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Discussion Starter · #1 ·
May be a longshot, but thought I would query the wise folks here to see if anyone has any knowledge / experience with LCD televisions and seizures. A member of my family has a seizure disorder, with seizures that are triggered by light (not only flashing light, but that can be even worse). As a result, she can't really watch TV. I've heard a couple of anecdotes that people with seizures while watching TV fare much better with the new 120hz sets.


I'm getting a new set soon, and my frontrunner is the Samsung LN46A550. But if there is a reasonable shot that 120hz would allow some TV watching for someone with seizures, I'd jump up to the LN46A650. I prefer the matte screen of the 550 to the glossy screen of the 650, and that "Touch of Color" on the 650 looks like butt to me, but if it helps my kid, then I can certainly put up with it.


Any thoughts?


Thanks in advance!


Maxion
 

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Never heard anything about seizures with 120hz sets. LCD do not pulse or flicker like Plasma & CRT sets, so they should be fine with for you.


120hz is just for 5:5 pulldown in movies, they also offer an option of Auto Motion Plus which ups the framerate to 60, so everything will look smoother & not stutter, which might or might not help you.
 

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 lank


it says here avoid anything between 5 and 30 hz but there are other factors you probably know already. Yea i would think 120hz lcd would be a great idea or how about the new 240hz lcds just comming out.


its said turning off motion flow or whatever doesnt affect the frequency so thats good (i still think the special case of pc mode on my computer is 60hz just to let you know)


i think low frame rates / frequencies mess with your mind in a lot of ways..
 

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You probably should consult a physician.
 

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Discussion Starter · #6 ·
Thanks all.


borf -- 240hz sets are not widespread yet, are they? I doubt I'll wait for those to become common.


sharkcohen -- I probably should have mentioned that we talk to her doctors all the time, and have asked about this. Sadly, it does not appear to have been studied and there is little "official" guidance other than "higher seems likely to be better." Really it is trial and error. I was wondering if anyone had dealt with this personally and had found a difference.


FragHD -- I'll check out the a630 -- thanks!


wtfer -- I did not realize that the 120hz did not apply to all viewing. For us newbies, what exactly does it mean that "120hz is just for 5:5 pulldown in movies"?


Thanks again!


Maxion
 

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Quote:
Originally Posted by wtfer /forum/post/15458958


120hz is just for 5:5 pulldown in movies, they also offer an option of Auto Motion Plus which ups the framerate to 60, so everything will look smoother & not stutter, which might or might not help you.

I don't think this is correct. Isn't everything displayed at 120Hz regardless of source? And AMP doesn't have anything to do with 120 Hz.


I could be wrong though.
 

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Let me preface this by saying, yes, I have had seizures in the past produced by certain lighting, esp. in dept. stores, and from video games and fast moving action on TV. I have never taken any medication although I have a history of mild focal seizures.


However, I never even thought about an LCD TV having effects on me as this is the first time I ever bought one....just 2 weeks ago. I have been fine. I bought the Sharp LC-52D85U,(120hz) which is a truly matte screen. Good thing because glare would have probably triggered seizures! I have been absolutely fine. I am an over-the-hill adult who loved playing video games until I realized why I seized during certain very quick moving ones and so I ended it.


I would still consult a physician if I were in your position.
 

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Quote:
Originally Posted by Maxion /forum/post/15458802


May be a longshot, but thought I would query the wise folks here to see if anyone has any knowledge / experience with LCD televisions and seizures. A member of my family has a seizure disorder, with seizures that are triggered by light (not only flashing light, but that can be even worse). As a result, she can't really watch TV. I've heard a couple of anecdotes that people with seizures while watching TV fare much better with the new 120hz sets.


I'm getting a new set soon, and my frontrunner is the Samsung LN46A550. But if there is a reasonable shot that 120hz would allow some TV watching for someone with seizures, I'd jump up to the LN46A650. I prefer the matte screen of the 550 to the glossy screen of the 650, and that "Touch of Color" on the 650 looks like butt to me, but if it helps my kid, then I can certainly put up with it.


Any thoughts?


Thanks in advance!


Maxion

I will go out on a limb - and it is not my intent to favor one technology over another. First of all I was in the TV business for over 20 years. We also have several family members that can have seizures from different types of lighting. This is also true for certain types of TV's and Computer monitors. I have two cousins that literally have to carried out of some bigger warehouse stores (intense florescent lights and what I call airplane halogen lights).


Generally, most experts feel that the seizures are caused by the Hz and conflicts of the Hz with other light devices in the same area: for example, some people can go nearly insane, have intense headaches, or blackout when combining certain LCD panels or older CRT computer monitors; this bad effect can be multiplied many times when those panels are placed under fluorescent lighting. Also, for some people (as in our family), you can get the same bad effect (blackouts or near blackouts), even when there are no conflicting lighting sources.


Based on my own experience and those in my family that have been down that road, generally plasma sets appear to be a good choice. It is because the plasma is able to be exceptionally smooth in their light output (similar to high quality CRTs because both generate light output by the glow of the phosphor), and do not have the pulse/flicker effect that virtually all LCD panels do (either 60 or 120 Hz sets).


