Most important LCD parameters for text use

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"Top Spin" <ToppSpin@hotmail.com> wrote in message
news:cba2h05tgdv9tj5khn0smlsuaeuqu2g8rk@4ax.com...
> What are the most important parameters for an LCD monitor for text
> use?
>
> Contrast ratio? Minimum of 400:1? 500:1? more?

Contrast ratio is a much-abused specification; generally what
is being quoted is a figure that couldn't possibly be achieved
in real-world ambient conditions (meaning something other
than what you'd see using the monitor at the bottom of an
unlit coal mine at midnight on a moonless night). The dominant
factor in real-world delivered contrast is almost always reflected
ambient light. The point here is that the specs need to be taken
with a rather large grain of salt in most cases. Having said
that, we also need to note that human vision itself has a limited
dynamic range (which is what contrast is all about in the first
place), so any delivered contrast ratio in excess of somewhere
in the low hundreds to one is going to be "good enough."
(Another way to look at this is to say that there is a huge
visible difference between, say, 100:1 and 150:1, and almost
no difference at all between 400:1 and 600:1, as seen by the
viewer.) Bottom line - if you like the looks of it in an environment
similar to what you're going to be using it in, don't worry about
the numbers.

>
> Brightness? 250? 260? 270? Higher?
>

Again, this is very dependent on the ambient environment - we
do not see "brightness" in absolute terms, but rather how bright
the image in question is with respect to its surroundings (which
has to do with the current adaptation of the eye). Having said
THAT, most users will be comfortable, in a typical home or
office environment, with a display luminance (technically,
"brightness" is something slightly different) in the 200 to 300
cd/m^2 range. Keep in mind that the vast majority of our
old reliable CRT monitors delivered luminances typically in
the neighborhood of 100-120 cd/m^2.

> Refresh rate? Does this even matter for LCDs?

Not really, at least not for the same reasons as it did with
CRTs. An LCD display is essentially flicker-free at 60 Hz, and
that rate is certainly adequate for very good motion (as is
demonstrated by TV), so there's no reason to push for anything
higher except in some very unique cases.

>
> True number of colors?
>

For text work, you're not likely to care all that much, and almost
any LCD monitor is going to give you at least 6 bits/primary
anyway (which is pretty good) and many give 8. (We're going
to want more bits/color at the panel in the future, though, for
some other reasons.)

> Response time? Does anything under 25ms matter?

Again, for text work, probably not.

>
> Viewing angle?
>

How important is having other people see the image well
at the same time as the primary user?


Bob M.