By John Siskin
This blog is about getting your strobes to work together as a team, I recently wrote about how to trigger one strobe from the camera, now we have to get the rest of the lights to go off. There is a slave unit that is particularly handy for this purpose: an optical slave. These trigger a strobe when they are hit by another strobe. I use a lot of these to trigger additional strobes on a shoot. Slaves are generally a small package of electronics encased in solid plastic. They have different connectors for different strobes: pc, household, 1/4inch headphone style and hot shoe.
 Optical Slaves 9 slaves including PC plugs, household plugs, hotshoe connectors and the large headphone style plugs. These units have very different sensitivities. This is the grope of slaves I usually take with me on location. © John H. Siskin All rights reserved |
The big problem is that slaves don’t always work. Several reasons of this, first the slave may not “see” enough light. The simple way to deal with this is connect the slave to a sync cord and move the slave closer to another light. You can do this with a radio receiver also. You can also get slaves that are more sensitive; of course they cost more. Another problem is that slaves and power packs, particularly packs that use the household connector type sync, need the plug put into the pack in a certain direction. The answer to this is simple: take the slave out turn it 180º and plug it back in. Sometimes a slave with a household connector will keep triggering, this means that the slave needs to be plugged into the pack in the other direction. Both problems with the household connector are a result of polarization in the sync circuit and the slave. Then there are slaves that stop working. I don’t know why they do this but I check all my slaves every few months to find out if they still work. Lastly there are situations when the strobe goes off when you don’t want it to. If someone else uses a strobe it will trigger your optical slave, this is why optical slaves are not good at weddings. Sometimes other things will trigger slaves. I once had a problem with a flashing light on top of a forklift!
 Covered porch, pool and landscape © John H. Siskin All rights reserved |
Optical slaves may be a little annoying but a handful of them will make impossible shots doable! In this next shot I have 9 lights! I couldn’t have done it without optical slaves.
Have Fun!
John
Comments