This activity shows how to produce an infrared composite image such as NRG, where the Red and Green channels of a picture are displayed in green and blue, respectively, and the color red is used to display a new channel -- near-infrared. ##Using Photoshop to do vegetation analysis with your pictures## You can use Adobe Photoshop or another image manipulation program to composite an infrared and visible image to do vegetation/photosynthesis analysis. _To complete this activity, you'll need:_ * source images, from the close to the same angle, taken at close to the same time * one source image from a normal camera * one source image from a camera modified to take near-infrared images * Adobe Photoshop or the open source alternative, (GIMP)[http://gimp.org]. For some Macintosh users, [Pixelmator](http://www.pixelmator.com/) is a powerful but lightweight option by an independent software company. * about **30 minutes** the first time; about 10 minutes once you get the hang of it ###Video Tutorial### Watch this 10-minute video explaining how to align and composite your two source images. The example photos were taken from an airplane window by Stewart Long.