Display options on Visualisation screen
The Field of view is the extent of the rendered model that is seen on the display at any given moment. It affects perspective in the view. A low Field of view value such as 10° is similar in effect to using a telephoto lens which "flattens" perspective, giving an effect more like the isometric view used on the model edit screen. A high value like 90° allows more of the model to be seen on the screen at any one time which can be especially useful for interior views. However this does exaggerate the effect of perspective giving distorted angles. These effects can be seen in the screenshots below.
Field of view = 10° (telephoto with flattened perspective)
Field of view = 50° (normal view, default setting)
Field of view = 90° (wide angle with exaggerated perspective)