Contents

1 Introduction
1.1 What these pages are about
1.2 Basic assumption

2 Lens Equation

3 Focus Distance
3.1 Minimum focus distance

4 Aperture
4.1 F-stop
4.2 Maximum aperture
4.3 Standard stop scales

5 ISO

6 Magnification
6.1 Approximation
6.2 Notation

7 Extension Tubes
7.1 Focus distance and image distance
7.2 Extending the image distance
7.3 Effective focus distance

8 Working Distance

9 Depth of Field
9.1 Circle of confusion
9.2 Limits of acceptable sharpness
9.3 Approximation
9.4 Focal length, distance and aperture vs. depth of field
9.5 Magnification vs. depth of field

10 Hyperfocal Distance
10.1 Approximation
10.2 Near limit
10.3 Practical considerations

11 Infinity Focus
11.1 Minimum object size
11.2 Merklinger’s approach
11.3 Hyperfocal distance revisited

12 Bokeh
12.1 Size of bokeh circles
12.2 Approximation

13 Accuracy
13.1 Magnification
13.1.1 Non-macro lenses
13.1.2 Macro lenses
13.1.3 Focus breathing
13.2 Depth of field

14 References