

Designers Guide To DPI - ismavis
http://sebastien-gabriel.com/designers-guide-to-dpi/

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ricardobeat
One comment about frame rates: the only reason 120hz looks better (and exists
at all in our current TVs, even up to 600hz) is LCD panel response time and
ghosting.

A standard movie, shot at 24 or 30fps, looks better in a 120hz screen vs a
60hz one, even thought there are still only 24 different images to be
displayed per second, and both refresh rates are much higher than the
available frames. A higher refresh rate means the screen can switch between
frames faster, so it's actually displaying repeat frames, but the reduced
ghosting makes everything look sharper and smoother.

In addition to that - ignoring the snarky paragraph underneath the picture -
the example given where you have more intermediate states only applies up to
60-66fps; after this point humans are unable to detect any difference, due to
~15ms of visual delay and afterimages (ghosting!). People often mention
studies where someone was able to detect an image displayed for 1/200th of a
second or similar durations, but that doesn't mean that person can tell apart
a _moving image_ at 60fps vs 200fps. Our eyes have no shutter; we can capture
light that was visible for way less than 1/60 of a second, but as soon as it
starts moving our hardware limitations show up.

~~~
gmurphy
Here's quick demonstration that you can easily detect 60fps and that the
referenced picture is valid - grab a window (or even your mouse cursor) and
wiggle it around your screen. Unless your computer is ancient, it was probably
updated at 60hz. Yet it's not very smooth - you can clearly see multiple steps
with gaps in between.

Now do the same on a 144hz monitor - it is significantly different, but still
not as smooth as it could be.

