I tried the 15/4.5 in the Nikon F non-retrofocus version, also on the Z cameras. This version is rarer than the L and both smaller and bigger at the same time, as it sticks deep into the camera throat but exposes a very flat exterior. There is some vignetting by the non-retrofocus design, however, so I mostly use this lens on my Z fc. A nice lens in either design (I sold off the L39 model when I ceased to use film).