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Size vs. Quality? Sharp LC-80LE844U vs Panasonic TC-P65VT50 - Page 3

post #61 of 69
Well they are pretty "sharp" biggrin.gifbiggrin.gifbiggrin.gif but yeah the basic sharps aren't really going for top of the line picture quality and features, they excel at offering a big screen that does well in a bright or moderately bright environment.
They also offer some decent uniformity in there larger sets with full array that is hard to find in the price range. They aren't a high end screen, if you want a high end lcd that is competitive with the vt50 you have to pay alot more for it.
post #62 of 69
Quote:
Originally Posted by chunon View Post

Flicker and likely buzzing doesnt sound like plasma will work for you

Well, I guess we will just have to see, won't we? I did own two Panny plasmas from 04 to 08 and was never bothered by flicker or buzzing. Switched to LCD and now looking to switch back. If the flicker and buzzing bother me, either the new plasmas are much worse about it, or LCD has spoiled me, or I'm becoming WAY too sensitive as they years go by! Good thing I chose a place with excellent return policy.
post #63 of 69
Quote:
Originally Posted by Flavius View Post

Well, if you don't see it, it must not exist in your universe. Congratulations, you are very lucky. But for those of us who DO see it, it is real.
If the Sammy plasma I'm getting tomorrow flickers like the plasmas in the stores, it's getting returned. I know what judder is, it was not judder, it was strobe light full screen extremely rapid flickering as you'd see on a 60HZ CRT computer monitor.
Google plasma and flicker, I am not the only one who sees this.

You're clearly seeing *something* but it's not flicker. I'd love to figure out what it is. A plasma doesn't really do anything at 60 Hz. Maybe you're seeing the room lights flicker.
post #64 of 69
Quote:
Originally Posted by jonnythan View Post

Maybe you're seeing the room lights flicker.

Ok, now you're just trolling me.
post #65 of 69
I'm sure he's seeing a 60hz flicker. When I walk through a store and a plasma is showing bright content it is easy to see this flicker out of the corner of my eye. In other words the screen is turning on and off at 60fps. In the 600 times per second only the first few cycles are bright enough to see then they get darker and the perception is a turned off screen. On the older plasmas the the brighter cycling is near the end of the timeframe. But they still flicker lights on or off.

At home this is less of a problem mainly because the tv is better calibrated and not as bright. I really never notice any issues from this and it's nothing like a 60hz pc crt which were nasty, I always go for the highest refresh rate adjustment first thing when setting one up.
post #66 of 69
Quote:
Originally Posted by whipit View Post

I'm sure he's seeing a 60hz flicker. When I walk through a store and a plasma is showing bright content it is easy to see this flicker out of the corner of my eye. In other words the screen is turning on and off at 60fps. In the 600 times per second only the first few cycles are bright enough to see then they get darker and the perception is a turned off screen. On the older plasmas the the brighter cycling is near the end of the timeframe. But they still flicker lights on or off.
At home this is less of a problem mainly because the tv is better calibrated and not as bright. I really never notice any issues from this and it's nothing like a 60hz pc crt which were nasty, I always go for the highest refresh rate adjustment first thing when setting one up.

Ok, so you're saying older plasmas like a 2007 era Panasonic may have LESS visible flicker than a modern plasma? Might explain why I didn't see it on my old plasmas. Yipes.
post #67 of 69
The 60Hz flicker described is a phenomenon called "optical hetrodyne" and it happens when two sources of pulsing light are close to one another in frequency but not exactly matched, and one sees a flicker equal to the difference in the two frequencies. In this case the two frequencies are the 60Hz screen refresh and the 60Hz from flourescent lighting. It is exactly the same phenomenon as one used to see on old direct-view CRT computer monitors with screen refresh near 60Hz. If the two frequencies were well matched, you saw a rolling black bar representing the time when they were out of phase, and a bright bar midway in between when the intensity of both was maximum. If the two frequencies differed by 1Hz or more, you see the entire screen flicker.

Older direct-view CRT TV's avoided flicker by locking the vertical screen refresh to the powerline frequency. This technique is not easily applied to plasma displays. However if you are troubled by flicker you can eliminate it or reduce it greatly by replacing all the room lighting with old-fashioned, inefficient incandescent bulbs. These types of bulbs do not flicker much, compared to the compact flourescent or conventional flourescents used in homes, or the high-pressure mercury vapor bulbs used in big box stores or Best Buy.

Now you know the "other reason" that plasma displays are demo'd in relative darkness in the back of the store. The main one is to suppress reflections, but flicker reduction also happens.

If troubled by flicker, diagnosis of this problem is easy. Turn off all the room lighting one by one, and replace the offending bulbs.
post #68 of 69
An erudite answer!

Thanks, Gary.

smile.gif
post #69 of 69
Quote:
Originally Posted by Gary McCoy View Post

The 60Hz flicker described is a phenomenon called "optical hetrodyne" and it happens when two sources of pulsing light are close to one another in frequency but not exactly matched, and one sees a flicker equal to the difference in the two frequencies. In this case the two frequencies are the 60Hz screen refresh and the 60Hz from flourescent lighting. It is exactly the same phenomenon as one used to see on old direct-view CRT computer monitors with screen refresh near 60Hz. If the two frequencies were well matched, you saw a rolling black bar representing the time when they were out of phase, and a bright bar midway in between when the intensity of both was maximum. If the two frequencies differed by 1Hz or more, you see the entire screen flicker.
Older direct-view CRT TV's avoided flicker by locking the vertical screen refresh to the powerline frequency. This technique is not easily applied to plasma displays. However if you are troubled by flicker you can eliminate it or reduce it greatly by replacing all the room lighting with old-fashioned, inefficient incandescent bulbs. These types of bulbs do not flicker much, compared to the compact flourescent or conventional flourescents used in homes, or the high-pressure mercury vapor bulbs used in big box stores or Best Buy.
Now you know the "other reason" that plasma displays are demo'd in relative darkness in the back of the store. The main one is to suppress reflections, but flicker reduction also happens.
If troubled by flicker, diagnosis of this problem is easy. Turn off all the room lighting one by one, and replace the offending bulbs.

I'm sure you have a point, but I think there are other causes of perceived plasma flicker. The ones I noticed flickering where in the Magnolia section of BestBuy, which I do not think has fluorescent lighting, but rather dimmed incandescent. Guess we'll see what happens at my house next week when I get my plasma, as there is no trace of flourescent light anywhere in my house. (because it flickers!)
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