LENS Kowa 8mm F1.4 For BMPCC M43, Faster Nicer Than SLR Magic F4 Laowa 7.5mm F2
Also you can see the SLR magic has a smaller rear due to being slower. Even compared to the laowa 7.5 f2, the kowa is much faster at F1.4. The lens covers a 2.7x crop on the bmpcc gh4 4k mode perfectly.