The eye of a cow is very similar to the eye of a human. The parts of the cow eye are nearly identical to those of a human, only enlarged. Due to this, the dissection of a cow eye leads to a better understanding of the way a human eye works in addition to the way a cow eye works.
The lens of an eye " controls 1/3 of the refraction of light that enters the eye (the cornea, the other 2/3). Located just behind the pupil it allows for changing of focus from distance to near objects by altering its shape" (http://www.pixi.com/~gedwards/eyes/eyeanat.html). The lens focusses everything a human sees. The way a lens focusses what humans see resembles the way a camera lens works. The lens in a camera puts the camera in focuss in order to take a picture that is not blury.
This experiment tests if the lens of a cow eye would make change the quality of a photograph when using a pin-hole camera. Would the lens focus better or worse than the pin-hole camera does?