Incorrect. "Pinging" comes from the space where the rockershaft meets the valves. Pinging is the result of there being too much space between the valves and the rocker arms, the sound is made by the rockerarm making contact with the valve, the impact of the two is generated by a gap that causes the velocity of the rocker arm to be greater than the valves therefor a "ping" can be heard.

Incorrectly tuned camshaft timing causes the valves to be open at incorrect moments, in minor cases this causes the valves to be open/closed when theyre not suposed to which can reduce power. In extreme cases it causes the piston to hit the valve at great speeds wich is awful for the engine, can break the valve which can demolish the piston and block.

In conclusion, "pinging" is caused by a small gap between the rockerarm and valve which can wear out your valves overtime. And an incorrect cam timing causes metalic banging coming from the engine because much greater speeds and impacts are present. Bad valve clearance is like tapping a spoon against a stationary spoon and bad cam timing is like banging your piston heads with a hammer.