[Tilecache] Configuring PIL for 4-bit colormap?

[Russell McOrmond]

   I notice when I use metaTile=yes that the PNG files I get are much 
larger than when metaTile=no.   I notice also that with metaTile=yes I get 
an 8-bit colormap, but with metaTile=no I get a 4-bit colourmap, which is 
likely the reason for the size difference.

   Is there a simple/etc way to configure tilecache and PIL to generate 
similar output for metaTile=yes as we get with metaTile=no?  I'd like the 
smaller files, but don't want to be sacrificing image quality to do so.

Thanks.

-- 
  Russell McOrmond, Internet Consultant: <http://www.flora.ca/>
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