The laptop screen hosts an independent presenter’s display showing timer, enlarged notes, views of current/previous/next slides.

The external output projects a clean output: a plain selectable image (no accidentally open directories that show my Democratic National Committee clients that I also have a preso ready to go for the Republicans) until I start the presentation, at which time the first slide snaps into place and we’re off and running.

Unfortunately, this assumes that the Macbook is not running these twin framestores in “mirror” mode.  And that the remote display hasn’t somehow detected that it should be set to the resolution of a checkerboard, while the laptop display itself zooms to half resolution, sucking a lot of the necessary desktop icons back into a menu somewhere. 

All of which the computer does with no pattern I have discerned.  It seems to consult with some internal, and highly creative, muse. 

One other note - the video output is a nicely forward-looking DVI, but 90% of the projector setups I encounter are still VGA connectors (15-pin D-shell, to be exact).  So don’t forget your adapter, or you will be using your hands for shadow puppets to illustrate your talk.

I gave a presentation to a group of 100+ yesterday.  It went off without a hitch, thanks to obsessive preparation.  I recommend this:

  1. a. Go in the room before the audience arrives.  Plug the adapter to the cable

  1. b.Plug the adapter, with cable already attached, to the computer (don’t do this in reverse, because the computer seems to sense the adapter alone, then re-sense when you plug the projector in). 

  1. c.  Set up the computer and display modes.  This may require screen-sensing, changing mirror mode, resetting resolutions, invoking displays under the apple-systemprefs menu, and/or the use of words containing family-unfriendly sibilants and fricatives.   Allow lots of time for this preparation - ten minutes should be good if you’ve been screwed by all this before and know the buttons, a half-hour if you haven’t.

  1. d.Start your presentation (enter presentation mode), show yourself a couple of slides, be comfortable with the result on both displays. 

  1. e.Exit full-screen mode.  THIS IS ESSENTIAL!  Never connect/disconnect a projector, or open/close the computer,  while in full-screen mode!  The Macbook has a special coprocessor chip that detects Fullscreen+unplug/sleep and then sticks its thumb in random bits in the video configuration tables, leading to even greater confusion.  (Legal disclaimer: It probably doesn’t, it just feels that way).

  1. f.Reverse steps b, then a, in that order.

  1. g.Close the computer, let it sleep.

  1. h.Now the most important step:  Repeat steps a through d in front of the empty room.  If this works, you have a pretty good chance of getting through an on-stage setup safely. 

But just in case, prepare a couple of humorous remarks to have within reach.