This is only my second major attempt on modelling a realistic human head, and one of the few tries to do any organic modelling at all. My first head dates from 2006 and since then I left the subject to continue what I do most of the time.
Back then I found about a spline modelling tutorial by this forum user 'neversong', and this is where I got the idea from. I didn't use spline modelling though, just polygonal.
I focussed to keep a clean topology, but when the edgeloops from the eye and mouth area came together, I ran into some difficulties. To make this all happen, I added a few more edgeloops, so I could get a smoother result around the side of the head. But when I added more edges to define the noseshape better, the mesh at the center of the head became too dense to easily control it. This resulted in some bumpy areas, and a blocky looking top of the head.
I tried to reduce the amount of edge loops at the center of the head by using some nasty tricks, but I seriously think this is not the correct method.
Any comments of more advanced head modelers would be very welcome