Both Lightroom 3 and Photoshop CS5 has capability of using dual monitors. I am using a laptop with the larger monitor mounted above it.
I have them working together properly in Lightroom 3.
I have been unable to get the Photoshop CS5 combination to work together properly. The image should be on the
large monitor, and be influenced by the comands from the
computer. I have just the opposite; wallpaper and the photoshop panels on the monitor, and just the image on the computer. (I can't understand that myself so I will try to show photos of the condition.)

This one correct Lightroom 3


Does not work Photoshop CS5

I have been photographing for a long time.
Used a lot of different formats 35,6x6,4x5.
Now use a lot of software; PHOTOSHOP CS, PHOTOSHOP
ELEMENTS 6 & 8, PHOTOSHOP CS 5, and LIGHTROOM 3.
I don't care for LIGHTROOM 3.
Wish I didn't need a computer to use the software.

Jarrettsville