Over the past few years, I have bought 3 modern Zeiss lenses for use on my Sony 7S with a Canon EOS to Sony adapter. All are in Zeiss' Z range (i.e. not the absolute latest range of lenses like the Milvus etc but ones which are more of a classic optical design). The lenses are the 50mm f2 Macro Planar ZE, the 85mm f1.4 Planar ZE and most recently the 35mm f1.4 Distagon ZE. In each case these are moderately expensive lenses so I sold something else to help fund these including (sob) some Leica glass that I have owned for many years and got good use from (but, time to move on! I am using my Leica M kit less these days mainly because my eyes are just not up to it so it is difficult to justify holding onto everything I have bought over the past 25 years.) In my case these are all ZE lenses (as opposed to ZF lenses which are for Nikon bodies) signifying that they were made for the Canon DSLRs. This means that unlike the ones made for the Nikon DSLRs they do not have an aperture ring. Instead, the adapter for mounting these on a Sony body must contain electronics so the lens aperture can be operated through the relevant camera dial. I bought a Sigma MC-11 adapter which works fine in this regard and is relatively inexpensive compared to the top end electronic adapters, which however, support full auto focus on a wider range of Canon mounted lenses. The Sigma adapter is a little quirky in that respect but as all of my lenses are MF it is not an immediate issue.
This specific range of Zeiss glass is, as I said of the classical more simple and less corrected optical design, so tends to conform to that style of rendering and performance - the 85mm and the 35mm are in particular, still sharp but less than stellar sharp when shot wide open unlike many of the latest lens designs by either Zeiss or other marques. But all of them have what I suppose are classic Zeiss rendering characteristics - great contrast and beautiful colors. To top it off all of these lenses are built like tanks and are wholly manual focus - which I prefer. Big, heavy, all metal and glass and smooth as silk to operate. I have a fetish for big lenses but petite, slender............ well, maybe best not go there. What else can I say about these lenses though..........very nice indeed. 😛
Like many such purchases I cannot say I particularly needed these lenses, it was more an emotional and aesthetic choice. Story of my life!