Links

Optical Depth (Isothermal Atmosphere)   - Details
Wolfram Research

Optical Depth   - Details
Wolfram Research, propagation

Image Formation by a Diverging Mirror   - Details
U of Otago, Gamelan Java Applet

Image Formation by a Diverging Lens   - Details
U of Otago, Gamelan Java Applet

Image Formation by a Converging Lens   - Details
U of Otago, Gamelan Java Applet

Measurement of Imaging Properties   - Details
University of Edinburgh in PDF

Imaging of Extended Objects   - Details
University of Edinburgh in PDF

Depth of focus   - Details
Göran Manneberg, The Royal Institute of Technology, Stockholm

The principal plane   - Details
Göran Manneberg, The Royal Institute of Technology, Stockholm

Imaging in a thin lens   - Details
Göran Manneberg, The Royal Institute of Technology, Stockholm