airport time capsule accounts

I'd like to set up two accounts, both with Read access to everything on the Time Capsule, but only the "Administrator" account having Write access.

Is this possible? I tried setting up Account access, but I apparently lost access to the existing files entirely, with each Account only being able to access their own respective folders...

(The purpose for this is that I hope to use it as basically a Server for images for several computers or tablets, but I don't want the "guest" viewers to be able to acc