[ismaelg]

Hi,

We are aware that older flashes with high voltage triggers can damage a DSLR if mounted on the hotshoe. How about using a PC sync cord? I would guess it is the same thing but I'm curious......

Thanks,

[mtansley]

I'm guessing that the two connections join up at the same place in the electronics and would be subject to the same problems.

[keithlester]

You are correct, however the correct voltage will only be read by a high-impedance voltmeter. A cheap, low-impedance multi-meter will give a false low reading which may lull you into thinking the voltage is in spec for your camera, when it is not. Hope this helps..

[grhazelton]

You are correct, however the correct voltage will only be read by a high-impedance voltmeter. A cheap, low-impedance multi-meter will give a false low reading which may lull you into thinking the voltage is in spec for your camera, when it is not. Hope this helps..

This is probably why a digital VOM is recommended. Forturnately they're cheap - perhaps $20 at Lowe's or Home Despot.

[sterretje]

The first series of Metz 45CT-1 is not digital safe (according tot he Metz website); and those only have a PC socket. So I guess that it does not matter.

As an electronic engineer, I would indeed simply put the in parallel so there would be no difference between the hotshoe and the PC socket.

PS I wonder where you got the specific reference to the hotshoe from; never seen that specifically.

[demp10]

How about using a PC sync cord? I would guess it is the same thing

Not necessarily. I read that the PC port can handle higher voltages but Pentax never specified how high. If they used a simple SCR to isolate the port, they should be able to handle up to 400V easily.

The hot shoe is another story since it has all the other connections that by nature are low voltage.

The best insurance policy is to get a pair or radio triggers. As an added bonus you get very flexible off camera flash options. The Cactus V, that I use, even has an isolated hot shoe on top of the transmitter. You can mount the transmitter on the hot shoe, mount a high voltage flash on the top of the transmitter and you are good to go.

[Wheatfield]

FWIW, I use an older Metz 60CT-2 flash with my cameras, and as well I have used them plugged into a really old Norman p200D power pack with no ill effect. To my mind, if the PC socket can't handle the high trigger voltage that some studio lights put out, they have no business putting a PC socket on the camera.
I don't know what the owners manual says about this.

[mtansley]

FWIW, I use an older Metz 60CT-2 flash with my cameras, and as well I have used them plugged into a really old Norman p200D power pack with no ill effect.

That old Metz triggers at around 200-250 volts if it's anything like a couple of 45 CT-1s I have although I cheat and use a safe-sync on the hotshoe.

[demp10]

There is a YouTube video from a Pentax Product Manager, describing the K20D back in Jan 2008. At the end of the clip (about 6:50), he states that there is a special circuit in the PC socket to protect from high voltages. He does not say though, how high.

Here is the link

You Tube

You Tube

[lordofthestrings]

Not necessarily. I read that the PC port can handle higher voltages but Pentax never specified how high. If they used a simple SCR to isolate the port, they should be able to handle up to 400V easily.

The hot shoe is another story since it has all the other connections that by nature are low voltage.

The best insurance policy is to get a pair or radio triggers. As an added bonus you get very flexible off camera flash options. The Cactus V, that I use, even has an isolated hot shoe on top of the transmitter. You can mount the transmitter on the hot shoe, mount a high voltage flash on the top of the transmitter and you are good to go.

Hi, I have the V4s and I use them with my old flash (high voltage National PE2057) off camera and "onboard" with a simple bracket, wireless in both cases. The flash has also a sync port; I wonder if I can use the sync cable bundled with the Cactus to fire the flash without voltage issues (when "onboard" on the bracket, assuming it is more reliable than the wireless mode). Do you think the flash would damage the Cactus transmitter? Because officially the Cactus receiver can handle high voltage flashes attached to its hotshoe, but what about the transmitter sync port? Thank you.

[maxfield_photo]

In the K20d's manual it states that the PC socket is shielded against high voltages, but it does not say how high "high" is. The figure that I've read is 31V, above that I'd say you are taking your chances. I've used an analog version of the Metz 45CL-4 on my K20d via the PC socket for years now with no adverse effects. It triggers at around 17V which is enough to fry a digital Canon or Nikon.

[demp10]

Hi, I have the V4s and I use them with my old flash (high voltage National PE2057) off camera and "onboard" with a simple bracket, wireless in both cases. The flash has also a sync port; I wonder if I can use the sync cable bundled with the Cactus to fire the flash without voltage issues (when "onboard" on the bracket, assuming it is more reliable than the wireless mode). Do you think the flash would damage the Cactus transmitter? Because officially the Cactus receiver can handle high voltage flashes attached to its hot shoe, but what about the transmitter sync port? Thank you.

I am not familiar with the V4s since I have only V5s, so my observations are for that system. The V5s are transceivers and you can set them in transmit or receive mode with a switch. My understanding is that in receiver mode both the top female hot shoe and the PC socket (actually a 3.5mm stereo socket) can trigger a high voltage flash. I used that mode in both configurations with my Vivitar 283 that has over 200V.

In transmitter mode, the top female shoe can trigger high voltage flashes safely working as an isolation port. The PC socket and the male hot shoe are used to triggered the unit and either one should be connected to the camera; either mount the unit to the hot shoe of the camera (and optionally a flash on top of it) or use a PC cord from the camera to the unit (you can still mount a flash on the trigger and fire it).



You may want to consider the following setup to be safe.

• Mount the flash on the transmitter and measure the voltage at the PC terminals.
• The measured voltage should be very low (less than 6 V). DO NOT use it if it is high.
• If you measure a low voltage on the PC terminal of the transmitter with the flash on top and ON, then use a PC cord from the camera to the trigger.
• Attach the trigger-flash unit to a bracket and you are good to go.
• Essentially you are using the transmitter as an isolation port.

[lordofthestrings]

I am not familiar with the V4s since I have only V5s, so my observations are for that system. The V5s are transceivers and you can set them in transmit or receive mode with a switch. My understanding is that in receiver mode both the top female hot shoe and the PC socket (actually a 3.5mm stereo socket) can trigger a high voltage flash. I used that mode in both configurations with my Vivitar 283 that has over 200V.

In transmitter mode, the top female shoe can trigger high voltage flashes safely working as an isolation port. The PC socket and the male hot shoe are used to triggered the unit and either one should be connected to the camera; either mount the unit to the hot shoe of the camera (and optionally a flash on top of it) or use a PC cord from the camera to the unit (you can still mount a flash on the trigger and fire it).



You may want to consider the following setup to be safe.

• Mount the flash on the transmitter and measure the voltage at the PC terminals.
• The measured voltage should be very low (less than 6 V). DO NOT use it if it is high.
• If you measure a low voltage on the PC terminal of the transmitter with the flash on top and ON, then use a PC cord from the camera to the trigger.
• Attach the trigger-flash unit to a bracket and you are good to go.
• Essentially you are using the transmitter as an isolation port.

Thank you. Now I see what's the difference between V4 and V5... I didn't understand it when I compared them at first... I chose to go slightly cheaper but the V5 are really different (transceivers) acting eventually like a safe-sync too. I guess it's better safe than sorry and continue firing my flashgun in wireless mode... ;-)

[Anvh]

The international standard says 24volt for the trigger voltage with the hotshoe and Pentax have said they are confirm to the standard.