How do i use SLAVE on a flash canon speedlight 430Ex?
The little slave switch on your 430EX is only if you are triggering the 430EX from a 580EX, which can act as a master or as a slave. If the 580EX is in your hotshore, it will signal the 430EX when to fire and for how long. This uses both the 580 and 430 in a ettl (dedicated) mode. The device you pointed to is an optical slave. An optical slave will create a small charge when it senses another flash. That triggers the flash in it’s hotshoe. Note, this is different from the 580/430 scenario. This is not in a dedicated mode. You need to put your 430EX in Manual power mode and select a power level (like, Full, 1/2, 1/4 etc). You can use your on board flash to trigger the optical slave. This gets a little tricky – you should use your camera in Manual exposure mode (that’s different from using your flash in manual power mode). You cannot rely on your camera’s internal meter when you are using non-dedicated flash. This is fairly common in studios and with some people that are interested in of
