(Different) Optical Constructions of the Four DA18-55 Zoom Lenses

Source: http://forum.xitek.com/thread-866434-1-1-1.html (in Simplified Chinese)

1. Original DA18-55 - 12 Elements in 9 Groups, One Aspherical Element:





2. DA18-55II - 11 Elements in 8 Groups, One ED (Extra Low Dispersion) Element:





3. DA18-55WR - 11 Elements in 8 Groups, One Aspherical Element and One ED Element:





4. DAL18-55 - 11 Elements in 8 Groups, No Aspherical nor ED Element of