to the sensor. The distance between rear lens element and the sensor plane in R1 is about 2mm. Corner sharpness is said to be excellent. Lens seems to be 14-72 (optically). Classic lens designs always took benefit of the close placement of the lens to the film plane - this helped increasing resolution. If the limitations of the angle of incidence for WA lenses are not an issue with R1, we may see several nice things in a year or too.