When using the arcs in an octogonal base we get a new model for dome 5.

The result in the model isn't a smooth convex dome. This is due to the use of lines for the arcs and a dome surface that follow these lines. On photographs we can clearly see that in the realisation of the dome the arcs are altered to get a convex come.[br]Furhtermore in the dome the arcs aren't lines at all, but arcs with a consideral thickness which makes that in the realisation the axes of the dome are in fact shifted a bit away from the midpoints of the sides of the octagon, so reality an surface of the defined polygones differs from this line scheme. [br]We allso se that he triangles around the central octagon on the plan are in reality minimised and filled up in a way that in the vault you can almost ignore them as an independent dome surface to cover.[br]On the arcs that were used in Toledo we can say that pictures don't show pointed arcs but rounded arcs. However by altering the heights of the ribs we could create dome realisations with different kind of arcs.

See how the dome surface doesn't follow the line scheme of the arcs. [br][list][*]in red: You can clearly see that the ribs are altered to sustain the convex dome.[/*][*]in blue: You can clearly see that the triangular faces are minimal.[/*][/list]