15m should be ok?

I wanted to future proof by getting a HDMI 2.0b / 4K compatible cable (now I realise a lot of it is snake oil but there are definitely some quality differences at these sort of distances, in the budget HDMI arena).

In doing some research it seems that HDMI 2.0 states a maximum of 3m for 4K HDR... so how on earth do people wire up 4K projectors with only 3m to play with?

I'm guessing there's no way to get a cable that would definitely work at 15m if I ever went 4K?
 
So essentially none of the cables I'll find on Amazon (at a reasonable price) will work at 18Gbps (4K HDR 60hz) and I might as well just buy any old one that will work at 1080p at 15m and forget about future proofing if I ever buy a 4K projector?
 
Does anyone know if Redmere limits the bandwidth that the cable can transmit? i.e. If the Amazonbasics cables are only the 10Gbps version of Redmere, does this mean that's all it can transmit, or could it still work at 18Gbps despite the limitations of the chipset?
 
Chris1712 said:
To be fair how often are you going to be feeding 4k60 HDR 4:4:4? Pretty much never, maybe try and future proof the cable run at least with some plumbers tape or something but for now I assume 24hz is all you need which I bet a lot of cheaper cables will manage. 4k60 HDR from consoles is 4:2:0 anyway (afaik?).
Click to expand...

Sure, likely 4K 60hz from my X1X is the max id put through it... what bandwidth does that equate to then? Has to be more than the 10Gbps that any standard hdmi cable can do over 15m?

I’ve got a RedMere cable coming (was too late to cancel it) so can test tonight. If I connect my X1X direct to my LG B7, the 4K test screen in the dashboard should indicate if it’s all working, shouldn’t it? (I’m thinking 4K, HDR and all the jazz that it lists ticks by in that menu)?
 
I'll test out this Redmere cable tonight, my concern is that if it is a 10Gbps Redmere chip, will it limit the signal to that? I.e. if the cable can actually cope with >10Gbps, does the presence of the slower chipset in the cable restrict the signal transmitted?
 
Right, well it seems that this Redmere lead won't work with Dolby Vision weirdly.

4K 60hz on X1X with Red Dead 2 works fine. Try to open Netflix (4K Dolby Vision) and it just displays a black screen.

Switch back to my amazonbasics bog standard hdmi lead (1m) and it all works fine again.
 
Seems that way...!

It's amazon so i'll get a refund but just goes to show the Redmere cables aren't up to much.

Ordered a 12.5m CSL high speed HDMI instead... so I will abandon the future proofing and just run it with my 1080p projector. For the fun of it I'll see if that cable can do 4K Dolby Vision as well!
 
Potentially stupid question but is Netflix on the Xbox running at 4K 60hz Dolby Vision when purely in the menu...? I'd have thought it would be a 24hz?
 
pioneer2000 said:
Seems that way...!

It's amazon so i'll get a refund but just goes to show the Redmere cables aren't up to much.

Ordered a 12.5m CSL high speed HDMI instead... so I will abandon the future proofing and just run it with my 1080p projector. For the fun of it I'll see if that cable can do 4K Dolby Vision as well!
Click to expand...

Well this CSL cable won’t even display an image at 4K, so definitely no luck here. Going to use this for 1080p on the projector and scrap the future proofing plan. Christ knows what cable one needs to get 18Gbps over that distance!
 
I wasn’t particularly surprised (I said I’d simply test it for interest sake). I would have hoped it’d be able to produce something more than just a black screen (it’s claimed to be 4K 30hz compatible).

I’m still unsure what people use for long runs at 18Gbps (I.e. 4K, Dolby Vision, 60hz)... seems no standard HDMI cable can do that. Maybe Spectra7 cables or CAT 6?
 
It's only a cable though for heaven's sake... with how common 4K projectors are nowadays you'd have thought an affordable cabling solution would be available.
 
Lol, you seem to be taking this personally!

Manufacturers make many wonderful electronics yet it simply seems that buying a cable for a 4K projector is next to impossible without calling in all manner of experts and charts of specifications etc.

I’m surprised that Optoma and the like don’t do bundles with the leads included as it’s almost impossible to determine what will actually work perfectly.
 
I think the problem is more so the confusion created by the lack of clear standards.

If I search on Amazon for a 15m hdmi 4K cable and a whole list of appear in the search, I believe that they should work regardless of the price. It’s not for the consumer to figure out if the advertising is false or not.

At the end of the day if a digital cable works it works. I don’t care if it’s braided or has gold coloured connectors etc (that many of these “expensive” cables feature). So obviously I’ll look for the cheapest variant I can find. The trouble is that nobody (cheap or expensive) make it easy to tell if the cable is compatible because the standards are so convoluted.
 
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