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Discussion Starter · #1 ·


I have a Panasonic DST50/PV-HD1000 fed from a Dish 5000

with HDTV modulator. So I can get HBOHD, as well as

off-air DTV from my outdoor antenna. TV is a Sampo.


In Dallas, ABC, CBS, NBC, and UPN are broadcasting in

1080i. Mostly, the DTV broadcasts are simply the same

non-HDTV programming which is on the normal VHF channel.

On occasion, there is true 16:9 HDTV... just as is the case

in most other major cities.


In any case, 1080i on the Sampo is really spectacular. No

complaints. When viewing HBOHD HDTV (e.g. Sopranos) one can

only say "this is what it's supposed to look like". And

the above-mentioned local stations broadcasting off-air in

16:9 and 4:3 1080i are similarly spectacularly clear and

bright and sharp and crisp and colorful.



Which brings me to the remaining stations here in Dallas,

namely FOX and WB... both of whom are broadcasting in 480p.

And I have to say that the picture is truly crummy... not

just by comparison to 1080i, but on an absolute basis.


I don't have a progressive DVD player to compare its 480p

output (Sony 9000ES shipped yesterday, but not received

yet) and I've not seen any other 480p to compare against.


So my question is... could I have a problem with the DST50

putting out 480p? Could the problem be with the Sampo

displaying 480p? Or is 480p inherently this poor?


Even using the AV1/AV2 inputs (S-VHS and RCA, from the

Dish 5000 through VCRs) the Sampo is spectacular. And in

1080i YPbPr it's spectacular. So it seems unlikely that

480p through YPbPr would be problematic, but I won't know

for sure until the DVD player arrives and I can test a

second 480p source for comparison.


It seems more likely to be a problem with the DST50... or

both FOX and WB here in Dallas... or 480p off-air is just

inherently poor (and I mean VERY poor). Not sharp and

crisp, not bright colors, not good contrast... very poor.


It lacks the ring of truth that both FOX and WB could have

quality/transmission problems. It seems more likely to

be a problem at my end, most likely the DST50 (unless it's

the Sampo that has the 480p problem).


FOX also broadcasts some 16:9, such as "Ally McBeal". But

it's still 480p, and it still is pretty washed out and

crummy and not sharp and not clear and not colorful... and

it's nothing like 16:9 at 1080i. I realize there's no

comparison between 480p and 1080i, but surely 480p has to

be better than this.



Any comments? Any suggestions as to how I might diagnose

this problem?


Thanks in advance.
 

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I had a DST50 and I think there was a switch for 480p output on the back, have you tried that? My memory is a little hazy but check the back of the unit. Best, Marvin
 

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The problem is the source, not your equipment. 480p can look great. Fox and WB are just upconverting 480i programs to 480p, and most of the time, not doing a great job of it either. In my system, 480p from a DVD still looks much better than anything FOX or WB has on the air. The CBS and PBS 1080i shows look the bets IMHO.


Chris
 

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I also have a Sampo 16:9.


480p can look very good. But the best is when you convert DVDs to 1920x1080i using a Radeon-equipped HTPC and plug that into your Sampo using RGB.


The result is near-HD quality from a DVD source! Still, it does not equal 1080i CBS or PBS broadcast, but it gets very close.


MMAfia
 

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I have noticed that the upconverted network feeds in the Detroit area look aweful compared to the analog composite satellite feeds (when available) when sent through my HDD200 or directly into my VT540's composite port. Though the VT540 route has the advantage that it is used full panel 1024x768 vs. double letterboxed 768x576 for the HDD200 or local feed (via the Unity Motion). Surprisingly, the HDD200 is not highly rated in its conversion abilities.


What I have suspected for some time (but having no proof) is that the upconversion at the locals is being done with a lower resolution source than that which my HDD200 uses. When comparing the analog locals to the same analog satellite feed (even on an NTSC set), say for football, it has always been evident to me that the local signals are lower resolution (even after RF encoding of the satellite feed). I remember reading that the locals broadcasts are in the 380 lines range whereas the satellite feed is 480. I don't know why they would downgrade the signal prior to local broadcast, but that's my understanding (maybe cost of local insert equipment?). I suppose that the local commercials, et. al. are inserted into the downgraded signal which would be the reason they would pump the downgraded signal into the DTV converter.


Anyway, that would explain why I get a much better picture when using my HDD200 rather than relying upon the local affiliate's upconvertion using a lesser source. Maybe this is what other folks are seeing? I just wish that the analog satellite feeds were available more often. Alas, the age of encryption beckons.



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KDFW broadcasts in 720p--even though the programming is 480i/480p--and with your Sampo you should be able to set the TU-DST50 to output in native format and avoid the extra downconversion step. On my Sony 34HD1 the Fox 16X9 programs, viewed as 480p, look good and appear just slightly softer than most of CBS's 1080i shows, but I agree that the Sopranos this spring looked wonderful and justified our HDTV purchases. The problem I have with the Fox stuff is lip sync and this is often noticeable either with my Sony's tuner or a Panasonic TU-SDT51/PV-HD1000 combo.

Charles
 

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Discussion Starter · #7 ·
Quote:
Originally posted by cnixon:
KDFW broadcasts in 720p--even though the programming is 480i/480p--and with your Sampo you should be able to set the TU-DST50 to output in native format and avoid the extra downconversion step.


