Here’s a crazy optical formula patent from Canon, an EF 40-800mm f/4.5-5.6 superzoom lens. The folks at Egami say it’s for a full frame DSLR and is an internal zoom lens.
Patent Publication No. 2016-128846 (Google Translated)
- Published 2016.7.14
- Filing date 2015.1.9
- Zoom ratio 19.42
- Focal length 41.09 92.80 152.20 225.00 797.99
- F-number 4.67 4.66 4.65 4.67 5.71
- Angle of view 27.79 13.13 8.10 5.50 1.55
- Image height 21.65
- Overall length of the lens 489.32
- BF 39.28
- Inner zoom
As pointed out on our forum, the patent contains 4 lens designs, two of them are for full frame, and two are for a PowerShot application. The likelihood of such a lens coming to fruition in full frame form? I’d say zero chance, but stranger things have happened.