Hi,
This occurs when executing the tkmedit command in order to perform white and grey matter edits. Clicking on zoom2 in order to enlarge the brain and then on Navigation Tool in order to drag the brain down.
On clicking on the display window, the brain disappears to the bottom right hand corner (out of view). Clicking on dragging from the bottom-right and dragging to the top-left drags the brain up but with the contrast becoming "white"/oversaturated. With repeated click-n-dragging up, this get progressively worse.
At times, while doing this, the following error is seen... "can't read "tViewPreset_None": no such variable"
In all instances, once the disappearance happens, the contrast it no longer usable.
Freesurfer version is 5.3.0, tkmedit stable5.
Any help would be great!
Regards, Chester