I want to get a 42" lcd tv.. and surround sound. i watch quite a few movies and lots of satellite television(Direct TV). What do i need to look for to get a nice looking picture?
and as for 720p and 1080p go.. what is the diff? And do i need to get HD channels for my reciever or are they already on there?
The specifications 720p, 1080i, and 1080p are identifying the number of lines that are used to plot the picture on the TV and are what defines the TV as being High Definition. When the picture is plotted it is done using a series of horizontal lines that progress from the bottom of the screen to the top one frame at a time. So for 720p it uses 720 lines, 1080i or 1080p uses 1080 lines. This is done in one of 2 ways with progressive or interlaced lines. The "p" in the specification indicates that its progressive and the "i" in the specification indicates interlaced. Progressive indicates that the lines are plotted one at a time in sequence on each pass or frame. In other words it plots line 1, then 2, then 3 and so on. Interlaced indicates that the lines are plotted even numbers on one pass then odd numbers on the next. Progressive is obviously better because it plots the whole frame on one pass while interlaced requires 2 passes to plot one frame.
Standard TV's (before high definition) were 480i meaning 480 lines were used and were plotted even numbers on one pass and odd on the second pass requiring two passes to plot one frame.
While the differences in the number of lines used should indicate a better picture when more lines are used this is not always the case. In fact this is a commonly misheld belief. There are 720p display devices out there that have a better picture than some 1080i or 1080p display devices. The best way to tell what you prefer is to go to a store and view the picture then decide for yourself which is better but do not be lead to believe that just because the TV uses more lines to plot that its a better TV because as I think you will find this is not always the case. Utimately the best 1080p display device available would be better than the best 720p display available but the fact remains that some 720p display devices are better than some 1080i or 1080p display devices. This not to say that you would go any lower than 720p but you cannot anyway because all high def TV's are at least 720p.
Currently all sattelite and cable sources broadcast no higher than 1080i. Blu-ray players are 1080p.
You do have to have a high definition tuner to display high definition content.