# image quality



## guyravad (Sep 10, 2002)

Greetings everyone. I am new to this forum and new to satellite service. Over the last year I have had digital cable thru Time Warner. Last week I switched to DISH and installed two 508 receivers and two 301s. Image quality looks great on my 27in and smaller TVs but worse on my 60 inch Pioneer Elite PR200 (analog TV). A/B comparison of Cable vs Satellite (508s only) using coaxial or s-video confirms the superiority of cable in my case. There appears to be more resolution in the image and it is less prone to smoothing out facial wrinkles and hair stubble. There is also more depth to the image a feature that the PR200 is great at bringing out. When people are far off in the image their faces blur out but not so on cable. The satellite picture quality is good and sharp-it is not an issue of poor quality, it is just noticable inferior to my cable TV which was very good. 

Even without the A/B comparison I find the picture quality lacking and notice the differences, mainly digital artefacts. 

So my question is what's going on? Is the quality of the picture different btw digital cable and PVR 508? Is the quality of the satellite picture different btw the 301 and 508 (a comparison I have not yet performed)? My signal strength is over 100 from both satellites. Also the image from the 508s tends to exaggerate the reds. Is this a charateristic of the receiver? Does anyone know the output resolution of the 508/301s vs the digital cable boxes? Or is it the compression that is excessive? 

I would appreciate any comments. Curently I am in it for a year but if there is no way to improve the image quality I'll probably switch back to cable since the analog and digital both look better on my big screen TV. 

Thanks, 

Guy


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## MarkA (Mar 23, 2002)

DISH blurs the picture a lot. DirecTV has a sharper image. Digital cable varies depending on where you live, and not all channels are digital - which may be what you see.


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## P Smith (Jul 25, 2002)

According discussion at one Yahoo group - "the native 544 x 480 r#$%d from the drive".


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## guyravad (Sep 10, 2002)

Thanks. So Dish is blurry compared to Direct TV? I should have gone with UTV or TIVO! And yes my cable channels 0-99 are analog, but appear clearer than DISH images-even on the 60 inch TV.

And, P Smith, thanks for your reply but I do not know what "the native 544 x 480 r#$%d from the drive" means. Could you please elaborate?

Thanks, Guy


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## Scottyo (Sep 10, 2002)

First off I wish to strongly disagree with Zac, Dish Network does not blur it picture. Nor is the picture quality of DirecTv sharper. I have been into consumer electronic for years. I went from the big C band dish to Dish Network. Before I purchased the smaller dish I went to friend, family and satellite dealers to compare the difference between the the three (Dish Network, 
DirecTV and Primestar). I found that I have a hard time reading the online graphics and guide on DirecTV.

I do not have either the 301 or the 508, but I do have the 501. The only difference between a 501 and a 508 is the size of the hard drives. The picture quality that I receive on my 32 Sony from any of my Dish receivers is excellent. Also I haven't notice any problem with colors being exaggerate.

I have read about several problems with DirecTV's Ultimate system. I haven't heard anything bad about Tivo, but both they and DirecTV charge a monthly fee to use the record and other special feature. 

As for comparing Dish to cable I have never had cable, so I haven't done any comparison between the two.

You may want to contact a Dish Network Technican to see if they have any suggestion on improving your picture quality.


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## guyravad (Sep 10, 2002)

Thanks. I am glad to hear that there isn't a difference btw direct TV and DISH.

Reading many old posts I see that there is a great variability in PQ. Some people love it and some say it is too soft. Perhaps it has alot to do with the TV size and capabilities. I am sure I would not have a problem with the PQ on a 32 inch TV. It is my 60 inch that is the problem. To be fair, I must admit that over a year ago when I first activated my digital cable I was disappointed with half of the digital channels. They were way too soft and had lots of freezing, pixelization, etc. But the "high end, premium channels looked great and I never once thought the PQ was bad. So this week when I got DISH and thought things looks fuzzy (big screen only) I made several comparison tests. I A/B compared the two 508s in case one receiver was defective. There was no difference. Then I hooked up my pioneer cable box and A/B compared the same shows and saw the difference. It is very dramatic. I even handicapped cable by running it thru the coax and the DISH through SVideo. Then I compared the worst quality digital cable channels to the same DISH channels and cable still looked slightly better. I brought in a friend and did blinded comparisons. Same results.

It is obvious from reading several old threads that everyone's cable service is of variable quality. Mine happens to be very good and I can tell the difference. In general I believe that most users will be better off with DISH than cable, particularly for screen sizes less than 42 inches, since all of the channels are digital.

Hopefully, DISH increases the bit rate because if they do not, in a year I will drop them like a hot potato. By then digital cable in my area will also offer PVRs which is the big benefit of satellite.

Guy


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## Mike123abc (Jul 19, 2002)

Good thing you just got Dish, a couple months ago you would have been really, really disappointed. At least they are making progress with E7 and soon with E8. They way exceeded their carrying capacity Jan 1 when must carry hit them hard.

I almost discontinued Dish when my first year was up in April, but they had started to make good progress. I decided to give them another year to get their act together.

Right now most stations are still under cable quality. Maybe by end of the year with E8 working full time they will have PQ up to pass cable again.


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## DarrellP (Apr 24, 2002)

A good, clean analog signal will beat anything Dish has to offer (except HD).


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## MarkA (Mar 23, 2002)

DISH doesn't "blur" the picture, no - I oversimplified that. They use a lower horizontal encoding resolution, along with half-resolution Pr and Pb components, along with some noise-reduction pre-filtering - all of which reduce overall image detail. Same thing However, because DirecTV doesn't do this - you have many more noticeable MPEG2 artifacts. Personally I prefer DirecTV's picture. It's very DIFFERENT (not technically BETTER since they both use the same compression and allow about the same average bandwidth per channel).


