thanks, the capacitor idea worked..... kinda, as it is my test LED is on constantly, but as soon as i touch the negative leg of the capacitor it starts flashing exactly how i want, if, whilst holding the negative leg i touch any other part of the circuit the light goes out completly.
does this mean that i have the capacitor the wrong way round? (the negative leg of the capacitor is fed by the 5v from the LDR and the positive leg is going to the transistor base)
or does it mean that the capacitor is not big/small enough? (electrolitical 100uf 25v cap)
thanks everyone for your help, this is so close to working and then i can move on to the micro proccessor programing