In the final mission where you are in the area of the Death Star where all of the green lasers meet take the Graviton Generator up to its highest point You should then be able to see the Holocron It is on the platform just above the highest laser It is somewhat difficult to reach Use the Gravitron Generator to get as high as possible When you are higher than the platform that the Holocron is on press L1 Circle to get across

Once on the Death Star fight your way to the large focusing chamber with the two graviton lifts Fight the two AT-ST's at the bottom of the room then activate the lifts Take them to the very top of the room and kill any Imperials in your way At the top look above the laser focusing crystal and you should see a Jedi Holocron To get there you must jump on the beam above the laser channel If you can time it right you can get there by jumping from the top grav lift ring but this can take a while To make it easy stand on the top grav lift ring and pull one of the channel rings out of its place and put it between the Apprentice and the beam you need to get to Be sure to place it on the ground and then just let go or else the ring will break roll away or tip over Once in place jump onto the ring then onto the beam (be careful of the laser as one hit will kill you) then get the Holocron and equip the crystal!