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= Control Points =

Control points are used in surface construction. Every subject has an associated ''control.dat'' file in their ''tmp'' directory; this is the list of control points, in Talairach space. Control points are also used for editing subject's with intensity normalization problems. For example, if the white matter surface does not fully extend to include all the white matter voxels. In this case, control points can be added to increase the intensity of the voxels around the problem area to increase the intensity to 110. To better understand these edits, [[FsTutorial/ControlPointsV6.0|click here to go to the control points tutorial]]. 

== Display Options ==

Control points appear as green dots in the Display Window. They can be turned off by choosing the ''Point Sets'' tab and unchecking ''control.dat''. 

== Editing ==

Control points can be edited by choosing '''File->Load Point Set''', a window will pop up, search for ''control.dat'' in the ''tmp'' directory as the file name and check ''Control Points'' and hit OK. 

To make a new control point, choose the '''Point Set Edit''' button, now you can click anywhere in the Display Window where you would like to add a control point. To delete a control point, '''Shift+Left Click''' on the control point you would like to delete. 

== Saving ==

To save edits you have made to the ''control.dat'' file, choose '''File->Save Point Set'''.