Flash trigger voltage - PENTAX official answer

ma318 · 01-24-2010, 12:01 PM

Originally posted by ryan s

Reverse polarity = most flashes use the bottom, center pin as the +, and the little metal pieces inside the "shoe slot" are the ground. Some are the opposite and use the center pin as ground.

And on this issue, I'll say...come on people. I know old flashes are cheap/free...either sell them and buy one of the boatloads of good flashes for under $100 (Nikon SB series...love my 24)...buy a Safe Sync...buy a hotshoe -> PC adapter...buy a wireless flash solution...something.

Don't risk a mutli-hundred dollar camera with a free flash. The worst that could happen is you kiss your flash circuits goodbye, and we'll probably laugh and say "told you so." Wait...that's not very good

I think your suggestion is appropriate for majority of the people out there. But for the sake of the new camera users who do not know any better and just happen to have one of those old flashes sitting around and for the sake of the real tinkerers who like to do weird and creative things with their old flashes, Pentax should publish the maximum trigger voltage and current and write a clear caution statement regarding older flash in the manual. This should actually help them sell more cameras to those tinkerers and prevent, to a certain degree, the uninformed newbies from blowing up their camera.

Note: I think most hotshoe to PC adapter may not provide high voltage protection. If your camera has a build-in PC port, then the PC port is protected from "high" voltage. But this protection does not extend to its hotshoe.

Last edited by ma318; 01-24-2010 at 08:50 PM.

ryan s · 01-25-2010, 01:13 PM

Originally posted by ma318

I think your suggestion is appropriate for majority of the people out there. But for the sake of the new camera users who do not know any better and just happen to have one of those old flashes sitting around and for the sake of the real tinkerers who like to do weird and creative things with their old flashes, Pentax should publish the maximum trigger voltage and current and write a clear caution statement regarding older flash in the manual. This should actually help them sell more cameras to those tinkerers and prevent, to a certain degree, the uninformed newbies from blowing up their camera.

Note: I think most hotshoe to PC adapter may not provide high voltage protection. If your camera has a build-in PC port, then the PC port is protected from "high" voltage. But this protection does not extend to its hotshoe.

They should do that, although I bet they'll get people saying "the manual said xxx, and mine was xxx...but something's wrong"

Then you get into variances of multimeters and all that. For example, my "average" meter that most folks have doesn't show an absolute 0 reading for impedance...more like 1.5 Ohms. I'd have to wonder how far it's off once the voltage starts going to 400+.

I have no idea if the hotshoe -> PC provides a safe connection...it's been a while since I read about them, and I use wireless triggers anyway.

ma318 · 01-25-2010, 01:37 PM

The reality is that without the maximum voltage stated in the manual anything, other than a Pentax flash, mounted on the hotshoe is "potentially" not safe. The radio triggers are definitely "safer" but without the the voltage stated in the manual, Pentax does not have to fix any damage unless you are using a Pentax flash.

wildlifephotog · 01-25-2010, 03:14 PM

Pentax is ISO 10330:2002 compliant. That sets a 25 volt standard on the flash voltage.
If you think printing anything in the manual would help, I doubt it. You know how many times folks have to be told RTFM?
Good tinkers would check out the info before doing anything possibly bad for the camera.
Any Pentax flash will work. And all the new top 3rd party flashes will work if marked for Pentax. Other than that, you have to play on your own dime.

ma318 · 01-25-2010, 03:42 PM

Wildlifephotog, you sound like you know what you talking about. That's good enough for me. Thanks for the info.

justDIY · 01-25-2010, 04:22 PM

The manual states to use a Pentax flash with my Pentax camera ... would that include the Pentax Takumar AF14 Flash, from twenty some odd years ago?

I've got one coming in the mail, for basically the cost of shipping. I'll be testing it with a multimeter before mounting it up.

ma318 · 01-25-2010, 04:49 PM

I don't have such a flash so I don't know for sure. Maybe someone who has one will let you know.

If you are following the instructions exactly in your manual then you should be in good shape.

