Cat5/6 question.

Final update, I’ve changed my last two remaining cameras to 1080p ones so that makes 4 X 1080p cameras in total - that’s 4K isn’t it? They have a wider field of view too so a better view all round. The 15m HDMI cable was about a foot short to reach my DVR which was on a shelf about mid-height in the loft. Not too much of a problem as had I planned to move it to the loft floor where it’s a few degrees cooler in summer! The heat on a very hot day a couple of years ago cooked one dvr so I've been turning it off during the hot spells.

I’ve got to say though, I’ve experienced zero buffering on iPlayer, catchup, Netflix, Prime and kodi on the fire tv since hard wiring them and the remote access to the CCTV has been 100% too. Very pleased with the results and thanks to all those that gave advice.

Mottie said:

Final update, I’ve changed my last two remaining cameras to 1080p ones so that makes 4 X 1080p cameras in total - that’s 4K isn’t it?

Click to expand...

It doesn't really work that way. When on multiscreen view (2x2, 3x3, 4x4 etc) the DVR scales the source signals to fit inside at 1080p window. The output from the DVR, which is what's going down the HDMI cable to your TV, is always 1080p unless the DVR is capable of outputting at a higher resolution. If it's always 1080p, the signal will stay within the bandwidth limits of the cable. Where the DVR is capable of outputting at say 4K UHD (2160p), then it wouldn't matter what resolution the cameras were, their images would be scaled up or down to fit the output window of the DVR. That's the point where you'd hit the limits of what the cable was capable of carrying.

For example, you could have 4 x 720x576i (standard def 16:9) cameras. In a 2x2 window on a 1080p res screen you'd see each camera at its native resolution. When going to full screen @ 1080p for viewing a single camera then the source signal would be up-scaled from 576 up to 1080p.

Say you had 9x 1080p cameras arranged for viewing in a 3x3 grid. Based on your idea, that would give a total pixel area on screen as 5760 x 3240, or 1.5 times more pixels than 4K UHD. There isn't a 4K UHD TV made that would understand that signal resolution, so even if you had a 15m cable capable of carrying it, the TV wouldn't be able to display the results. This is why the DVR does a rescaling job.