[Chimera-users] density maps & sub-region selection.

Hi, I am trying to select subregions in two density maps using the subregion selection option in the volume viewer. When selecting the same subregion different sub-volumes in the two maps are selected (there is a displacement between the ROIs along the Z axis) even though the two maps are aligned to each other (or appear to be aligned in the display window). Both maps are in the MRC format and both have a voxel size of 2A/pix. ? Ideally what I want to do is to select equivalent regions of the two maps and then save them as new density maps. How can I best do this? Thanks Hernando. UCSF Chimera version alpha 1.7 (build 36659) on Windows 7 64b