Batch-set aperture

My images have no aperture because the lens is manual. I would like to set default aperture to f11 if no Exif is found, but I can't do that anywhere.
Feature request for having a "Default aperture" box in Edit > Settings > Images, as well as being able to set an aperture for all selected images in the "Image Properties" window
Feature request for having a "Default aperture" box in Edit > Settings > Images, as well as being able to set an aperture for all selected images in the "Image Properties" window