Six Cu II lines and one of Cu I from a liquid nitrogen cooled hollow cathode lamp have been studied at high resolution (+or-3 fm). The six Cu II lines can be produced with a consistency of +or-10 fm under the following conditions: hollow cathode diameter 10 mm+or-1 mm, helium carrier gas at 400 Pa+or-50 Pa, discharge current of about 200 mA. These six lines are different types of transition and so many other Cu II lines in the vacuum ultraviolet should be obtainable with equally good consistency. The behaviour of these lines under different source conditions is discussed.