Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
05-16-2012, 01:13 PM   #1
Site Supporter




Join Date: May 2012
Location: Colorado
Posts: 107
K-r internal flash trigger voltage limit

I just ordered a an old Vivitar Thyristor 3500 flash unit to help me with macro photography. It has just come to my attention that some old flash units can damage modern SLRs...

I have seen the trigger voltage on the vivitar reported to be anywhere between 7-9 volts. What is the official limit for the my k-r? Has anyone ever actually damaged the flash trigger and it it an expensive fix?

05-16-2012, 03:33 PM   #2
Site Supporter
jatrax's Avatar

Join Date: May 2010
Location: Oregon
Photos: Gallery | Albums
Posts: 10,770
Here is a link to some reported voltages.

I have seen posts that say 24 volts is OK for Pentax but I tend to be conservative and go with 12 volts. Some flashes go well over 100 volts and those are the ones you need to stay clear of. The Vivitar 3500 is listed at 6v and also at 9.1 so some variability in individual flashes or testing method.

Yes, over voltage can damage the camera. No idea what the cost to repair would be but not cheap.

Do a search for "how to test flash voltage" and you will find ways to test your flash.
05-16-2012, 04:55 PM   #3
Veteran Member




Join Date: Nov 2009
Location: Iowa
Photos: Albums
Posts: 2,269
If the flash has a trigger voltage of under 12v, you should be ok. Otherwise, I wouldn't chance it.
05-17-2012, 05:45 AM   #4
Veteran Member
sterretje's Avatar

Join Date: Dec 2008
Location: Roodepoort, South Africa
Photos: Gallery | Albums
Posts: 3,534
If it's too high, you can add a Wein safesync (google it) or similar. I seem to recall that the Cactus triggers also have a protection circuit.

PS There is a user (I always forget the name) here who has used a 100V-or-so flash on a Pentax dSLR camera (not K-x).

05-17-2012, 08:42 AM   #5
Veteran Member
Anvh's Avatar

Join Date: Sep 2011
Posts: 4,616
Pentax have said they are conform to the standard and the standard uses 24 volt.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
camera, flash, k-r, kr, limit, pentax k-r, trigger, vivitar, voltage
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Is the flash trigger voltage the same in the PC sync cord? ismaelg Flashes, Lighting, and Studio 13 02-23-2012 09:31 AM
High voltage flash + optical trigger kp0c Flashes, Lighting, and Studio 5 02-16-2012 12:31 PM
Trigger voltage? - Lester A Dine Clinical Box Power Supply Model II (ring flash) Nick Siebers Flashes, Lighting, and Studio 5 02-10-2011 11:50 PM
Flash trigger voltage and how it relates to radio triggers joshnl Flashes, Lighting, and Studio 7 07-28-2010 04:01 PM
External Flash Trigger voltage for the ... roscot Pentax DSLR Discussion 3 07-27-2007 12:06 PM



All times are GMT -7. The time now is 12:10 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top