If you wish to use a generic non-dedicated flash unit on the Canon EOS camera, you will first need to check the triggering voltage of the flash unit. The Canon Speedlite flash units triggering circuits is not more than 6 volts. Furthermore, the Canon EOS 1, A2/A2E, 10s, 630; Elan, RT and Rebel also operate with 6 volts as the maximum voltage going through their triggering circuits. As such, you must make sure the generic flash unit also uses no more than 6 volts for their trigger.
Those triggers which use more than 6 volts can damage the electrical circuitry of the camera. The connecting wires, the X-Sync contact point and the shutters are most prone to damages. The damage might not be obvious but will happen gradually over time. Beside from the likelihood of circuitry damages, electro magnetic noises generated by the high voltages will cause interference with the Camera operation. The metering system, aperture settings and shutter speed are just some of the possible effects of electro-magnetic noise on the circuit of the camera. Which function will be affected will depend ultimately on the circuits which is interfered with by the electromagnetic noise.
Testing the voltages of the flash triggering circuit is a simple task. Just use a voltmeter which is available at any Radio Shack stores. Connect the positive lead to the positive point of Sync Cord. The Negative lead should be connected to the ground of the Sync cord. With shoe mounted flash, just connect the positive lead to the center point of the mount. The negative lead has to be connected to the grounding point of the camera located at the side of the lock nut. Voltmeters have different setting which you can use. If you are unaware of the voltage of the Flash unit, just use the highest setting on the voltmeter than work your way downwards.
You can actually fire a Studio Flash unit safely without a Sync cord. To do so, just use a Speedlite 420EZ or 430EZ at 1/32 power setting under manual flash mode. Make sure the optical slave trigger is turned on before firing. What you are actually doing is utilizing the bounce features of the Speedlite 420EZ or 430EZ to divert the flash light to the optical slave trigger. On the other hand, you can use slave triggers which are linked by radio signals to fire the Studio flash. These radio transmitters and receivers, which are connected to the Camera's PC contact and the Flash power packs, are manufactured by companies like Lindahl and Quantum Instruments.
If the Studio Flash is not firing through the EOS Camera, you should check the following listed below:
(1) That the third party PC socket adapter do not have a metal shoes. This will result in a short circuit in the trigger circuit. The remedy is use Canon PC socket adapter which is made from plastic.
(2) Ensure that the Polarities of the Flash Units are correct with the camera X-Sync contact. This is usually caused by a diode connected to the Camera's X-Sync contact to protect the camera internal flash. The solution is to reverse the polarity of the sync cord.
3. If after having tired these two suggested solution and the Flash still wont fire, then just adopt the method described above to fire the Flash without the use of the Sync cord. - 16752
Those triggers which use more than 6 volts can damage the electrical circuitry of the camera. The connecting wires, the X-Sync contact point and the shutters are most prone to damages. The damage might not be obvious but will happen gradually over time. Beside from the likelihood of circuitry damages, electro magnetic noises generated by the high voltages will cause interference with the Camera operation. The metering system, aperture settings and shutter speed are just some of the possible effects of electro-magnetic noise on the circuit of the camera. Which function will be affected will depend ultimately on the circuits which is interfered with by the electromagnetic noise.
Testing the voltages of the flash triggering circuit is a simple task. Just use a voltmeter which is available at any Radio Shack stores. Connect the positive lead to the positive point of Sync Cord. The Negative lead should be connected to the ground of the Sync cord. With shoe mounted flash, just connect the positive lead to the center point of the mount. The negative lead has to be connected to the grounding point of the camera located at the side of the lock nut. Voltmeters have different setting which you can use. If you are unaware of the voltage of the Flash unit, just use the highest setting on the voltmeter than work your way downwards.
You can actually fire a Studio Flash unit safely without a Sync cord. To do so, just use a Speedlite 420EZ or 430EZ at 1/32 power setting under manual flash mode. Make sure the optical slave trigger is turned on before firing. What you are actually doing is utilizing the bounce features of the Speedlite 420EZ or 430EZ to divert the flash light to the optical slave trigger. On the other hand, you can use slave triggers which are linked by radio signals to fire the Studio flash. These radio transmitters and receivers, which are connected to the Camera's PC contact and the Flash power packs, are manufactured by companies like Lindahl and Quantum Instruments.
If the Studio Flash is not firing through the EOS Camera, you should check the following listed below:
(1) That the third party PC socket adapter do not have a metal shoes. This will result in a short circuit in the trigger circuit. The remedy is use Canon PC socket adapter which is made from plastic.
(2) Ensure that the Polarities of the Flash Units are correct with the camera X-Sync contact. This is usually caused by a diode connected to the Camera's X-Sync contact to protect the camera internal flash. The solution is to reverse the polarity of the sync cord.
3. If after having tired these two suggested solution and the Flash still wont fire, then just adopt the method described above to fire the Flash without the use of the Sync cord. - 16752
About the Author:
Tim Harris is a canon camera enthusiast. For tips on choosing and buying cameras, do check out Canon OS Camera website. Camera 40D Digital Rebel XTI 3D Blog
