| Joined: | Thu Apr 12th, 2012 |
| Location: | Denham, United Kingdom |
| Posts: | 293 |
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GeoffR wrote:The flash trigger voltage is nothing to do with the supply voltage for the camera electronics. Flash trigger voltage is determined by the design of the flashgun, older flashguns trigger the flash tube supply directly, newer flashguns trigger that electronically via an isolator. The reason for camera manufacturers specifying a low voltage trigger is that there are accessory contacts in the hot shoe and putting 300V on those would fry the electronics (they are for TTL flash control etc.). This can happen when a flashgun is mounted in a charged condition, always switch off your flash before connecting it to the camera.
All batteries have a drop in terminal voltage when on load, Li-ions are no different. I suspect that the EN-EL4 is quoted open circuit and the EN-EL18 on load. The difference is 2.7% well within an acceptable voltage range for the vast majority of electronic devices.
A voltage regulator may well be incorporated but the motors won't be adversely affected by changes in voltage. With a battery voltage around 11 Volts, and I suspect most of the electronics runs at 5 or 6 Volts, regulation would be required to provide the correct voltage to the electronics.
The Electronics running on a Particular Lower Voltage , would that not be Indicated by the recommended Flash-Voltage , was it 6 Volts and No-more that Nikon specifies for their Digital camera`s , or Fried electronics would be the result...therefore rendering elder Flashes Obsolete.
Someone told me , that there is a Difference between Hot shoe output vs. Flash-nipple on a Digital camera, the flas-nipple being an El.magnetic switch capable of handling several Hundred volts..Not willing to put his sayings to the test , Risking a camera-funeral...
Could it be true nonetheless ??
There is generally only one switch on the shutter with the PC socket and Hot shoe in parallel but there may also be isolators in the circuit so that an excessive voltage takes out the isolator not the shutter actuated switch.