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Center Your Sample

1. Turn on continuous imaging.
2. Rotate your sample in 30 degree increments. Find the angle where your sample reaches the left-most position on the screen. Mark the left edge of your sample on the screen with a post-it note.
3. Rotate the sample 180 degrees. Mark the right edge of your sample with a second post-it note.
4. From the "BL Control Main" labview window (which you can open by double-clicking the desktop icon), open the motors subwindow (select the motors->display motor window menu). Choose the "Centering Motor" from the list of motors. The motor should start from the position where it is at the reverse limit. You can usually move it at least 2 mm forward before it is close to contacting the sample stage, so move it forward by 2 mm. Then move it in increments of about 0.1 mm, watching the image on the monitor as you go. Your task is to center the sample between the two post-its.
5. BEFORE YOU ROTATE THE SAMPLE again, retract the centering motor until it hits the reverse limit switch.
6. Repeat if you didn't get it perfect the first time.