Frittering around on the Lynda website looking for Illustrator assistance when I saw this featured on the home page:
Welcome
Foundations of Photography: Exposure | by Ben Long
View this entire course and more in the lynda.com Online Training Library®.
I like Matt Kloskowski's pieces on Layers and other Photoshoppery at Kelby Training, but man, how much Lynda has changed since I last relied on her! The supplemental graphics to help explain the concepts were all I needed to push me over.
Lynda, sorry I strayed, my dear!