Ricoh has a patent (P2018-224783) for what appears to be a new Pentax DFA 70-300mm f/4.5-5.6 SR or similar:
- Focal length: 72.2 135.0 193.2
- F value: 4.43 4.88 53.4
- Back focus: 38.3185 49.5751 57.6036
- Seven different lens designs are described in the patent with apertures ranging between:
- f/4.43 and f/4.63 at the shortest focal distance
- f/4.88 and f/5.19 at the focal distance of 135mm
- f/5.34 and f/5.74 at the longest focal distance
Via Pentaxforums, Digicame-info
