Since iPhoto can only work with a single library at a time, you need to decide in advance how you're going to divide up your images.
Ebe ọ bụ na iPhoto nwere ike na-arụ ọrụ na otu ọbá akwụkwọ n'otu oge, ị ga-ebu ụzọ kpebie otú ị ga-esi kewaa ihe oyiyi gị.