3 ms·
"30 fps flicker" - that's not a CRT, it doesn't flicker, because unlike CRTs, a flat display doesn't have a ray refreshing the display top to bottom. And 30 fp
by mantraxB 12y ago
"30 fps flicker" - that's not a CRT, it doesn't flicker, because unlike CRTs, a flat display doesn't have a ray refreshing the display top to bottom.
And 30 fps on a CRT wouldn't be enough to produce stable image in the retina at all, which is why CRT TVs used to refresh at a minimum of 50Hz, and that still flickers (it stops "flickering" at around 75Hz).
With flat displays frame rate is about display responsiveness and animation detail.
So I wonder where are the claims about eye-strain coming from. Maybe because people just want better display responsiveness and they like to borrow from the problems low refresh CRTs used to cause, because it sounds scientific and legit as a problem.
- astrodust 12y agoPersistence of vision depends on the ambient brightness. Movies are 24FPS but they're shown in a dark room so the jitter isn't as bad. A 30FPS screen in similar conditions wouldn't be as bad, but most people use computer screens in well it rooms. The flickering on an LCD is different, but presents itself as a serious sputtering when you're moving things around.
- mantraxB 12y agoWell ambient brightness matters, but actually analog cinema projectors use a frame rate of 48 fps (they "flick" every movie frame twice), so it's still way above 30fps. Plus, with CRTs the problem is exacerbated, because they scan top to bottom, and need higher refresh rate to hide this effect.
- mark-r 12y agoFilm is projected with a shutter operating at twice the frame rate or better, to minimize flicker. It would be unwatchable otherwise. See http://en.wikipedia.org/wiki/Movie_projector#Shutter http://en.wikipedia.org/wiki/Movie_projector#Shutter