Hace tiempo navegando me crucé con una página con muy buena información y explicaciones ópticas estrictas sobre diferentes fenómenos que afectan o que nos encontramos dentro de la fotografía, incluyendo referencias bibliográficas.
Hace poco la quise volver a consultar para responder alguna consulta y no pude encontrarla. Hoy me iluminé y la pude buscar y encontrar entre los cientos de bookmarks que tengo.
Va especialmente dedicada a Luigis y todos aquellos fanáticos (como yo) que se deleitan con explicaciones físicas y ópticas detalladas.
LinkAlgunos de los temas que trata, con muy buenas explicaciones y nivel, casi de física de facultad diría, son:
Seidel aberrations- Spherical aberration occurs when the lens margins focus the light closer to -or further from- the sensor than the lens center.
- Coma is associated with off-axis image points being smeared out in the characteristic comet shape.
- Astigmatism implies that a lens can be sharper in one direction than another. The archetypal example is that of a wheel where the spokes and the rim are not rendered sharp simultaneously.
- Field curvature leads to a curved image surface. Although the image can be sharp on this surface, it is incompatible with a flat sensor.
- Distortion is not a sharpness issue but leads to straight lines in object space being rendered as curved lines on the film.
Color errors- Chromatic aberrations are due to dispersion and lead to color fringing.
Other phenomena and effects- Vignetting is the gradual or abrupt darkening of an image towards the corners. A related page discusses lens hoods.
- Flare is the collective name for colored spots, ghost images or veils that impair the image. A separate page further exemplifies filter flare.
- Diffraction is an unavoidable law of nature that says that a beam of light with a finite diameter spreads out as it propagates. It sets the ultimate limit to the resolution of a lens.
- In focus: an article on depth of field, the theory and a DOF calculator.
- Out of focus: the arcane bokeh.
- Spurious resolution, a pitfall in lens resolution measurements.
- On the center of perspective of a compound lens.
Y al final hay un apartado de
falsas creencias en la fotografía.
Espero la disfruten.
Saludos