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## guyravad (Sep 10, 2002)

In what way does direct TVs pic look different?


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## zimm0who0net (Aug 27, 2002)

I think Zac answered that. Dish broadcasts 480 x 480 images and scales up in the set top. DirecTV uses full 720 x 480 images, but compresses them more. Result is a similar bit rate (space occupied on the satellite). Picture results will be sharper, higher resolution images in DirecTV, but with more MPEG induced artifacts during fast motion sequences. MPEG artifacts are where you start seeing portions of the image temporarily turn into 16 x 16 pixel squares when there's not enough bandwidth to transmit that particular sequence.


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## P Smith (Jul 25, 2002)

Actually, by group who have knowledge how convert records from PVR50x to DVD, the resolution is 544 x 480 . So nothing to "scales up" . Just fit into regular TV resolution ...


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## scooper (Apr 22, 2002)

Picture quality is a highly subjective thing. DBS tends to look best on 27" NTSC and smaller TV's.

That being said, there ARE things owners of larger screen TV's can do to improve their picture.

#1 - Turn DOWN the sharpness and adjust your TV out of "Torch Mode". This is only a precursor to -

#2 - Get your TV picture calibrated, by an ISF professional is the best, but you can do quite a bit with the Avia and Video Essentials DVD's.

There have been debates over what input you HDTV-Ready monitor owners should use. Since I don't own such a set, my opinion here is not as valid, but it would seem to me that your best picture on Standard channels should be the S-Video / composite NTSC, and let your TV set's internal doubler do the work - it's probably a higher quality unit than the comparable on the satellite IRDs. This may vary for each viewer/ equipment.


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## Kagato (Jul 1, 2002)

The issue is two parts. 1) Since DBS is VBR quality will vary channel to channel. Locals usually looking the worst. HBO and other premiums the best. 

2) Not all big TVs are the same. Just because it's HD ready doesn't mean it will display an interlaced S-video based signal well. I have a HD LCD video projector and a buddy with a HD RPTV (About a 3K set, middle of the road). Both of us have Dish and mine looks much better. It's all in the video scaler. Many HDTV's being sold in the retail channel don't have much in terms of built in video processing. They all say they have a "line doubler" or "video scaler" but I've yet to see one that does a good job. Which is why external processes are still very popular. For many people it's the best $600-$1000 they will ever spend on their HDTV.

And of course as scooper mentioned, the contrast on your TV from the factory is obscene. 

I myself have found with my projector that the component video output looks the best. But s-vid is still very good. And the 721 looks much better than the STB Tivo I had on s-vid.


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## guyravad (Sep 10, 2002)

Yes in fact turning down the sharpness does help a little. I found that out by experimentation.

It's too bad that DBS looks worse than cable for me on my 60" pioneer elite analog TV. I'm cancelling satellite the second my contract is up. By then cable will have a PVR option in my town. My HBO with digital cable appeared to be DVD quality.


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## TomCat (Aug 31, 2002)

> _Originally posted by Kagato _
> *...Since DBS is VBR quality will vary channel to channel. Locals usually looking the worst. HBO and other premiums the best...the 721 looks much better than the STB Tivo I had on s-vid. *


VBR is a separate issue. If done correctly VBR is as transparent as constant bit rate, yet more efficient. Current technology limits the amount of VBR that can be decoded by cheap STB's quickly enough to not having noticeable lag time to just a few percent, anyway. The reasons that quality varys from channel to channel are due to a combination of things, but VBR isn't really significant enough to be one of them.

First is the quality of the original signal, and most DBS signals are turned around from fiber, or TVRO dishes, so the original quality covers quite a spectrum. Some locals are even picked up OTA before being transported to the uplink site (which should be a crime). PPV's are usually originated from a server which got it's copy from a digital tape or over a WAN connection, which helps them look better than most garden-variety cable networks.

Second, the amount of and quality of the NR and other pre-processing is more art than science, although the newer the equipment, the better the end result. The must-carry crunch meant intant re-commissioning of a lot of antiquated equipment, which is a contributor to why the locals look so terrible.

Third, arbitrary decisions made in stat-mux configuration put a bit rate ceiling on every channel depending upon how "important" it is (PPV's having more importance, third-rate CNN wannabe's having the least). Should a channel's content create a spike in how many bits are needed to properly encode it and not be able to do that due to running into that arbitrary ceiling, it gets bit-starved and pixellates at decode.

Interestingly, the amount of human maintenance skill used at every stage from production all the way to your display device probably has more to do with varying quality than does the technology itself.


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## Mike123abc (Jul 19, 2002)

TomCat is right on the poor way VBR is done on E/D right now. Each channel essentially has a constant bit rate. Just the bit rate allocated per channel varies on the same transponder.

Well it all comes down to bits. Right now D/E* are trapped by old settop boxes. A truly modern box would be capable of:

1. 8PSK (like dish now used for HDTV) with 16QAM capablility if they get sats powerful enough to do it. 8PSK gives 30-50% more bits per transponder. 16QAM does not look pratical at this time because the transponders on the satellite would have to be 4X as powerful as they are now. But, they could put up a sat that does 8 instead of trying to drive 32 transponders at once. Having the flexibility for the future would help.

2. True VBR. If each channel on the transponder could have its bit rate vary from say near 0 to 10mbit/sec peak as needed, near DVD quality would result. This is even better with 8PSK because with more channels it is more likely that some will be using very few bits when others need it. Putting 10 channels of sports PPV would not be the best, but mixing sports, news, etc would give excellent opportunity to move bits around (even news shows show action and sports every now and then).


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