Picture degradation with TiVo

[JGiVo]

Hi,
Why does my digital cable picture suffer so much degradation when going through my TiVo box? When I view the signal directly (cable directly into TV) it's fine. When passing through TiVo, very grainy. TV is a Sylvania 20" LCD (not HD). I love TiVo but not satisfied with picture quality. Second question, can the picture be improved?

[ZikZak]

Because the standalone tivo uses MPEG comression, which is lossy. The first thing to try is to turn the "sharpness" control on your TV all the way down, to where it should be--- usually at the very bottom. This usually solves the problem. You can also ask the cable company to boost your signal, or get a cable amplifier from Radio Shack. That too can help.

[T*i*V*o]

Had the same problem setting up the TiVo.

My suggestion and it worked...we also have Wireless, Direct Cable....

When we pushed the TiVo unit back into the space it would get fuzzy, but if we pulled in out a little until the clear picture returned. I am thinking the wires were getting a little bent and therefore not a good connection.

It worked for us.

[gtrogue]

Are you talking about live TV or a recorded show?
When viewing live TV I don't really notice a difference in quality.

Recorded shows suffer to a greater or lesser degree depending on the recording quality you select.

With cable and satellite there is always the problem of garbage in=garbage out. A marginal signal that looks fine without the Tivo has all it's flaws magnified once mpeg compression comes into play.

If the degradation is really bad for live TV (best quality) there may be a hardware issue somewhere.

[wscannell]

When watching live TV, the TiVo buffer is recording a Best quality. Unless the live program you are watching is also being recorded. In that case, the live tv is being shown at the quality it is being recorded at.

[JGiVo]

Are you talking about live TV or a recorded show?
When viewing live TV I don't really notice a difference in quality.
Live TV.

[ZikZak]

Live TV.

It makes no difference. Tivo's "Live TV" is actually a recording.

[gregpg]

Because the standalone tivo uses MPEG comression, which is lossy. The first thing to try is to turn the "sharpness" control on your TV all the way down, to where it should be--- usually at the very bottom. This usually solves the problem. You can also ask the cable company to boost your signal, or get a cable amplifier from Radio Shack. That too can help.

That kind of puts the cart before the horse :rolleyes:. The OP should first make sure his RF coax cables are RG6 rather than RG59 to minimize signal loss from the wall to the cable box and to the TiVo. If the picture is still unsatisfactory, then he needs to call the cable company about signal quality. If the picture still bites, he needs to get a cable amplifier. As the last resort, he could reduce the sharpness and picture settings on his TV, since the biggest reason most people have for getting a modern TV is likely to get a sharper, brighter picture.

[ZikZak]

As the last resort, he could reduce the sharpness and picture settings on his TV, since the biggest reason most people have for getting a modern TV is likely to get a sharper, brighter picture.

Are you seriously suggesting that he should properly adjust his set only as a last resort?

Any "modern TV" set manufactured after 1990 will come with a comb filter, on which the sharpness control (if turned to anything but zero) does absolutely nothing except add noise to the picture---- exactly the kind of high frequency noise that would incorrectly enhance the appearance of MPEG pixellation.

[gregbert]

Hi,
Why does my digital cable picture suffer so much degradation when going through my TiVo box? When I view the signal directly (cable directly into TV) it's fine. When passing through TiVo, very grainy. TV is a Sylvania 20" LCD (not HD). I love TiVo but not satisfied with picture quality. Second question, can the picture be improved?

Here's one potential solution:

If you have a Dual Tuner like me, The TIVO actually uses the analog signal rather than the digital signal for all channels below 100.
All the <100 channels are not broadcast in digital, but because of the RF signal degradation, the digital cable box also has the quality that it cleans up even non-digital signals. If you enable your digital signals in your channel list, you wil then have two choices for every channel below 100 - 1 digital and 1 analog. Still havent figured out how to get it to record my shows on the digital yet though.

[gregpg]

Are you seriously suggesting that he should properly adjust his set only as a last resort?

Any "modern TV" set manufactured after 1990 will come with a comb filter, on which the sharpness control (if turned to anything but zero) does absolutely nothing except add noise to the picture---- exactly the kind of high frequency noise that would incorrectly enhance the appearance of MPEG pixellation.

Yes I am suggesting that. I have one analog TV manufactured in 1992 and a HDTV built in 1995. Both give a good picture from the TiVo RCA input (for local channels) and a terrific picture from DVD input (which is also MPEG derived for anyone who doesn't know), and that's with the sharpness and brightness controls set to medium. On the analog set, reducing the sharpness has the effect of blurring all the details out of the picture, and on the HD set, reducing brightness seems to offer a better correction for snow than reducing the sharpness. I fix pixellation the same way I fix ghosting, by turning the antenna to effectively boost the signal. Both TVs display a better image when connected directly to the antenna than when connected through the TiVo. The difference seems due more to a lack of detail than pixellation and is probably a result of stand-alone S2 tuners being inferior to most TV tuners.

Regarding cabling, superior insulation provides superior resistance to the kind of noise that causes ghosts, snow, and MPEG pixellation. This is so important for modern TVs that you can't find aftermarket RG59 RF coax cables at most stores, only RG6. Nonetheless, many devices come with RG59 cables included in the box because RG59 is marginally cheaper than RG6.

[ZikZak]

gregpg,

Sure, better cables will improve the picture. Sounds good to me.

But your TV is whoppingly out of calibration. I suggest a $15 calibration DVD to compliment your $2500 CRT.

[gtrogue]

But your TV is whoppingly out of calibration. I suggest a $15 calibration DVD to compliment your $2500 CRT.
I agree. If your sharpeness setting is very far above zero then your not getting the best picture.
The sharpness setting, like all the settings on a TV out of the box, are meant to provide a bright, eye catching picture in a bright store without optimum viewing conditions. They are not the best picture quality settings.