Mona Lisa of the North

Does she turn towards you or away from you? They disagree. She is the mysterious person in the 'Girl with a Pearl Earring' by Dutch grandmaster Johannes Vermeer. The painting is often called the 'Mona Lisa of the North'. But what makes this painting so fascinating? 
 
In cinematography, perspective distortion is a warping or transformation of an object and its surrounding area that differs significantly from what the object would look like with a normal focal length, due to the relative scale of nearby and distant features. Perspective distortion is determined by the relative distances at which the image is captured and viewed, and is due to the angle of view of the image (as captured) being either wider or narrower than the angle of view at which the image is viewed, hence the apparent relative distances differing from what is expected.