Video Projector

[Paul Johnson]

On Wed, Dec 10, 2008 at 1:19 AM, Richard Brown <rich at cregy.co.uk> wrote:
> Hi All
>
> I am just about to purchase a video projector and I have to admit I
> can see no reason why a video projector wouldn't work with Ubuntu...
> but just in case has anybody had any experienced of running a Ubuntu
> set-up and a video projector. Has anybody any thoughts on what
> projector to buy. I was looking at this:
> <http://www.amazon.co.uk/Sony-VPL-ES5-Video-Projector/dp/B0016623T8/ref=sr_1_1?ie=UTF8&s=electronics&qid=1228834776&sr=8-1>
>
>

I find it is MUCH easier if the resolution of your computer matches
the resolution of your projector.  If they are different, especially
if the projector is much lower in resolution, then it will look bad in
Linux.

Other posters have told you that this is not an operating system
problem, but they are not exactly giving the full story. It is not a
Linux kernel problem, but it IS a video driver problem, and there are
differences across video drivers in the quality of support they have
for video output.

Newer cards and Ubuntu will support the xrandr extension, which allows
you to interactively control the output on different devices. You can
see if you have it enabled by opening a terminal and typing

$ xrandr -q

Screen 0: minimum 320 x 175, current 1400 x 1050, maximum 1400 x 1050
default connected 1400x1050+0+0 0mm x 0mm
   1400x1050      50.0*    51.0     52.0     53.0     54.0     55.0     56.0
   1360x768       57.0     58.0
   1280x1024      59.0     60.0     61.0
   1280x960       62.0     63.0

You can read xrandr help pages, but basically the idea is that when
you plug in devices, they will show up in this listing as LCD1 or
whatever, and then you can tell them to "turn on" with a command like
this to turn on 2 outputs, the "default" and "VGA"

xrandr --output  default --mode 1280x1024 --output VGA --mode 1024x768

 It is a nice way to experiment, but I've not yet found a simple GUI
controller for it that will work on all video devices.  Nvidia's
proprietary driver supplies a program "nvidia-settings" that is
somewhat like the MS Windows controller that can turn on and off the
external monitors.  If that doesn't work, then you have to go old
school and use the TwinView configuation in xorg.conf  if you have the
Nvidia card.  On ATI cards, the output to the external device was
different.

If you could possibly test out the projector before you buy, you will
be happier.  In almost all cases, I've found that I can get projectors
to work, but on some of the old/crappy projectors we are assigned
around the University, then there is trouble because the projector
cannot take the high resolution, high speed of a newer laptop.  The
mismatch may be attributed to the poor drivers available for some
video cards in Linux. I wouldn't worry too much if you have a main
brand video card like Intel, Nvidia, or ATI.  But if you have "Joes
House of Electrons" in your system, then you should be cautious.  The
video modes of the laptop's output are controlled by the video driver,
and my experience is that the Linux drivers are not so well polished
as the Windows drivers.  Maybe, since ATI and Intel are open to
community involvement, it is getting better for them. But on my Nvidia
systems, it's been an adventure. Luckily, Nvidia supplies a huge text
README file with tons of details and they have a very lively linux
forum where you can ask questions.

pj


-- 
Paul E. Johnson
Professor, Political Science
1541 Lilac Lane, Room 504
University of Kansas