To start Visions of past for imperials, Got to Corellia, Bela Vistal Shuttle B. Target Rich and speak to him. He'll give you the WP on Yavin for the NPC to talk to. Then go to the Yavin Labor outpost
and talk to the NPC who will give you a WP to the wreckage to search. At the wreckage site, find the "loose debris" and "deathstar debris". From these you will collect two items (one is an old lightsaber and the other is a decryptor)
Return to the NPC who will give you the prize!