Since it is a used flash and you don't really know the condition it is in, you should always put a fresh set of new batteries in and check its trigger voltage to make sure it is safe. It is a very easy thing to do. That will give you the peace of mind.

Last edited by ma318; 01-25-2010 at 05:01 PM.

ryan s · 01-25-2010, 08:24 PM

Originally posted by justDIY

The manual states to use a Pentax flash with my Pentax camera ... would that include the Pentax Takumar AF14 Flash, from twenty some odd years ago?

I've got one coming in the mail, for basically the cost of shipping. I'll be testing it with a multimeter before mounting it up.

I had an AF16 (pretty sure it was) and it tested low. Definitely check yours out before mounting since it's not listed here Photo Strobe Trigger Voltages

ChopperCharles · 11-22-2013, 07:14 AM

What is considered "high" voltage? I have a Vivitar Auto Thyristor 225 that I use on my Q, and it has a 35v trigger voltage.

Charles.

GibbyTheMole · 11-22-2013, 09:11 AM

Originally posted by ChopperCharles

What is considered "high" voltage? I have a Vivitar Auto Thyristor 225 that I use on my Q, and it has a 35v trigger voltage.

Charles.

That's too high from what I've read. 24 volts is considered the maximum "safe" voltage for any Pentax DSLR, and personally, I like to stick to 12 volts or less just to be on the safe side. I'm not sure if the Q is the same as their DSLRs, but I'd guess it probably is. I'd stop using that flash immediately, or buy a Wein Safe Sync if you really want to keep using it.

I use Sunpak 422D flashes with my Pentax K-x bodies and the Q. It's a great and cheap flash unit with a trigger voltage of around 6 volts.

LXNights · 12-30-2014, 11:51 PM

I have a Vivitar 285 and Sunpak 622. DO you think those are safe to use with current Pentax cameras like the K-7, K-5, K-50, K-30, K-3, etc.?

MPrince · 12-31-2014, 03:54 AM

Originally posted by LXNights

I have a Vivitar 285 and Sunpak 622. DO you think those are safe to use with current Pentax cameras like the K-7, K-5, K-50, K-30, K-3, etc.?

The only sure way to know is to check the trigger voltage. Buy or borrow a digital multimeter (you can buy one for under $10), then do a google search for how to check the trigger voltage. It's pretty easy, and will give you peace of mind.

wildlifephotog · 12-31-2014, 04:37 AM

LXNights:
The 622 is safe. The 285 is not.
The 285 is 350 volts and the 285HV is 12 volts.

The damage probably won't happen on the first use. It will likely happen from continued use and that is what destroys the electrical components.
Using old high voltage flashes is false economy. They were built and used when actual metal contacts handled the voltage in the camera. The components used in modern electronic cameras are not designed for those voltages. No manufacturer designs in a 10 to one safety factor.

Not a Number · 12-31-2014, 07:57 AM

Originally posted by wildlifephotog

The 285 is 350 volts and the 285HV is 12 volts.

It depends on the 285. It is only the very early manufactured units that have 350 volt trigger voltages. The Vivitar 285 that I bought new in 1982-83 measures out at 5.36 volts maximum with fully charged NiMH batteries.

wildlifephotog · 12-31-2014, 09:42 AM

I was going by what Vivitar themselves said, as was quoted on Photo trigger voltages.

"Alan Latafat Correa checked with Vivitar and they clarified:
The 285HV has a voltage of 12V. The 285 has a voltage of 350V."

01-25-2010, 01:37 PM	#18
ma318 Senior Member Join Date: Jul 2009 Location: BC, Canada Photos: Gallery Posts: 174	The reality is that without the maximum voltage stated in the manual anything, other than a Pentax flash, mounted on the hotshoe is "potentially" not safe. The radio triggers are definitely "safer" but without the the voltage stated in the manual, Pentax does not have to fix any damage unless you are using a Pentax flash. Last edited by ma318; 01-25-2010 at 03:45 PM.

12-31-2014, 09:42 AM	#30
wildlifephotog Inactive Account Join Date: Nov 2008 Location: USA Posts: 924	I was going by what Vivitar themselves said, as was quoted on Photo trigger voltages. "Alan Latafat Correa checked with Vivitar and they clarified: The 285HV has a voltage of 12V. The 285 has a voltage of 350V." Last edited by wildlifephotog; 12-31-2014 at 09:54 AM.

