Because neither I nor my software are very sophisticated, these pictures are assembled from screenshots which explains why the 3D views of the parts are not consistent.
The picture below right is a from an ad on the net for a very expensive HAL recreation. I have used it to get the proportions of the thing more or less right given that the diameter of the lens I have is fixed. I think a real lens makes the thing look more authentic even though it is not quite like the fisheye on the original.
