Canon Patent Application: Canon RF 15-35mm F4L

This is a lens I'm certainly waiting for.  We have seen rumors that an ultra wide F4 lens is coming out in 2021.  Would I get one of these.  I'm waiting for this before jumping into the RF mount to be honest. 

Canon states;

The present invention is compact, and it is an object of various aberrations including chromatic aberration to provide a well corrected zoom lens.

Make it happen Canon ;)

The 15-45mm lens design looks more realistic with a 19mm back focus distance than the 16-35mm F4 lens with the rather short back focus distance.

Canon RF 15-35mm F4L

Focus distance          15.45  24.00  33.95
F Number                 4.12   4.12   4.12
Half angle of view (°)  54.47  42.03  32.51
Image height            21.64  21.64  21.64
Lens total length      150.01 141.11 140.23
BF                      19.25  31.83  46.78

Canon RF 16-35mm F4L

Focal length            16.48  24.00  33.95
F number                 4.12   4.12   4.12
Half angle of view (° ) 52.70  42.03  32.51
Image height            21.64  21.64  21.64
Lens total length      132.09 128.84 134.21
BF                      10.35  19.54  33.20

Japan Patent Application 2020-190636