A considerable surge in log prices has been recently noticed in Central/West Africa. This is the result of producers trying to pass on a new 15% increase in export duties on logs imposed by the government of Cameroon.    The move by Central/West African producers to raise asking prices by the full 15% export duty is perhaps optimistic. Only over the coming weeks will a clear picture emerge of how buyers are responding. The increased prices, say producers, applies to all markets.    Previous discussions had been on an export quota system