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01-24-2010, 12:01 PM	#16
ma318 Senior Member Join Date: Jul 2009 Location: BC, Canada Photos: Gallery Posts: 174	Originally posted by ryan s Reverse polarity = most flashes use the bottom, center pin as the +, and the little metal pieces inside the "shoe slot" are the ground. Some are the opposite and use the center pin as ground. And on this issue, I'll say...come on people. I know old flashes are cheap/free...either sell them and buy one of the boatloads of good flashes for under $100 (Nikon SB series...love my 24)...buy a Safe Sync...buy a hotshoe -> PC adapter...buy a wireless flash solution...something. Don't risk a mutli-hundred dollar camera with a free flash. The worst that could happen is you kiss your flash circuits goodbye, and we'll probably laugh and say "told you so." Wait...that's not very good I think your suggestion is appropriate for majority of the people out there. But for the sake of the new camera users who do not know any better and just happen to have one of those old flashes sitting around and for the sake of the real tinkerers who like to do weird and creative things with their old flashes, Pentax should publish the maximum trigger voltage and current and write a clear caution statement regarding older flash in the manual. This should actually help them sell more cameras to those tinkerers and prevent, to a certain degree, the uninformed newbies from blowing up their camera. Note: I think most hotshoe to PC adapter may not provide high voltage protection. If your camera has a build-in PC port, then the PC port is protected from "high" voltage. But this protection does not extend to its hotshoe. Last edited by ma318; 01-24-2010 at 08:50 PM.

01-25-2010, 01:13 PM	#17
ryan s Veteran Member Join Date: Jan 2008 Location: Madison, WI Photos: Gallery Posts: 2,383	Originally posted by ma318 I think your suggestion is appropriate for majority of the people out there. But for the sake of the new camera users who do not know any better and just happen to have one of those old flashes sitting around and for the sake of the real tinkerers who like to do weird and creative things with their old flashes, Pentax should publish the maximum trigger voltage and current and write a clear caution statement regarding older flash in the manual. This should actually help them sell more cameras to those tinkerers and prevent, to a certain degree, the uninformed newbies from blowing up their camera. Note: I think most hotshoe to PC adapter may not provide high voltage protection. If your camera has a build-in PC port, then the PC port is protected from "high" voltage. But this protection does not extend to its hotshoe. They should do that, although I bet they'll get people saying "the manual said xxx, and mine was xxx...but something's wrong" Then you get into variances of multimeters and all that. For example, my "average" meter that most folks have doesn't show an absolute 0 reading for impedance...more like 1.5 Ohms. I'd have to wonder how far it's off once the voltage starts going to 400+. I have no idea if the hotshoe -> PC provides a safe connection...it's been a while since I read about them, and I use wireless triggers anyway.

01-25-2010, 03:14 PM	#19
wildlifephotog Inactive Account Join Date: Nov 2008 Location: USA Posts: 924	Pentax is ISO 10330:2002 compliant. That sets a 25 volt standard on the flash voltage. If you think printing anything in the manual would help, I doubt it. You know how many times folks have to be told RTFM? Good tinkers would check out the info before doing anything possibly bad for the camera. Any Pentax flash will work. And all the new top 3rd party flashes will work if marked for Pentax. Other than that, you have to play on your own dime.

01-25-2010, 03:42 PM	#20
ma318 Senior Member Join Date: Jul 2009 Location: BC, Canada Photos: Gallery Posts: 174	Wildlifephotog, you sound like you know what you talking about. That's good enough for me. Thanks for the info.

01-25-2010, 04:22 PM	#21
justDIY Senior Member Join Date: Jan 2010 Location: Manistee, MI Posts: 295	The manual states to use a Pentax flash with my Pentax camera ... would that include the Pentax Takumar AF14 Flash, from twenty some odd years ago? I've got one coming in the mail, for basically the cost of shipping. I'll be testing it with a multimeter before mounting it up.

