New Canon Patent applications filed for a set of RF mount lenses with electronically controlled Defocus Smoothing (DS).
Defocus Smoothing is a technology Canon first introduced with the RF 85mm f/1.2L DS lens. The featured Canon patent might suggest more DS lenses are on their way.
Canon patent application 2020-199390 (Japan) discusses optical formulas and methods for three prime lenses with DS:
- 135mm f/2
- 400mm f/4
- 50mm f/2.5
Example 1
- Focal length: 133.05
- F value: 2.06
- Half angle of view: 9.24
- Image height: 21.64
- Overall length: 170.39
- Back focus: 45.96
Example 2
- Focal length: 399.84
- F value: 4.00
- Half angle of view: 3.10
- Image height: 21.64
- Overall length: 298.46
- Back focus: 145.16
Example 3
- Focal length: 49.00
- F value: 2.50
- Half angle of view: 23.82
- Image height: 21.64
- Overall length: 68.15
- Back focus: 11.00
Here is a Video Review About What Defocus Smoothing is:
via asobinet