[Webmonkey]

Dear all,



I have been comparing some CRT specs over the last couple o days.



Can anyone tell me what RGB bandwidth is and what does it mean???


Is it important??


(I am specificaly thinking of the 75MHz of the Barco 808 vs. the 120 of the 808s)

 

[Chuchuf]

The higher the bandwidth, the better, to a point.


Terry

 

[Webmonkey]

ehm, does that mean better colours???

 

[pcCinema]

Higher resolutions possible, tighter focus, potential for more detail to be displayed...


Troy

 

[Curt Palme]

I'm not sure about better focus per se, but think of it as the treble control on your stereo. The more bandwidth, the more treble, and therefore the more detail in the picture.


Curt

 

[Dizzman]

Think of bandwidth as the electrical pipe leading into your display. If you signal is HDTV, then you need about a 50-60 MHz pipe to display it correctly. If you have a smaller pipe, (30-40 MHz) then while the signal will get there, it will be a little distorted. IE, a charachter that is supposed to be very sharp (turn on very quickly then off, like a vertical line) will be a little fuzzy.


If you have insufficient bandwidth, then you will never get it quite sharp enough.


Read this for more info if you like...
http://www.extron.com/technology/archive.asp?id=vidband

it is the first part in a 4 part series. Link to part 2 is at the bottom of the page

 

[pcCinema]

Yes I cringed when I read my own post... I should have been more specific, that I was speaking in general. The better the pj typically genrally usually sometimes possibly maybe the tighter the focus. ymmv


Troy

 

[masters]

from cybertheater.com

Quote:

Bandwidth is closely related to horizontal resolution. Regardless of the CRT spot size and optical characteristics of the lenses, the RGB signals must arrive at the CRTs with sufficient bandwidth to modulate the beam current at a rate (frequency) that creates the high resolution light to dark transitions of the image. The frequency response of the projector's electronics will degrade the frequency bandwidth of the HDTV signals unless the projector bandwidth is considerably higher than the HDTV signal bandwidth. If that happens, horizontal picture resolution will be lost.

There is a chart on the page that list the max RGB bandwith required for several resolutions.

 

[rob47v]

Wow Masters thats the best explanation I've heard so far. Now things make sence to me. The higher the bandwidth the hotter the signal thus brighter and sharper image simple right.