01-25-2010, 04:49 PM	#22
ma318 Senior Member Join Date: Jul 2009 Location: BC, Canada Photos: Gallery Posts: 174	I don't have such a flash so I don't know for sure. Maybe someone who has one will let you know. If you are following the instructions exactly in your manual then you should be in good shape. Since it is a used flash and you don't really know the condition it is in, you should always put a fresh set of new batteries in and check its trigger voltage to make sure it is safe. It is a very easy thing to do. That will give you the peace of mind. Last edited by ma318; 01-25-2010 at 05:01 PM.

01-25-2010, 08:24 PM	#23
ryan s Veteran Member Join Date: Jan 2008 Location: Madison, WI Photos: Gallery Posts: 2,383	Originally posted by justDIY The manual states to use a Pentax flash with my Pentax camera ... would that include the Pentax Takumar AF14 Flash, from twenty some odd years ago? I've got one coming in the mail, for basically the cost of shipping. I'll be testing it with a multimeter before mounting it up. I had an AF16 (pretty sure it was) and it tested low. Definitely check yours out before mounting since it's not listed here Photo Strobe Trigger Voltages

11-22-2013, 07:14 AM	#24
ChopperCharles Veteran Member Join Date: Jan 2010 Location: Durham, nc Photos: Albums Posts: 953	What is considered "high" voltage? I have a Vivitar Auto Thyristor 225 that I use on my Q, and it has a 35v trigger voltage. Charles.

11-22-2013, 09:11 AM	#25
GibbyTheMole Veteran Member Join Date: Nov 2009 Location: Iowa Photos: Albums Posts: 2,275	Originally posted by ChopperCharles What is considered "high" voltage? I have a Vivitar Auto Thyristor 225 that I use on my Q, and it has a 35v trigger voltage. Charles. That's too high from what I've read. 24 volts is considered the maximum "safe" voltage for any Pentax DSLR, and personally, I like to stick to 12 volts or less just to be on the safe side. I'm not sure if the Q is the same as their DSLRs, but I'd guess it probably is. I'd stop using that flash immediately, or buy a Wein Safe Sync if you really want to keep using it. I use Sunpak 422D flashes with my Pentax K-x bodies and the Q. It's a great and cheap flash unit with a trigger voltage of around 6 volts.

12-30-2014, 11:51 PM	#26
LXNights Senior Member Join Date: Feb 2011 Location: New England Photos: Gallery Posts: 150	I have a Vivitar 285 and Sunpak 622. DO you think those are safe to use with current Pentax cameras like the K-7, K-5, K-50, K-30, K-3, etc.?

12-31-2014, 03:54 AM	#27
MPrince Veteran Member Join Date: Sep 2006 Location: WV Posts: 1,495	Originally posted by LXNights I have a Vivitar 285 and Sunpak 622. DO you think those are safe to use with current Pentax cameras like the K-7, K-5, K-50, K-30, K-3, etc.? The only sure way to know is to check the trigger voltage. Buy or borrow a digital multimeter (you can buy one for under $10), then do a google search for how to check the trigger voltage. It's pretty easy, and will give you peace of mind.

12-31-2014, 04:37 AM	#28
wildlifephotog Inactive Account Join Date: Nov 2008 Location: USA Posts: 924	LXNights: The 622 is safe. The 285 is not. The 285 is 350 volts and the 285HV is 12 volts. The damage probably won't happen on the first use. It will likely happen from continued use and that is what destroys the electrical components. Using old high voltage flashes is false economy. They were built and used when actual metal contacts handled the voltage in the camera. The components used in modern electronic cameras are not designed for those voltages. No manufacturer designs in a 10 to one safety factor.

12-31-2014, 07:57 AM	#29
Not a Number Moderator Join Date: Mar 2012 Location: Venice, CA Posts: 10,526	Originally posted by wildlifephotog The 285 is 350 volts and the 285HV is 12 volts. It depends on the 285. It is only the very early manufactured units that have 350 volt trigger voltages. The Vivitar 285 that I bought new in 1982-83 measures out at 5.36 volts maximum with fully charged NiMH batteries.