Note: this video was focused by two synchronized motors linearly. So the result is inaccurate.

Sharpness test for Leica Elimarit R 90mm f2.8 and Kowa 8-Z on BMPCC4k.

Conclusion

Sharp enough.

Test movie

1.8m

Metabones Speedbooster XL 0.64x
Leica Elmarit R 90mm f2.8 @2.8 Wide open
Kowa 8-z 2x anamorphic
(No Variable-Diopter)

BMPCC4k
fps: 24
Shutter: 180
ISO: 500
BRAW 4K DCI (4096 x 2160) 3:1
Crop factor: 1.22x ( = 1.9 x 0.64 )

Colored with Davinci Resolve 16 (contrast only)
No crop.

Youtube 2160p
Resolution: 4096 x 1716 DCI Scope 2.39
Format: QuickTime
Video Codec: H.264
Audio: Main 1 (Stereo)
Audio Codec: Linear PCM