The problem is your "vop new" map is not centered on the atomic model. While you could try to center it so it covers the atomic model I think it is easier to just crop the the non-cube map produced by molmap to be a cube of size 256 by 256 by 256. For example
volume #2 region 26,24,14,281,279,269 showOutline true
save box.mrc model #2
The region option of the volume command lists the grid bounds imin,jmin,kmin,imax,jmax,kmax which I chose to make each dimension 256 grid points. You may need to use the molmap command edgePadding option to get a bigger molmap box around the structure. Instead of figuring out what numbers to type in the region command you can just use the Crop mouse mode in the Right Mouse toolbar and drag the faces of the molmap volume until you get it to a size of 256 cubed (size shown in the volume viewer panel). Yet another trick to get the cube map would be to use the "volume boxes" command
for instance in my example, I place a marker at the center of the molmap using the Toolbar Marker tab, click the Center mode, and right click the map to place a marker. That logs this command
marker #3 position 133.9,134,133.1 color yellow radius 1
Then to extract a cube box of size 256 centered at that marker
volume boxes #2 centers #3 isize 256
That didn't quite work giving a box size 256 x 256 x 247 because my molmap box was not big enough to cover so I would go back and use the molmap edgePadding option to have molmap create a bigger box around the atomic model.
Tom
On Aug 22, 2024, at 12:24 PM, Grigory Mechetin, Ph.D. via ChimeraX-users <chimerax-users@cgl.ucsf.edu> wrote: