LCD Refresh rate on the eyes

Figment

Hi,
I need to work on a LCD screen at 1600 x 1200 resolution. However my graphics card can only run that resolution at 60hz.
What effect will that refresh rate have on my system and my eyes?
I know if i run that on a crt screen i will have a headache within 5 mins and need glasses after 10. But looking at the LCD and no eye strain yet.

Al

Kali

err none. refresh rates don't apply to LCD screens, and they don't flicker so theres no eye strain regardless of resolution... just make sure you use the screens native (reccomended) resolution and you'll get the sharpest image, any smaller res and the screen has to start doubling up pixels.

seamus

Hehe, there's a guy who works with us that claims the LCD screen hurts his eyes, and puts a filter in front of it. It gets strange looks anytime someone see its.

Figment

Ok, Thanks guys. Just making sure.
Would it effect the frame rate of full screen video playback?

Stark

There are some poor quality LCD screens that are absolute murder on the eyes. Used to work in a computer lab before where they bought a load of the things en masse and couldn't look at them for more than 10 minutes before my eyes were all watered up from the strain. Move your head even slightly compared to the screen and it would be like a wave sweeping across the monitor.

Kali

Originally posted by Figment
Ok, Thanks guys. Just making sure.
Would it effect the frame rate of full screen video playback?

Affect the framerate directly? no not at all.
But if you doing video editing or working with movies than be aware that even the best LCDs at the moment do still have a noticeable ghosting effect with any onscreen motion.. I'm presuming its at least a 19" due to that high resolution, and therefore most likely a 25ms response time.
And that fact may make it more difficult to differentiate between framerates and associated quality/smoothness (if you are actually working with video).

red_ice

Originally posted by Kali
Affect the framerate directly? no not at all.

(im just awake, excuse me)

Your explination is telling a half truth there kali - LCD Screens dont effect framerate of a card or what not, because a monitor is kinda like a periferal, in the sence that you cant directly effect the performance of a computer with it.

But when the monitor cant refresh as much as the graphics card wants it to, the frame rate is effected via your monitor.

Kali

Originally posted by red_ice
But when the monitor cant refresh as much as the graphics card wants it to, the frame rate is effected via your monitor.

Quite true, but he was (I presume?) refering to (and my post referred to) full-screen video playback and not fps-based games or such... the former not needing anywhere near the maximum bandwidth that an LCD screen provides.

Figment

full-screen video playback and not fps-based games or such

Yep.
Its a 21 inc monitor.

Thanks all for the replies.

Cabaal

Originally posted by seamus
Hehe, there's a guy who works with us that claims the LCD screen hurts his eyes, and puts a filter in front of it. It gets strange looks anytime someone see its.

There's a good few people in one of the departments where I work that use those screens on LCD's, bloody muppets!
They just don't understand...
sigh.... :rolleyes:

Giblet

Shit LCDs hurt my eyes.

Big Chief

Originally posted by Kali
err none. refresh rates don't apply to LCD screens, and they don't flicker so theres no eye strain regardless of resolution... just make sure you use the screens native (reccomended) resolution and you'll get the sharpest image, any smaller res and the screen has to start doubling up pixels.

ahhhhh!

if i turn my tft down from 1280x1024 to a lower res then it starts to look "different", didnt know this was the reason for it... cheers

red_ice

Originally posted by red_ice
(im just awake, excuse me)

Sorry, im a performance freek when it comes to computers! i dont settle for anything less that 100hz, im runnign 120 atm.. also, my 3200+ needs an upgrade

So i was really looking at it from that angle, if you want practicality, LCD all the way

leeroybrown

The only thing that affects TFT performance (apart from the image quality variance of different displays and the connection type) is (as mentioned above) the response time.

The Response Time is the sum of the rise and fall times of the individual transistors.

For a 15"/17" display 16ms
For bigger I Think 25ms is still the norm

This means that the best refresh rate the transtors of the display will actually show you is:

62.5 Hz for a 16ms display

But because the transistors don't visibly flicker this isn't a problem. The only issue you will see is Ghosting which is related to the amount of time it takes an individual transistor to change colour during rapid changes. With 16ms response time you'll barely notice it.

The other thing that will improve TFT performance is a DVI input rather that Analogue D-15 (This requires Digital -> DAC -> Analog -> ADC -> Digital obviously causing some minimal loss of signal clarity).

Matt Simis

I imagine the lack of DVI inputs (or lack of use) is the problem that people who claim LCDs "hurt their eyes" are experiencing. Analog on LCDs generally looks quite bad.



Matt

leeroybrown

In my experience any poor TFT's I've used have been Analog, but while I think that having a DVI input is far better, I would lean more towards the argument that the Analog only models are either older or lower budget designs, hence the problems.

acous

Originally posted by red_ice
i dont settle for anything less that 100hz, im runnign 120 atm

it'd be interesting to see if you could tell the difference between 120fps and the equivilant of 60fps on a 16ms lcd ( i.e. 120fps with every second frame being a 50% dissolve between the previous and next frame). anyone know if there's been any studies done on that?