First, you may want to fiddle the header of the map file a bit to adjust the origin and to adjust the range of densities.
Altering the origin is strictly optional, but the density range cannot be too high or mapman won't convert the file correctly.
 
 

for convenience choose origin which is -nx/2, -ny/2, -nz/2

densities in range of +/- 500 seem ok,  60,000 is NOT ok

setenv ODAT /opt/xray/o/data
copy access.o to working directory (contains cpu id's that are allowed to run O)
/opt/xray/o/bin/sg_ono621

./access.o

map_file xxx.map
map_obj xxx
map_param
map_draw

sam_atom_in        (read in pdb file)
mol  1jud          (create molecular object called 1jud)
centre_atom 1jud
paint_zone 1jud  101 1515 green
ca ; end

move_zone        (to move atomic coordinates by zone with updating coordinates)
move_obj            (to move obj without updating coordinates, e.g., map)

sk_obj  name
sk_type        (define type of sketch, e.g., cylinder)
sk_add        (do it)
sk_del?        (remove latest sk_add - like an undo command)

read alpha.o
read beta.o
sketch_setup
    cartoon
mol 1jud
yasspa 1jud alpha 0.5
yasspa 1jud beta 0.8
sketch_auto
 

First, alter header parameters in CCP4 file

altercell

keep a,b,c
alpha,beta,gamma -> 90.,90.,90.
space group -> 1

alternxyzst   (will alter origin of file)

for convenience choose origin which is -nx/2, -ny/2, -nz/2

prodadd    (will scale the map densities, which is required if they are VERY large)

densities in range of +/- 500 seem ok,  60,000 is NOT ok

/public/bin5/4d_mappage  (as of 3/99, other versions of mappage and mapman do not work, most likely due to irregular header data in CCP4 file from imgplt)
can specify prod/plus to obtain particular density range in O file, usually I specify "y" and 1.0 0.0 for prod, plus