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Optics pages

   I. Spherical aberration

1. Focus shift

2. Out-of-focus character

3. Concluding remarks

  II. Astigmatism and field curvature

1. Spoked wheel

2. Curved surfaces

3. Astigmatism in practice

4. Final remarks

 III. Distortion

1. Origin

2. How to read a distortion graph

3. Distortion in practice

4. Perspective

  IV. Chromatic aberrations

1. Longitudinal and transverse chromatic aberration

2. Examples

3. Secondary spectrum

4. Achromatic lenses

5. Purple fringing: lens or sensor?

   V. Vignetting

1. Optical vignetting

2. Cat's eye effect

3. Natural vignetting

4. Mechanical vignetting

5. Remedies

  VI. Lens hoods

1. Size of the hood

2. Influence of hood length on vignetting

3. Shape of the hood

4. Final remarks

 VII. Flare

1. The bright sun

2. Aperture ghosting

3. Veiling glare

4. Filter flare

5. Final remarks

VIII. Filter flare

  IX. Depth of field

1. Definition

2. The concept of DOF

3. Viewing conditions

4. Circle of confusion

5. Visual acuity

6. DOF versus distance

7. DOF versus focal length

8. DOF at constant magnification I

9. Background blur

10. DOF at constant magnification II

11. Foreground blur

12. Macro depth of field

13. DOF at constant magnification III

14. Digital depth of field

15. Flashlight and ghosts

16. Hyperfocal distance

17. Depth of field preview

18. Depth of focus

19. Sensor dust

20. Limitations of the geometric model

21. Conclusions

Yes, this page is boring. But at least it provides links to individual paragraphs, which can be used to direct people to particular sections.

   X. Derivation of the DOF equations

1. Pupil magnification

2. Geometry of image formation

3. The equations

4. Hyperfocal distance

5. Image magnification

6. Depth of focus

7. Background blur

8. Symmetrical lenses

  XI. VWDOF calculator

 XII. Bokeh

1. Introduction

2. Characterization of the blur disk

3. Amount of blur

4. Shape of the blur patch

5. Lens aberrations

6. Onion rings and dust

7. Concluding remarks

XIII. Spurious resolution

 XIV. Misconceptions

1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10

Use of the front element.

 XV. Center of perspective

1. Perspective

2. Panoramic stitching

3. Influence of lens asymmetry on the field of view

4. Conclusions

 XVI. Notes on MTF measurements.

1. Introduction

2. Considerations

3. Image magnification

3. Case study

5. Concluding remarks

 XVII. Corrections in digital imaging.

1. Introduction

2. Deconvolution

3. Case descriptions

4. Verdict

Publication list