I am planning to have 10 albums up to 3 level subalbums, each album will have up to 300 MB images. We do not plan to advertise our site to a lot of users aprx 100 concurrent users. Will I experience problem with database? Or other load problem with Zen photo?
Where I can check Zenphoto load specifications?

My administrator advises me to create 10 subdomains and 10 related databases. Will it deacrease chance for overload? Or, do you think it's bad idea?

Thank you for reply.

300 MB is not that much nowaday. You sure won't need 10 subdomains and 10 databases as Zenphoto of course does not store image in the database. You find info here: http://www.zenphoto.org/2009/03/troubleshooting-zenphoto/#23

Your administrator seems not to be very knowledgeable. Your server will be running only one Web Server no matter how many domains you point at it. So increasing domains does nothing for performance.

Likewise, you are unlikely to be running more than one copy of the MySQL database application on the server no matter how many databases it is managing. In addition, managing lots of access to lots of data is what Databases are all about.

So, yes, this is a bad idea.