The real test will take place, when the person with seizures watches the different models in their own home under different lighting conditions. My experience tells me if headaches or seizures begin to occur within an hour then I would say no to that model. There are many store managers and vendors out there that will help you work out that problem.
 

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Quote:
Originally Posted by HoustonPerson /forum/post/15463823


It is because the plasma is able to be exceptionally smooth in their light output (similar to high quality CRTs because both generate light output by the “glow” of the phosphor), and do not have the pulse/flicker effect that virtually all LCD panels do (either 60 or 120 Hz sets).


LCDs have ABSOLUTELY NO flicker...they simply update the display at 60 or 120 Hz. This is infinitely better than a CRT or plasma! (in terms of flicker.) To verify this, view a TV through the blades of a fan....you will see a strobing effect with a CRT or plasma, but not an LCD.


If you had a 1Hz TV, you would see a nice steady picture that updates once per second with an LCD. With a plasma or CRT you would see a brief flash (of a few milliseconds) once per second...this would be unwatchable.
 

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Yea 120hz, 240hz and now 480hz comming from LG


The xbr7 is 240hz - 240hz xbr7




Samsung 950 and sony xbr 8 are 120hz but you should really be seeing 240 hz

when backlight scanning (led-motion-plus) is on - just an educated guess.

Somebody should make an official site with stats for folks with seizures.






Quote:
Originally Posted by HoustonPerson /forum/post/15463823


plasma is able to be exceptionally smooth in their light output (similar to high quality CRTs because both generate light output by the glow of the phosphor), and do not have the pulse/flicker effect that virtually all LCD panels do (either 60 or 120 Hz sets).

Don't LCD's use phosphors on CCFL also. Surprised to hear that since I hear people complain about plasma flicker a lot. I think the reason is that although plasma is 480hz, bright pulses are condensed.
 

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Quote:
Originally Posted by borf /forum/post/15470474


The xbr7 is 240hz

Yeah, that seems more like marketing hype than an actual improvement. Besides, 1/240 = 4mS and they claim a pixel response time of 8mS. So this is going to severely limit what it can do.
 

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Quote:
Originally Posted by caesarv /forum/post/15470864


Yeah, that seems more like marketing hype than an actual improvement. Besides, 1/240 = 4mS and they claim a pixel response time of 8mS. So this is going to severely limit what it can do.

Theyr probably using MPRT (motion picture response time) a more objective metric. It doesnt mean actual pixel response time.


You might have noticed they were comming out with 2ms LCDs for a while but that bogus measuring system actually ran out of numbers (how can you have negative response times?). They switched to a new metric in order to reflect new faster response times. From what i know its more objective now.
 

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Maxion,


I do hope you find a workable solution for your daughter and if you are able to work with a store manager to possibly have two sets in the house at the same time or at least try one at a time (for a week or so) that would help. I strongly recommend watching for up to an hour each; movies, prime time, and possibly live sports both “with” and “without” the lights in the room.


I realize there is tremendous confusion and mis-understanding on the subject particularly in regard to Hz – specifically cycles of light (and dozens of other related issues, intensity, wave length, etc). In very simple terms it is not about the 60 Hz, 120 Hz, or 240 Hz but much more about the “conflicts” on “cycles” (so it is theorized). In the case of a typical CCFL LCD panel of today’s construction that means these items are in conflict.


1. The electric current

2. The florescent backlight

3. The LCD front panel switches (liquid crystal switches is what they are)

4. Outside/Inside lighting sources

5. The eye/brain processing


As you can tell we just hit an unlimited number of “conflicting” variables. In the CRT or Plasma you eliminate one of the “conflicts”” the “backlight” – but even that within itself is an over simplification.



Side Notes:


1) If you are looking at a specific model – say an A650 Samsung, that may or may not be the same model from just three months ago. It is very common for manufactures’ to change things during a “models” production run. A production run of a model can be as short as 2 months (for a year’s supply) or as long as 6 months (very rare to go over 6 months – the technology changes that fast). Changes can be a different LCD panel used in that model, which means all those “conflicts” listed above, have just changed again. You will usually pick up on this by Rev numbers and letters next to the model number Rev A, B, or C (001,002,etc)


2) Two major different LCD panel types today: CCFL backlight and LED backlight. Those two choices could provide “dramatically” different results for your daughter. Therefore the relationship between the backlight and the LCD switches (which are also a changed because of the change to LED) is also changed dramatically (the conflicts are changed dramatically). Side Note to the Side Note: There are at least a dozen different style/types of front panel LCD switches in use today-more variables.



3) If your daughter does well in watching a CRT she may do equally well with a plasma? If she is not able to watch a good CRT set, then it would be unlikely she can watch a plasma?
 

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Discussion Starter · #15 ·
Thank you all so much for your thoughtful responses.


HoustonPerson -- we have a couple of local shops near here with some nice folks in charge. I'll explain the situation and see if we can set up an in-home experiment with a model or two, as you suggest. I really appreciate your detailed explanations, though it makes me realize that we're not likely to do any better than just to experiment.


Maxion
 
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