Yes, the software that SMC uses resizes files...there is an upper limit and I forget what it is, but with reason, it does the job. The single thing that folks need to pay attention to is that uploading directly from "devices" (phones and tablets) sometimes results in photo orientation issues because of how mobile devices store them...the SMC software doesn't "read" the metadata properly...which is why bringing them into some other application and resaving them "fixes" that issue.