15mm Lens???

So I went out shooting with my 25mm Zeiss, thing is nuts and now that I am starting to understand iso, focal lengths ect I think I need something a bit wider. I do own a 18-(35?) nikon lense, the good stuff (2Kish), would the zeiss distagon 15mm be a drastic improvement over this>

my 25mm I consider a very sharp lens, but the nikon is like recording to 2" tape. Just looking to start discussion about good lenses for having a large focal depth (large?).

I have a the bmcc ef, any recomendations?

So I went out shooting with my 25mm Zeiss, thing is nuts and now that I am starting to understand iso, focal lengths ect I think I need something a bit wider. I do own a 18-(35?) nikon lense, the good stuff (2Kish), would the zeiss distagon 15mm be a drastic improvement over this>

my 25mm I consider a very sharp lens, but the nikon is like recording to 2" tape. Just looking to start discussion about good lenses for having a large focal depth (large?).

I have a the bmcc ef, any recomendations?

For what I know, if you have the Zeiss ZE 25mm 2.0, it is a very sharp lens and renders a lot of detail. The 15mm f2.8 is as good or even sharper some may argue (focused at infinity that is). But if you have the Zeiss Ze 25mm f2.8, the 15mm is sharper!