[PyMOL] set transparency for selected elements of secondary structure

[James S. <jms...@gm...>]

Dear pymol users!

I am trying to set transparency based on the secondary structure using
pymol selection algebra

# set transparency to all helix and sheets but not loops
set cartoon_transparency, 0.5, ss H+S

which produce the following output
PyMOL>set cartoon_transparency, 0.5, ss H+S
 Setting: cartoon_transparency set for 144 atoms in object "0190_before_minim".

but actually do nothing in terms of visualization.

Could you suggest me how it would be possible to fix it?

Thanks in advance!