1. The video processing circuitry in an HDTV upscales the image, which can improve the good aspects of the image. However, at the same time, the video processing also will magnify the defective parts of the image, such as interference and video noise that is not as noticeable on a lower resolution analog set. In this case, the quality of the video processing in the TV can have either a positive or negative effect on the degree of correction for poor analog signals.
2. If you have upgraded from a 27-inch (as an example) analog television, to an large screen Plasma (lets say 42-inches) - the lower resolution analog image will degrade somewhat since you are blowing the image up to a larger size. This is especially noticeable on VHS recordings as VHS is such a poor quality source to begin with.
However, in some cases, it may not only be the TV that is a fault. If you receive your television channels over the air, it may be simply a matter of geography as to the quality of your incoming signal, however, you may be able upgrade your antenna.
In addition, if you experience poor analog reception on your HDTV and you subscribe to a cable service, switching to digital or HD cable or having the cable service come out and check your line may also help to improve the matter.
In the final analysis, take care that in 2009 (as it stands now), all broadcast signals are scheduled to go digital and the poor analog broadcast issue should be a thing of the past for television broadcast signals. However, if you are still viewing low resolution analog video sources on your HDTV, such as VHS tape, such sources many still look worse that they might on a more forgiving analog television.
