# Photographic Lenses Tutorial

This tutorial contains a summary of optical facts for photographers. It is more detailed that a FAQ file, but less so than a text book. It covers focusing, apertures, bellows correction, depth of field, hyperfocal distance, diffraction, the Modulation Transfer Function and illumination.

This Photographic Lenses Tutorial about was compiled and written by David M. Jacobson with contributions by others.

This note gives a tutorial on lenses and gives some common lens formulas. I attempted to make it between an FAQ (just simple facts) and a textbook. I generally give the starting point of an idea, and then skip to the results, leaving out all the algebra. If any part of it is too detailed, just skip ahead to the result and go on.

It is in 6 parts. The first gives formulas relating object (subject) and image distances and magnification, the second discusses f-stops, the third discusses depth of field, the fourth part discusses diffraction, the fifth part discusses the Modulation Transfer Function, and the sixth illumination. The sixth part is authored by John Bercovitz. Sometime in the future I will edit it to have all parts use consistent notation and format.

The theory is simplified to that for lenses with the same medium (eg air) front and rear: the theory for underwater or oil immersion lenses is a bit more complicated.

01. Introduction
photo lenses tutorial: 01. Introduction
02. Object distance, image distance, and magnification
photo lenses tutorial: 02. Object distance, image distance, and magnification
03. Apertures, f-stop, bellows correction factor, pupil magnification
photo lenses tutorial: 03. Apertures, f-stop, bellows correction factor, pupil magnification
04. Circle of confusion, depth of field and hyperfocal distance.
photo lenses tutorial: 04. Circle of confusion, depth of field and hyperfocal distance.
05. Diffraction
photo lenses tutorial: 05. Diffraction
06. Modulation Transfer Function
photo lenses tutorial: 06. Modulation Transfer Function
07. Illumination - The Photometric System
photo lenses tutorial: 07. Illumination - The Photometric System
08. Illumination - Photometry with a Photographic Light Meter
photo lenses tutorial: 08. Illumination - Photometry with a Photographic Light Meter
09. Illumination - Image Illumination
photo lenses tutorial: 09. Illumination - Image Illumination