PDB: Modifiying atom radius via pdb-file

[Markus Franke]

Hello,

i have a pdb-file and i want to change the radius of several atoms.
i read something about the 3D's COLOR record extensions but there was no
example. Has anybody an idea how i could set the atom radius in a 
pdb-file so that rasmol will show the modified pdb-file correct?
Examples are welcome. :-)

Thanx for help
Markus
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