The available ratios are 3:2, 1:1, 4:3, 16:9, 65:24, 17:6, 3:4, 7:6 and 5:4. The attached camera JPEGs use 17:6 and 65:24. Resized previews with metadata removed; the original camera JPEGs are retained.
All nine ratios have been tested on this camera. JPEGs follow the selected framing, and the DNGs checked retain a 6000 × 4000 default image area and decode normally. I’ve also tested nine independently selectable film-simulation slots in a later build. Testing of the wider collection of looks is ongoing.
A custom shutdown image is another part of the project, but it still needs complete hardware validation. These results are specific to my GR IIIx HDF 1.60 setup, not a compatibility promise for all GR cameras.
I’m sharing this as the person working on the customization, not as an official Ricoh representative. Do you use wide ratios in everyday photography, or mostly crop afterwards? I’d be interested in exchanging practical experience with others who have wanted similar controls.