Can we take pictures Of rehearsals?

I'm a member of a Community Theater current rehearsing the musical "Oliver". Of course we have a large cast which includes children and families. The question came up regarding the legality of anyone taking rehearsal and dress reshearsal pictures and cast members posting them on there individual facebook pages. Is this ok? Can pictures be taken of cast members during rehearsals in or out of costume and publicly posted by cast members? and or can they even be taken and posted on the Theater company's private cast member facebook page? And what about video recording of rehearsals? 

Your help with any information pertaining to our questions would be greatly appreciated, Our Production and its process is very important to us.

Thanks Again,

Ochies5