Bronica etrsi flash voltage ?

Discussion in 'Medium Format' started by tom_choate, Dec 1, 2012.

  1. I have a etrsi and am wondering if I can use any of the many flashes available without harming the camera ?
    I have read so much of how some flashes can fry the circuits of cameras that I'm a little bit leery. I know that on Digital camras you must be very careful but I'm unsure when it comes to older cameras such as my Bronica. Specifically, I have a Vivtar 352 flash I'd like to use with my Bronica. I have this flash so thought why not use it ? I have used it with my Yashicamat's with no harmful effects. thanks in advance for any info.
     
  2. No problem. When these items were new people just connected them up and used them.
    Most of what you hear about sync. voltages and digital cameras is paranoia and mythology anyway.
     
  3. I'd be careful. The links here are worth a look:
    http://forums.steves-digicams.com/flash-external/129242-trigger-voltage-limits-modern-digital-cameras.html
    With the Bronica it's either a PC connection or SCA connection to a dedicated TTL flash.
     
  4. paul ron

    paul ron NYC

    The ETRS dosen't care about flash trigger voltage since the trigger is mechanical, not eletronic as in digital cameras today.
    Use any flash n don't worry about a thing.
    In fact plug your toaster in while you work n coffee maker too.
    HAve fun!
     
  5. paul ron

    paul ron NYC

  6. Most of what you hear about sync. voltages and digital cameras is paranoia and mythology anyway.​
    Early electronic flash used 415V dry cell batteries or AC adapter packs, applied up to 600V to the flash tube with the flash sync completing the circuit for the flash tube and applying the full voltage of the flash tube to the sync contacts as well as up to 10 amps of current.
    This makes for short life of flash sync contacts in leaf shutters designed for lower voltage flash sync and cooks thin printed circuit strips found in older SLR cameras and totally destroys digital circuitry.
    There are many studio flash still in use that apply higher than 6V to the flash sync and up to 2 amps sync current. Dedicated flash units usually apply 6V or less to the sync contacts with a few milliamperes of current but older models do not.
    High sync voltage problems are definitely not a myth or paranoia.
     
  7. "The ETRS dosen't care about flash trigger voltage since the trigger is mechanical, not eletronic as in digital cameras today."
    Also true of the SCA connection hooks up to the OTF TTL metering system in the ETRSi???
     
  8. Thanks for all the varied responses. I have learned quite a lot from them.
     
  9. paul ron

    paul ron NYC

    Charles Monday, Dec 01, 2012; 04:54 p.m.
    Most of what you hear about sync. voltages and digital cameras is paranoia and mythology anyway.​
    Early electronic flash used 415V dry cell batteries or AC adapter packs, applied up to 600V to the flash tube with the flash sync completing the circuit for the flash tube and applying the full voltage of the flash tube to the sync contacts as well as up to 10 amps of current.
    This makes for short life of flash sync contacts in leaf shutters designed for lower voltage flash sync and cooks thin printed circuit strips found in older SLR cameras and totally destroys digital circuitry.
    There are many studio flash still in use that apply higher than 6V to the flash sync and up to 2 amps sync current. Dedicated flash units usually apply 6V or less to the sync contacts with a few milliamperes of current but older models do not.
    High sync voltage problems are definitely not a myth or paranoia.

    I repair RB67s that have been in studios for years n years of pros n never seen this mythical wear of the contacts in leaf shutters you talk about.. NOT TRUE AT ALL!

    My RB has used my masher for over 40 years ajnd I also used a Balcar 6 head studio flash for almot 15 years... still no wear! Show me where you got that from? this is exactly how myths get started!
    Electronic cameras, digitals, are the ones that ARE sensative to being zapped by old flash units.. they are computers not cameras. That is not a myth!
    Hook up my Sunpac 611 potato masher n see what happens to your Cannon Digital junker.. ZAPPPP.... phit!
    Ah that first puff of smoke in the morning is so nice. . .
     
  10. I have run across 3 or 4 Kodak Supermatic, Wollensak Betax shutters that had the flash sync contact points heavily carboned and at least 1 that had the copper flash strip burned the length of the strip from high sync voltages and/or high current.
    Leaf shutters made from the 1960's to date most likely will not show this type of condition unless used with electronic flash units made in the 1940's to the 1950's.
    Graflex Strobe 250 and Strobe 500 step up a 415V battery to 600-800 volts to the flash tube. I can look it up on the schematic tomorrow if needed.
    Leaf shutters use contact points connected to the flash sync socket that move .010 to .020 inch to close the circuit to fire the flash. High voltage arcs across the sync contacts as they get close together creating a carbon build up that provides a high resistance to the sync circuit and effectively blocks the sync form occurring.
    If you have not seen carboned or burned sync contacts you have not worked on old enough equipment. I'll send you a picture of one next time I run across one. The most common problem I currently run across is oxidation of the contacts requiring polishing to get them to work.
    I would be hesitant to connect either my Nikon SB24 or Metz 45CT5 to a digital camera.
     
