- Go to the Shape tool tab or long-press the Crop tool in the Cursor toolbar.
- Select Add aspect ratio... from the list.
N.B. As of Capture One 22 (15.3) your Aspect Ratio will be remembered on a per-variant basis. It is no longer a 'global' setting.
- Add a name and the ratio dimensions needed in the dialog box. Press OK.
- The new ratio will appear in the Ratio drop-down menu.