By default the aspect ratio of images shown on list modules with artists or pages listed will be 4:3.
This can be overridden with some custom CSS added in site settings:
Site Settings > Design > Custom Styles
.module-page-image-box:after {
padding-bottom: 75%;
}
Use the following percentages for the listed aspect ratios:
1:1 | 100% |
4:3 | 75% |
3:2 | 66.67% |
16:9 | 56.25% |
2:1 | 50% |