Canon Patent Application: Canon RF 24-85mm, 24-70mm

This patent application appears to be for a Canon RF lens mount lens of 24-85mm in focal length with a constant aperture of F4.

One of the very necessary things for the RF mount, is a series of lighter weight and F4 zooms, not only the heavy and large exotic lenses.  This would be a welcome addition to the RF lens ecosystem.  Interestingly this lens also shows a significant ingress into the RF mount having a backfocus of 13.50mm where the RF mount has a distance of 20mm.  There is also two 24-70mm lens designs as well, however one is more unlikely because of the extreme mount ingress, having a back focus of only 7.69mm.

Focal Length 24.72  44.55 82.99
F-Number      4.12   4.12  4.12
Image height 21.64  21.64 21.64
BF           13.50  27.08 51.57

Focal Length 24.71  39.20 67.99
F-Number      4.12   4.12  4.12
Image height 21.64  21.64 21.64
BF            7.69  17.60 35.47

Focal Length 24.71  39.93 67.99
F-Number      4.12   4.12  4.12
Image height 21.64  21.64 21.64
BF           13.50  24.36 42.60 

US Patent Application 20180348481

Canon Patent Application: TS-E or medium format lenses Sigma ships the 70-200 2.8 DG OS HSM Sports lens