A new optical formula patent for a wide angle RF mount zoom has appeared. This one shows the formula for a couple of Canon RF 17-35mm f/4-5.6 designs.
The lenses in the two embodiments aren’t all that much smaller than an EF counterpart, and it looks like zooming is slightly external.
Canon RF 17-35mm f/4-5.6
Focal length: 17.50mm 27.00mm 33.95mm
F-number: 4.00 5.03 5.80
Half field angle: 51.03° 38.71° 32.51°
Image height: 21.64mm 21.64mm 21.64mm
Lens total length: 121.00mm 118.39mm 121.18mm
BF: 20.00mm 30.99mm 38.92mm
Canon RF 17-35mm f/4-5.6
Focal length: 17.50mm 27.00mm 33.95mm
F-number: 3.94 4.92 5.69
Half angle of view: 51.03° 38.71° 32.51°
Image height: 21.64mm 21.64mm 21.64mm
Total lens length: 122.00mm 119.11mm 121.87mm
BF: 20.00mm 31.62mm 40.07mm
Once all of the fast zooms ship this year, I think it’s safe to assume we’re going to see f/4 variants soon after.
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