Question

In this question we are testing the geometric and chromatic aberrations we have studied. Use a cell phone camera or a web camera to capture an image of a white sheet of paper with your name on it.

- Does your image show an instance of geometric aberration?

- Does your image show chromatic aberration? Print your image and Mark the locations of these effects in the images. You can take images of other objects or scenes to show these effects if the image of the white sheet of paper did not show it.

Answer 1

For understanding the abberations, we will be looking at some of the images with abberations.

Geometric Distortions are caused due to the shape of the lens and are more prominent when you take shots from a very wide angle lenses. This is an example of the image.

(Reference : http://slicedtomato.net/wp-content/uploads/2010/07/FUBellTowerLeaning.png)

In this image you can see that the tower doesn't look straight and is curved slightly, this is Geometric abberation, which was caused due to the shape of the lens.

Chromatic Abberation is caused due to the property of the light ie. Light consists of different components of wavelength, which causes each wavelength to have a specific refractive index as it passes through the lens, and when the light rays come out of the lens, they won't converge at the same focal point leading to abberations in the image.

Take a look at this image :

Source : Google Images

Here you can see that the image appears to have different shades of colour at different places of the image, this is due to the effect of chromatic abberation.