  11. paul ron

    paul ron NYC

    I've seen oxidised contacts, never burned because of high voltage.. and I have bene repairing admn restoring cameras back as far as the 60s... on much older including LF shutters
    So where do you get this fact from? I think you are confusing your opinions based on a few freak sutters you've come accross n haven't really seen enough to say this is true for ALL leaf shutters..
    it;'s just your generalization based on a few samples! NO NO NO.. it doesn't work like that.. how long have you been repairing cameras?
    Don't start rhumors n myths?
    If your camera has a printed circuit board.. it's an electronic junker not a camera!
    .
     
  12. Early electronic flash used 415V dry cell batteries or AC adapter packs, applied up to 600V to the flash tube with the flash sync completing the circuit for the flash tube and applying the full voltage of the flash tube to the sync contacts as well as up to 10 amps of current.​

    This doesn't happen.

    To fire a Xenon flash tube, a small capacitor (about 10nF) is charged from the main high voltage source via a high value resistor (about 470K to 1M). The small charge in this capacitor is discharged through the shutter contacts into a small trigger transformer. This creates a short high voltage pulse which ionises the xenon gas in the tube making it conductive. As the two main terminals of the tube are connected directly to the high voltage capacitor, the tube conducts until all of the charge in the capacitor has been discharged and then the gas returns to a non-ionised and non conductive state allowing the capacitor to charge up again. In newer flashes a pair of thyristors shut off the current when enough light has been output. This also de-ionises the gas making the tube non conductive and leaves some charge in the capacitor leading to faster re-charge times.
    The current through the flash tube does not go through the sync. contacts. If it did, most shutters would be single use items!
    Electronic cameras, digitals, are the ones that ARE sensative to being zapped by old flash units.. they are computers not cameras. That is not a myth!​
    I partially disagree with this too. Most electronic cameras will use an opto-triac or thyristor to fire the flash. The most common types are rated at 400 volts. I couldn't actually find one rated as low as 250 volts although that's what most DSLR manufaturers recommend. Quite a large margin for error.
    I took apart my cheap wireless flash trigger to see what was in it and it was a 400v rated opto SCR. I haven't taken an electronic camera apart to see what they use but I would be very surprised if it wasn't something similar. If I was designing a camera, this is what I would use. Only an idiot of a camera designer would produce a design which would be destroyed by flashes which are currently in existence when the inclusion of a $0.02 component would prevent it.

    The usual myth is that a flash is o.k. on a sync. socket but not on a hot shoe. In reality the two will either be connected in parallel or have similar circuits. I think the main worry is in sliding a charged flash onto the hot shoe and having the centre pin momentarily touch one of the other pins and causing damage.
     
  13. paul ron

    paul ron NYC

    AS a preventative measure there are "safe flash shoes" soild state triggers, opto isolators in the HV circuit separate from introducing any voltage to the electronics perhaps more to prevent static build up from zapping the computer portion of the cameras today.... this is the sensative part of digitals.
    In old mechanical cameras; they aren't effected at all.. plug your coffee maker in, rum your circular saw of em.....
    You can do a google search for DIY safe triggers that are easy projects using very few components.
    .
     
  14. For many, cheap radio triggers solve these worries--real or imaginary--and add a huge helping of flexibility/creativity in Strobist style lighting set-ups. Jeez, when OK quality trigger sets are 25-30 bucks, why worry or take chances with frying any camera?
     
  15. paul ron

    paul ron NYC

    Yes a very practical solution.. I am looking buying a set of radio triggers but have no idea what to get yet.. Chrtistmass shoping righ now.. B&H here I come!
     
  16. Paul, get some cheap i-Shoot triggers off the internet. I've been using some as pictured below for 2 years or more and they've never let me down. They'll fire anything using the fairly comprehensive kit of adapters provided in with the price.
    Joe likes this. ;/
    00b5RW-506709784.jpg
     
  17. Graflex Strobe 500, Singer Graflex Division 1971 schematic attached. Socket P-2 is the trigger socket. Definitely applies 450VDC to the contacts.
    Strobe 500 is a 200WS handle type strobe.
    Contact me if you need the complete service manual.
    00b5VZ-506745584.jpg
     
  18. paul ron

    paul ron NYC

    Exacly what I need Joe. Can I fire 2 flash units with that system? Can I buy another remote for it?
    Thanks. Christmass lsit is being made.. Dear Santa.. ask Joe waht I need so you cna ge the make n model numer please? If you get this for me, Santa, I'll let you see my pictures next year?
    thanks... BTW any schematics for a Sunpac 611?
     

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