BenQ TK850 4K & DVR issues.

[Stumacdon 1]

Hi all. Please bear with me with this, I'm reaching out because I'm not sure where the issue lies.

I have a Virgin V6 connected to the BenQ viahttps://www.amazon.co.uk/dp/B01D2R0C1E?ref=ppx_pop_mob_ap_share cables.

I have tried every combination in the Video Output settings of 1080p, 1080p passthrough, 2160 and 2160p passthrough and also Auto Detect.

Regardless of which option I choose, I either get....

No Signal Detected (when on 4k channel).
Intermittent flickering.
A pure green screen or a flickering green screen when selecting 4k content on Amazon / Netflix through V6 box.
A screen refresh which brings up the resolution status in the corner.

I cannot for the life of me have a setting which works seemless between 4k, HDR, regular HD and Amazon / Netflix content.

The only setting which doesn't cause an issue is when I only have 1080p option selected, but of course I then don't have 4k which is kinda important

My question is, is it the V6 box setting, the HDMI cables or the projector?

Any questions or suggestions appreciated, it's driving me up the wall.

 

[pd2444]

From your description I'd say the HDMI cables. The data rate at 4k is way higher so when you switch to that the projector is losing the signal. Cables which are fine at 1080p can easily fall over at 4k.

Only way to be sure is to try another cable, or a shorter one, and try to eliminate it as the fault.

 

[Stumacdon 1]

From your description I'd say the HDMI cables. The data rate at 4k is way higher so when you switch to that the projector is losing the signal. Cables which are fine at 1080p can easily fall over at 4k.

Only way to be sure is to try another cable, or a shorter one, and try to eliminate it as the fault.

Thanks, I have been wondering if that could be the cause, but you'd imagine cables sold at that length and advertised as 4k would be able to handle the bitrate of 4k over that length. That 12.5m is the shortest I can get away with for the size of my room (obviously I can buy a 1 /2m cable to test) so any recommendations would be appreciated

 

[Stumacdon 1]

From your description I'd say the HDMI cables. The data rate at 4k is way higher so when you switch to that the projector is losing the signal. Cables which are fine at 1080p can easily fall over at 4k.

Only way to be sure is to try another cable, or a shorter one, and try to eliminate it as the fault.

Do you think either of these should do? Seems the ones I bought previously only went 30hz, this goes 60hz (in theory)

Amazon product

Or

deleyCON 12.5m (41.02 ft.) HDMI cable - compatible with HDMI 2.0a/b/1.4a - UHD 4K HDR 3D 1080p 2160p ARC PoE - High speed with Ethernet - white on OnBuy

deleyCON 12.5m (41.02 ft.) HDMI cable - compatible with HDMI2.0a/b/1.4a - UHD 4K HDR 3D 1080p 2160p ARC PoE - High speed withEthernet - white ...

www.onbuy.com

 

[pd2444]

You definitely need one which does 4k 60Hz as that's the rate Netflix, Amazon etc use.

On the face of it your original one looks ok but HDMI cables seem a constant source of problems and are the cheapest and easiest thing to try first. The fact that 1080 is working and 4k isn't certainly points towards a signal loss somewhere and something in the chain not being fully compatible.

 

[Stumacdon 1]

Yeah the more I think about it the more certain that is the issue. So I've bought some 2.1, 48gbps, 2m cables which (claim) to display 4k at 130hz and will move the V6 box closer to the projector which negates need for long cables.

Fingers crossed

 

[SGRG]

@Stumacdon 1 did that fix the issue? Having the same problem, would be good to know if that fixed the problem. Thanks

 

[Stumacdon 1]

It seems like upgrading my hdmi cable to a shorter length and depositing it worked perfectly. Thanks to those that gave me a one of those obvious in hindsight answers

 

[SGRG]

It seems like upgrading my hdmi cable to a shorter length and depositing it worked perfectly. Thanks to those that gave me a one of those obvious in hindsight answers

thanks for the update. Glad it’s resolved for you. I don’t have an option to go with short hdmi due to position of the projector (ceiling) to where the source is. I am looking at 10meter 4K hdmi cable:
Ultra HDTV 4K HDMI Cable - 10m Premium HDMI 2.0b Lead, High Speed with Ethernet at 18 GBps, supports [email protected],

Hopefully does the trick.

 

[bobbybuilder59]

I've noticed Benq tk850 isn't handling 23.976hz content very well ie frame dropped every 40 ish seconds. On doing a bit of research I found this.
Colour Wheel Speed
2D: 96Hz; 100Hz; 120Hz

3D: 120Hz
So 96hz is great for 24hz video, 4x24= 96. But 4x23.976= 95.904, hence a frame dropped every 40 seconds,
Am I correct in this? Would love to hear from someone with more knowledge than me..

 

[bobbybuilder59]

Have been in contact with Benq support and they have confirmed to me that this projector cannot play 23.976hz property without a frame skip every 43 seconds as it will play it at 24hz. And confirmed no fix for this model but will look into it for future models.