[mythtv-users] [OT] LCD TV or LCD Monitor for Front-end

Michael T. Dean mtdean at thirdcontact.com
Tue Jan 31 20:45:31 UTC 2012

On 01/31/2012 02:45 PM, John Welch wrote:
> In my bedroom I
> currently have a Samsung 26" 720p LCD TV connected as a frontend.  In 
> addition
> to the frontend PC, I also have the TV connected to a cable box and a 
> blu-ray
> player.
> So, now I've started looking around for a possible replacement.  My 
> question is
> do I get another LCD TV, or are the LCD monitors that are out there 
> now as good
> or better for what I need?  I really want to get something capable of 
> FullHD
> (1080p), especially since I now have the blu-ray player.  I'm strongly
> considering something with an LED backlight, but I guess that isn't a
> necessity if I find something that fits my needs without it.  With 
> these specs
> in mind I've seen several Acer, Asus, Viewsonic, etc. 27" LED-LCD 1080p
> monitors that consistently get good reviews / ratings in the $250-$350 
> range,
> which fits my budget.  For LCD TV's I am only seeing a couple of Vizio 26"
> models with similar specs as the monitors in this same price range.

Without having looked into monitors for use in video playback (and, 
therefore, without knowing what's available), I will mention that LCD 
(including LCD with LED backlight, which--regardless of what the 
TV/monitor manufacturers claim--are not LED TVs/monitors***) is a 
terrible technology for use with video. Because an LCD pixel is 
generally full brightness all the time--rather than starting at full 
brightness and dimming over time until the next scan, as was the case 
with CRT-based monitors/TVs--there can be quite distinct pixel->pixel 
transitions that look "wrong."

Now, because LCD is a terrible choice for video, the industry decided to 
come up with approaches to compensate for LCD's display characteristics 
to allow them to use LCD for video.  Originally, the first generation of 
TVs to compensate for LCD characteristics would display the pixel at 
full brightness for 1/2 (or some other fraction) of a frame duration and 
then display blackness for 1/2 of the duration (so, for a 60fps video, 
you'd see the pixel at full brightness for 1/120th of a second and at 
black for 1/120th).  However, this reduced the brightness of the display 
significantly, so some manufacturers started to display full brightness 
for 1/2 of a frame, then a dimmed version of the same pixel for 1/2 of a 
frame.  This reduced the brightness, but not as much as using full 
black.  Both of these approaches work very well, and due to persistence 
of vision, look very "natural."  Unfortunately, because there was a 
brightness loss (and because brightness in a store display is what sells 
a /lot/ of LCD screens) some manufacturers got the idea that it would be 
better to invent new pixels--i.e. try to interpolate pixel positions 
between frames--and display those at full brightness (so you got 1/120th 
second of the pixel specified in the video, then 1/120th second of the 
pixel they expected would have existed if the video were 120fps).  Some 
have taken it farther to try to get to 240Hz (inventing 3 pixels for 
every one specified in the video).

Now, regardless of which tech you prefer (and, unfortunately, you don't 
get much choice these days as "bigger numbers = better", so most are 
using the interpolation technique to get higher brightness), you 
probably want to get a display that actually does factor in the LCD's 
characteristics when displaying video.  It's quite possible you won't 
find such workarounds on many/most monitors (as those same ideas would 
be awful for non-video computer displays).

Oh, and I'll also mention--although it's probably not a problem these 
days--that if you do get a monitor for use with video, you'll want to 
make sure it's a 16:9 (= 1920x1080) aspect ratio (rather than 16:10 = 
1920x1200).  Unfortunately for those of us who do work on computers, the 
industry has basically switched production to all 1920x1080 panels, so 
you end up paying quite a bit more to get 1920x1200 (and 1920x1200 is 
great because it allows, basically, 2 portrait pages (even A4 size) side 
by side on the monitor without having to scroll down to see the bottom 
of the page and without wasting a portion of the screen size by scaling 
width to fit height).


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