In a patent uncovered by Canon News, it appears Canon is continuing the development of EF telephoto lenses. This patent is related to the focusing speed of the lenses as well as the reduction in aberrations.
Canon EF 300mm f/2.8L IS USM
Focal length: 294.00mm
F number: 2.91
Half angle of view: 4.21°
Image height: 21.64mm
Total lens length: 276.40mm
BF: 65.35mm
Canon EF 400mm f/2.8L IS USM
Focal Length: 392.00mm
F number: 2.90
Half angle of view: 3.16°
Image height: 21.64mm
Total lens length: 371.25mm
BF: 69.92mm
Canon EF 500mm f/4L IS USM
Focal Length: 490.00mm
F-number: 4.12
Half angle of view: 2.53°
Image height: 21.64mm
Total lens length: 410.77mm
BF: 66.03mm
Canon EF 600mm f/4L IS USM
Focal length: 588.00mm
F-number: 4.12
Half angle: 2.11°
Image height: 21.64mm
Total lens length: 474.78mm
BF: 80.59mm
Canon EF 800mm f/5.6L IS...
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