On my Sony 34HD1 the Fox 16X9 programs, viewed as 480p, look good and appear just slightly softer than most of CBS's 1080i shows, but I agree that the Sopranos this spring looked wonderful and justified our HDTV purchases.


The problem I have with the Fox stuff is lip sync and this is often noticeable either with my Sony's tuner or a Panasonic TU-SDT51/PV-HD1000 combo.

Charles
I do have my DST50 set in "all ATSC formats" mode. Are you

sure FOX is broadcasting at 720p? Doesn't look that way.

I talked with the engineer there last week (Mark LaValley)

and I'm sure he said they broadcast at 480p... even 16:9.


My 480p symptom is washed-out color, and a much more

blurred/softer image than at 1080i. I'll better be able

to be sure where the problem is when the progressive DVD

player arrives next week and I can try this source.


And I too noticed the lip-sync symptom. Is that a FOX

problem, or a DST50 problem? I'm getting ready to send

the DST50 to Panasonic for checkup/repair, if the 480p

issue is from the tuner and the lip-sync story is also in

the tuner.



On another note, I can't get CBS at all. It's just my

physical location. The signal strength meter shows channel

19 as the absolute weakest of any here in Dallas, and it's

obviously below the tuning threshhold of the DST50.


CBS has said they're on a "standby tower" with about 30%

power, until October when they do their real install. I'm

hoping they move into the "green" at that time, because I'd

love to pick up their nightly shows. ABC, NBC, and UPN

come in great (all at 1080i). I can't get PBS at all.


I tried a Terk TV55 today, temporarily replacing the GE Max

I had been using (I live in an apartment, and am severely

limited as to what I can get away with). It turns out to

have been a considerable degradation from the GE Max. So

back in the box it went, and back went the GE Max on the

roof.


In reinstalling the GE Max, we must have not aimed it quite

the same as before, since I now get ABC strong and clear

but CBS (which I had been receiving fine during the day)

is now gone (input signal found, but channel not available).

Previously, ABC was not as strong and dependable as it

is now, but at least I could get CBS during the day without

too much breakup. At night, CBS disappeared.


I guess I'll just have to wait until October for CBS, and

even then I've simply got to keep my fingers crossed.
 

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DSperber,

I just checked and KDFW is now broadcasting 480p which will display on my Sony with the TU-DST51 set for native output, but I'm pretty certain that last fall they were at 720p because I could not get a viewable picture with native output. CBS's CSI is looking very good now on the TU-DST51 and except for some pixillation problems a couple a months ago during the college basketball playoffs, KTVT has been problem free this season.

Charles
 

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Quote:
Originally posted by teague:
The problem is the source, not your equipment. 480p can look great. Fox and WB are just upconverting 480i programs to 480p, and most of the time, not doing a great job of it either. In my system, 480p from a DVD still looks much better than anything FOX or WB has on the air. The CBS and PBS 1080i shows look the bets IMHO.


Chris
Fox does not "upconvert" to 480p. The film shows that air in this format are delivered on either DCT or Digital Betacam tape that has been processed to have continuous cadence (in other words, continuous 3:2 pulldown). This pulldown is detected when the tape is used for broadcast and the additional fields are removed, yielding the original 24 film frames per second. This is sent out over Fox's digital feed. There is no upconversion involved.


One can't compare DVD's to broadcast television. When DVD's are made, the orignal source material is MPEG2 compressed using manually optimized, scene by scene compression. In other words, an operator (called a "compressionist" these days) goes through each scene and determines just how much compression the scene can undergo without compromising the material and causing unwanted artifacts. Broadcast television is compressed in real time as it airs. This is inherently not as effective as programmed compression. In addition, DVD's are usually theatrical films, which have far more attention lavished on lighting and far more equipment and time allowed for this purpose than television programs.


Mike Most

Visual Effects Supervisor

Los Angeles

 

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Here in the S.F. bay area all the stations that send out a continuos HD signal have pictures that are better than DVD for most programs. Most of the programs on the SD stations are about DVD quality. The lack of noise and interference is extremely evident. If the stations are just upconverting the NTSC instead of the studio quality video it will make a difference.



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I also have the Panasonic DST-50 and you are absolutely correct. I have seen exactly what you have noted on my direct view set as well.


FOX's format is actually 480p for their 16:9 programming, such as X-Files. Here in Boston, FOX was transmitting in 720p, in essence upconverting 480p, up until last week when they began 480p.


The best way to describe the FOX 480p in blurry which is bad since the up-converted 720p looked as good as it gets without actually being HD. 480i actually looks better and isn't that sad? What's even sadder is the 720p FOX transmissions riveled that of my better DVD's on my progressive scan DVD player.


Since you have no 720p transmissions where you are you can't do a comparison. However, I have. The 480p that FOX now transmits looks exactly the same as when the DST-50 downconverts a 720p transmission to 480p...blurry.


I know it's not my monitor since many DVD's look great on my progressive scan DVD player which is 480p. I know that down-converting 720p to 480p looks terrible on the DST-50 and I know the DST-50 isn't doing the down-converting on my local FOX station. So, the question is, what's up with 480p transmissions looking so horrible?


Obviously, there is something wrong. It looks like there is some sort of down-conversion going on, at some level. Keep in mind the 720p FOX transmissions looked great and the 480p transmissions of the exact same material looks really poor.


Anyone care to guess as to why?


By the way, it's interesting to note that there are now two documented cases of FOX affiliates switching from 720p transmissions to 480p. Anyone know what's up with that?
 
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