[thelist] wish list

rytames at telusplanet.net rytames at telusplanet.net
Wed Jul 2 05:10:59 CDT 2003

On 1 Jul 2003 at 23:16, Joshua Olson wrote:

> > Any CRT running at less than 72-75 Hz is unviewable for anything
> > longer
> than
> > short stints once you have got used to good quality, high refresh
> > rate monitors, because the flicker is visible.
> Are you referring to when the monitor is used in a room with
> flourescent lighting.  Respectfully, I notice no flicker in my

I just changed my monitor to 75Hz, well, my eyes have relaxed,
I can see better.

Correct me if I am wrong, Flourescent lighting illuminates at 60Hz, which
I gather is due to electron flow of 60Hz. Which gets me thinking about
electronics, I just decided it must be due to compacitors.

What I was going to say was, you don't consciously see it, or
hear the frequency, as your mind does the best it can to 'filter' out
the visual noise, and I gather, the eyes and mind work togther
to create a perception of fluid movement, along with persistence
of vision.

Anyway, my point is, we sample movement at a higher rate
then 30 fps, and also higher then 60Hz, I forget the number, but I
think we can see clear movement as high as what would be equavilent to
78fps, above that it becomes a blur.

At any rate, the flicker cuases physical stresses, probally mostly
on the retina, and iris, as I gather, they need to respond more
to changes in the lighting, as the monitor has a lower flicker rate,
but has technology bult into it that reduces the flicker, by increasing
the bandwidth.

I gather Theatre takes advantage of the speed of light, distance of the screen 
from the light source, and the construction of the framed film. And of
course electronic-mechanical difficulties would need to be considered.

TVs use interlaced scans, at near 30fps, where the electron guns
stimulate a horizontal line of phosphers, though the difference is,
it scans only half the horizontal 'pixels' every 30fps; Scan lines
1,3,5,7,9,... first, and then scan lines 2,4,6,8. Odds and evens,
which are the fields. Which take advantage of the phosphers,
and retina in the human eye; I think.

I am not sure about the technology monitors use, as there 
still exists a strobe like effect, as one can see by pointing 
a movie camera at a monitor. I gather, but am totally unsure,
but I think, it uses  fields as well, but in this case maybe
starting at the top (??bottom??) and writing multiple scan lines,
requiring more bandwidth. I think the phosphers are different as well.

I find the whole thing rather confusing, especially when I begin
thinking about multmedia applications over various media,
and the conversion of the data from - to various media, while
keeping the audio/video syncronised, even by indirectly increasing the
bandwidth by compression, vector formats, or contextual formats...

I must say, there must be one piece that I am missing.


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