as interesting as the Harblei cam is, it is not unique.
I have been using the TrueWide from Kapture group for almost a year with the ONLY Leica R mount they ever did!
attached.
I used with P45+ (better with crop factor) now P65+ (vignetting, but sill more than 40MP center)
see the setup and image (cropped)
that is with Leica R Modular 800mm 200 ft away
HOWEVER, and it is a BIG however, the TrueWide has a copal shutter max 1/125
hence the massive optical bench (with 28" RRS camera bar!)
[and yes, color balance offf didnt convert from PhotoProRGB to sRGB :-(
BTW do click to see the large image. detail is impressive
Imaging a 40MP Leica R... better than an R10
and yes, I am considering the Hcam with 1/4000!
Victor