A:AnswerThe SAL55300 is not compatible with a DSLR-A390, to see compatible DT lenses you may refer to the link below.
http://esupport.sony.com/US/perl/support-info.pl?template=&info_id=632#L1
A:AnswerHi Edward, the SAL55300 will require an LAEA adapter. If you do not want to use an adapter, other optional lenses comparable to that model would be the SEL55210 or SEL70300. Best regards, Zander