Synchronizing and delete?

Hi,

I know not why.... When I synchronize a folder, I get a lot of old pictures that I thought were delete.  I just want the new pictures to be synchronized and the old one to be deleted.  I am not seeing how I can do that when I choose synchronize my folder.

Is it possible to do this?  To choose synchronize my folder, then delete my old pictures and also import the new ones?

Thanks,