Cables - HDMI or Component (1 Viewer)

[Dave1]

Trying to get a handle on this HDMI format. The ?'s I have are. (1) Is HDMI the only one that will carry the digital signal for A/V?
(2) Will component cables carry 1080i, is that the limit?
(3) How much better is HDMI to component? ( Video part )
(4) Is 1080i alot better than 720p?

I thinking about installing a ceiling projector and when I had the house built I had them install the cables in the ceiling ( component, cat5, cable, No HDMI )

Tks Dave

 

[Bob McElfresh]

Hi Dave.

(1) HDMI carries both the video and audio in a digital format format. DVI carries the same video in digital, but not the audio.

(2) Component cables carry analog video signals. Since both 1080i & p top out at about 35 Mhz - any HD-rated set of component cables works great for both. Component cables CAN carry higher-frequency signals, but video engineers like the cables to handle 3-4 times the max expected frequency to avoid some artifacts.

(3) The video signal and quality is the same. The connection type does not limit the information.

However: HDMI has a slight edge over Component. This is because the component cables usually mean your source takes a digital signal, convert to analog for the cable. Then your television converts the analog to digital to 'play' with the signal for display. The extra Digital->Analog->Digital conversion can introduce artifacts.

HDMI stays digital so there is less conversion/electronics and a reduction in artifacts.

(4) Is 1080i a lot better than 720p - There was a lot of questions over this a few years ago. I believe it became a "coke vs pepsi" issue with no real winner.

 

[Cees Alons]

Well, to reply to that last matter...
Picture quality is determined by a lot of things and resolution is an important part of those.

Most of the modern TV-sets can handle better horizontal resolutions than necessary for common NTSC or PAL. (As a result you may see a significant improvement already when playing 720- or 1080-lines material on a common TV-set, at 480 vertical lines.)

Of course that will even significantly improve if you go to real 720 lines material on a 720-lines display and again if you step up to 1080 vertical lines. So, in principle, the answer to your question is: yes, 1080 vertical lines (and the accompanying horizontal resolution) are significantly better than 720 vertical lines. The improvement factors (480 -> 720 vs. 720 -> 1080) are the same!


However here are some caveats:

(1) Does the TV-set really display full 1080 resolution?
Many "HD-Ready" TVs do not have 1920 x 1080 screens.

(2) How big is your display and how far from it are you sitting?
If you're sitting relatively far away from a relatively small TV-screen, a 1080-image on your retinas may hardly have a better resolution than the 720-image on the retinas of someone sitting closer to a somewhat bigger screen.

(3) How does the TV-set process the incoming image signal?
Some TV sets (many actually) do not process 1080p signals "properly": they convert it to a lower resolution first and then "upgrade" the image to 1080 vertical lines. (It is said that some other TV-sets do the same for 1080i, but actual info seems missing).
If you're going to buy a projector for HR movies, make sure you buy one that can do *real* 1080i and 1080p stuff. On this forum you will find very positive reviews of buyers of the new Sony Pearl (VPL-VW50), which seems to be just under $5000. I ordered one of these myself, but I didn't receive it yet, so I cannot tell you from own experiences if the're right.


Cees

 

[Dave1]

Thanks for the great info.

Dave