General Projection Information:

 

Projector Central

http://www.projectorcentral.com

 

Projector People:

http://www.projectorpeople.com/

 

Rose Brand Projection Blog

http://blog.rosebrand.com/category/Projection.aspx

 

 

Projector Calculators:

 

Projector Central

http://www.projectorcentral.com/projection-calculator-pro.cfm

 

Christie Digital

http://www.christiedigital.com/en-us/product-support/throw-distance-calculator/pages/default.aspx

 

Barco

 http://www2.barco.com/en/media_entertainment/lenscalculator/

 

 

Screen Manufacturers:

 

DaLite

http://www.da-lite.com/markets/events

 

Strong/ MDI

http://screen.ballantynestrong.com/

 

 AV Stumpful

http://avstumpfl.com/en/projection-screens/

 

Screen Works

http://www.thescreenworks.com/

 

Harkness

www.harkness-screens.com

 

Rose Brand

http://www.rosebrand.com/

 

 

More:

http://bruce.pennypacker.org/2009/10/17/diy-dmx-dowser/