How to use an lcd projector

There are two ways of setting up the desktop on systems with multiple displays. One method is called Cinerama. In this mode, the system has two virtual desktops, which should be thought of as halves of a single large desktop. There is a left pane, and a right pane, and items exist entirely in only the left pane or the right pane, unless the user moves items onto the dividing line between the two panes. Maximizing a window will only stretch onto the pane where it is based. Believe it or not, some people find this method of operation useful for using programs like Photoshop, where there are many small windows with adjustable controls, and a single large window with which to see the results of those changes.

Most people don't want Cinerama mode when they want to give a presentation using a program like Powerpoint. If they chose to display Powerpoint in Cinerama mode, they would first need to launch Powerpoint, and move it into the window being displayed on the projector. Then, they would have difficulty knowing which slide they were on without breaking eye contact with the audience to look at the screen.

Before reading the instructions, check to see whether you have an F7 button which also is labeled with what looks like two boxes. This may serve as a shortcut to get to the settings I describe below.

1. Click the Apple menu, usually in the top left corner of the screen, and choose System Preferences.
2. Click the button for Display. It should look like this



3. You may have a window pop up that tells you about your settings for your lcd display (assuming you're on a laptop). Ignore or minimize this window.
4. On the Display window, choose the box labeled Arrangement



5. Check the box that says Mirror Displays
6. You can now close System Preferences if you desire.

The Math Department official policy is that we do not support linux laptops. However, if you really wanted to try to do this, I would recommend two plans of attack:

1. Reboot the system, hit whatever key sequence is needed to enter your bios, and look for an option to allow you to boot the system with the external video port rather than the onboard lcd. This may break your X settings, but there's a chance you'll get lucky. Obviously this would mean that you wouldn't be getting the same video on your lcd, as the lcd would be disabled.
2. If you want video on your lcd AND your external video port, you'll need to modify your X configuration file. For systems with Xfree86, this is often /etc/X11/XF86Config, and for systems with X.org this is often /etc/X11/xorg.conf
   
   Refer to google for your specific laptop to see if somebody has already posted the specific X settings to get your external video port working properly. If you don't find a google hit for your laptop and you get it working, post your settings on your website so that other people can use your settings, and so you can remember how to set things up if you ever reinstall your OS.