Skip to content

Canon Patent Application For Speedbooster-like Focal Reducer

Focal Reducer

Hi Lows Note spotted a Canon patent application 2019-003074 that describes a focal reducer.

A focal reducer does the opposite of a teleconverter, reduces the focal length and increases the lens aperture. You likely know that from the Metabone Speedboosters.

Specification and lens arrangement of master lens 1 (18-55mm, F2.8)
Zoom ratio: 3.05
Focal length: 17.50 – 53.35 mm
F number: 2.80 – 2.80
Half angle of view: 36.65 – 13.71 
Image height: 13.02 – 13.02 mm
Lens length: 148.81 – 172.70 mm
Back focus: 35.51 – 40.31 mm

Specification and lens arrangement of master lens 1 with reducer 1
Focal length: 11.36 mm
F number: 1.82
Half angle of view: 36.67 
Image height: 8.46 mm
Lens length: 142.26 mm
Back focus: 2.00 mm

Specification and lens arrangement of master lens 2 (34mm, F1.4)
Focal length: 34.20 mm
F number: 1.45
Half angle of view: 32.32 
Image height: 21.64 mm
Lens length: 129.16 mm
Back focus: 39.35 mm

Specification and lens arrangement of master lens 2 with reducer 5
Focal length: 23.92 mm
F number: 1.02
Half angle of view: 32.33 
Image height: 15.14 mm
Lens length: 125.59 mm
Back focus: 2.00 mm

Back To Top

Notice

This website or its third-party tools use cookies, which are necessary to its functioning and required to achieve the purposes illustrated in the cookie policy. If you want to know more or withdraw your consent to all or some of the cookies, please refer to the cookie policy.
By closing this banner you agree to the use of cookies.