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I have 2 tv's in mind to buy, one is the Sharp 30" Aquos LCD, LC30HV4U, or the Hitachi 32" plasma, 32HDT20. Does anyone have either one of these and can give me any comments on them? Keep in mind this is going to be a master bedroom tv, so 720p is good enough. I personally like the Sharp better because of the clear picture and price, but if I am still open.

Also, does anyone have a link that would compare plasma tv's to lcd's? just some general info.



Thanks
 

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I don't think anyone here has ever thought to compare LCDs to plasmas. That's a great idea!


Just kidding.


If you like the Sharp better, buy the Sharp. It's a very nice TV. Seriously.


Mark
 

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I like both of those two models myself. They are a great size for the room I have that needs a TV. I would go with the sharp though since it is an LCD....they never burn in. :)
 

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Though its a bit outdated already (from 4th qtr last year), the one comparison most people point to is found at:

http://www.phpcom.com/Pages/plasma4.html


This includes the forerunner to the Sharp you are looking at.
 

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quadad,


That Putman's test is kind of ridiculous.

According to the results, some displays resolve full 720p out to 37.5 MHz of bandwidth, while fail in 1080i out to 37.5 MHz. But, some fail in 720p out to 37.5 MHz, while resolve full 1080i out to 37.5 MHz.


I mean.... 1080i, and 720p can be considered the same bandwidth. Why on earth some display can resolve 37.5 MHz bandwidth of 720p, but not 37.5 MHz of 1080i, or vice versa ?? After all, bandwidth-wise, 720p, and 1080i are the same.

http://www.phpcom.com/Images/ptv3.gif
 

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My quick comments:

1) Good luck finding other LCD vs plasma comparisons, despite its limitations, this is the only somewhat comprehensive one I have seen in over six months of looking. Hopefully there are more out there.\\

2) Is that true about the bandwidth ? Need input from the video pros out there. My VERY limited understanding was that 1080i meant it only puts out 540 lines every display update which would take less bandwidth than 780 every display in progressive mode. (To be corrected and further detailed by others.)
 

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Quote:
My VERY limited understanding was that 1080i meant it only puts out 540 lines every display update which would take less bandwidth than 780 every display in progressive mode. (To be corrected and further detailed by others.)
You don't need video pros for simple bandwidth calculations. :)

#1080i HD has 1080 scan lines containing picture information (and 45 scan lines for retrace and synchroniziing for a total of 1125 scan lines). Horizontally there are 1920 visible pixels occupying the first 87.3% of the scan line and we must pretend that there are 140 similarly sized sync. pulses with 140 gaps in between, filling the rest of the scan line. (The total pixel count is 2200 per scan line.)


The scan rate is 30 (29.97) full video frames per second.


Multiply 1125 x 2200 x 30 seconds and we get about 74 million pixels per second. Since one cycle consists of one black and one white pixel, the bandwidth needed to display the smallest picture details is 37 MHz.

# 720p HD. Coincidentally, 720p also requires 37 MHz.. 720p has 1280 visible pixels and room for 1650 total pixels per scan line. It has 720 visible and 750 total scan lines repainted approx. 60 times a second. 750 x 1650 x 60 is about 74 million black/white pixel pairs or about 37 million cycles per second.


Now..1080i, and 720p, they both have the same bandwidth. How can a display can fully resolve one while failing the other ? I maybe missing something in this regard, but I think the Putman's review/benchmark is misleading.
 
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