[ccp4bb] making high res image in pymol

[A K]

Hi all,
I am trying to generate a high resolution figure of a molecule together
with its symmetry mates (250 A readius) for a poster. If I try to ray it,
the pymol session crashes (perhaps too many molecules are open). Using png
xxx.png, dpi=300 or dpi=600 command doesn't make any difference; the image
is still kind of low resolution for A0 or A1. Any idea how I can generate
this in pymol? (I am using the free version of pymol)
Thank you in advance,
Alex