[dsmith6281]

I've got a samsung sir-ts160 (3rd one actually) and a samsung hln617w. i've seen many comments here about how DVI is the best connection. While i do see a somewhat sharper picture, i seem to notice other issues with DVI. this is my third samsung STB. First one (with the panny DLP) gave me strobing (different from the flickering) - Panasonic blamed samsung but i didnt beleive them and got rid of the problematic set anyway. Now with the samsung set, one stb gives me a problem where the bottom few lines of the screen seem different from the overall image - as if they were repeats of other scan lines. very strange. sent that back and the next one doesn't fill up the whole screen (even when center adjustments are made). and 4:3 images seem blurry at the bottom.


is this the best to expect from DVI? or is this a samsung quality issue?


D

 

[Randyhat]

I don't think it is necessarily overrated but it is far from the be all and end all of system connectivity. I have a Samsung hln467 dlp and am using both DVI and high quality component cables connected to my SAT receiver. When I switch between the two I am able to tell no difference. There is so much more to picture quality than the type of connection. There is no substitute for good quality components at either end of the connection, whether it be DVI, component, or composite. All things being equal, i.e, the same high quality components with both DVI and component connections, theoretically, the DVI might be better. However, things are seldom equal and a DVI connection on a cheap $200 DVD player does not make a silk purse out of that sows ear. The development of DVI connectivity had much less to do with enhancing picture quality than it had to do with issues of copy protection. The fact that many Samsung owners on this forum chant the DVI mantra may be a function of quality of the digital circuits relative to the quality of the analog circuits on their particular sets rather than the superiority (on absolute terms) of DVI. Again, this has not been my experience. Trying to tell the difference between DVI and component on my set reminds me of trying to tell the difference between the sound of two high quality audio cables. Sometimes I think I hear a difference, sometimes I don't.


Regarding your issues with DVI connection problems. I have occassionally seen some "activity" on the top of a 4:3 picture but have not noticed any of the bluriness you mention. On full (wide screen) mode the picture is stunning and flawless.

 

[Art Lloyd]

DVI isn't for us. It's for the content owners. Art

 

[DLR]

Excellent point Art. I thought DVI was developed strictly for copyright protection. I also have the SIR-T160 and have not noticed any significant difference between the DVI and component connections.

 

[PooperScooper]

Art is correct, but DVI *with HDCP* (DVI/HDCP) on a stb is for

content protection, even though no provider is flagging content

yet. DVI itself has nothing to do with content protection. DVI output

of HTPC, DVD players, and scalers into digital displays is where

DVI usually provides bigger "bang" in PQ. In this case, HDCP may

or may not be employed.


larry

 

[PooperScooper]

DLR,

DVI was developed for computers sending video data to a digital display.

HDCP came along later. Encryption works well with digital data and

DVI provides that transport. (DVI can also send analog video)


larry

 

[John Mason]

Greg Rogers, Widescreen Review's video technical editor, goes into DVI performance with two articles in WSR's October issue. (A while back he was a guest commentator in another forum here.) One article deals with DVI in general, the other reviews the new Samsung DVD-HD931 DVD player that has DVI outputs.


In general, his conclusions seem similar to Randyhat's above: DVI enhancement isn't a sure thing, and non-DVI component-only quality varies. Rogers points out that DLP displays maintain an all-digital signal/display path with a digital source. (DLPs/DMDs/micromirrors use digital pulse width modulation to control each micromirror.) He also explains that using a DVI source eliminates one digital-to-analog (DAC) conversion stage, which can benefit image quality. Analog signals fed to a DLP display must be converted into digital form with an analog-to-digital (ADC) converter, potentially creating other problems that he outlines.


"The most common picture artifacts created by the video DAC system are edge outlining and ringing," he writes. "These artifacts are the potential consequences of digital and analog filters." He used the sharpness pattern on the Avia DVD for tests, indicating fewer artifacts with the Avia sharpness pattern translates into better DVD movie performance.


Both articles concentrate on DVDs and DVI. He mentions many newer CRT RPTVs digitize analog input signals for scaling and other processing. -- John

 

[Art Lloyd]

Someone tell me why DVI and not Firewire, other than copy protection. Firewire connections between a Samsung 151 stb and two DVHS recorders seems so great at my house.....Art

 

[PooperScooper]

There is a form of copy protection on firewire, it's called "5c" or something.

It's used between DVD-A/SACD players and processors.


I don't know the exact answer but cable length, electronics cost, and

copy protection issues could be involved. Plus, heaven forbid

that one universal media connect multiple devices from multiple manufacturers ever become "standardized".


larry