This article explains where photos you upload to your group are stored, and who can access them depending on the group's settings.

Any photos that you upload to Yahoo! Groups are stored on the Yahoo! Groups website. Who can view the albums depends on the settings of your group. If you are part of a public group, anyone can view the photos. If you are part of a closed group, only group members will be able to see the photos.

Note: If you select “This album is personal” when creating an album, other group members will still be able to see the photos in the album – they just won’t be able to edit them.