A later communication from Paul C. Buff
------------------------------------------
Hey Chuck,
What is this "film" you speak of? And isn't that the camera Mathew Brady
used?
All kidding aside, the close time is about 50 micro seconds. I do not
know if that is enough for the bulbs. I have an old bridge camera that
cannot be triggered by them due to the shutter lag. I understand the
timing theory (Pocket Wizard call that HyperSyncing, as though it is
new), but I cannot speak of any practical experience with that set up.
I hope this helps, and if there is anything else we can do to assist,
please let us know!
Thanks
David
Paul C. Buff, Inc.
1-800-443-5542
------------------------------------------
Chuck Norcutt
On 4/26/2011 10:11 PM, Tim Hughes wrote:
> Hi Mike, I have not followed this thread, so am guessing a bit here
> . The cybersync units are rated to trigger up to 300V , so almost
> definitely use an SCR switch. The scr drops about 1.2V when
> triggered, so severly limits the voltage from a 3V battery when
> triggering a flash bulb. . The Cybersync units are rated to trigger
> either positive or negative polarity. This likely requires an
> additional diode which drops another 0.7V or 1.9V total. So not
> surprising they cannot fire a 3V powered flash device.
>
> At 3V the flash bulb likely takes a lot longer to fire. This is
> because the current must heat up the magnesium wire to ignition
> point. The heat is supplied at a rate proportional to Volts
> squared. So all else being equal the difference in heating rate
> (delay) between 22V and 3V is ~40+ times! In reality the current
> available is limited by both the voltage and the internal resistance
> of the battery/capacitor combination. That is why a capacitor in
> good working order is important in the flash unit. An old dried out
> capacitor cannot provide high current. If you send me a picture of
> the old capacitor with measured dimensions, I may be able to help
> you find a replacement. There are some very small rechargeable Li
> batteries that are now capable of high current, which might work
> well here, even without a capacitor as they can deliver more than
> 1A. Contact me off list for more info.
>
> It depends on how they drive the SCR, but in general once triggered
> the scr continues conducting until the current drops off to a small
> value. So it is fairly likely their is no trigger duration
> limitation here.
>
> In OM2N's there is a series diode (1N4004) to isolate the pc
> connector from the hot shoe. This drops 0.7V if using the pc sync
> connector. The OM2s uses an scr, so drops even more.
>
> Tim Hughes
>
> --- On Tue, 4/26/11, usher99@xxxxxxx<usher99@xxxxxxx> wrote:
>
>
> From: usher99@xxxxxxx<usher99@xxxxxxx> Subject: [OM] Can Cybersync
> battery receivers/transmitters trigger a large flash bulb? To:
> olympus@xxxxxxxxxxxxxxxxx Cc: timhughes@xxxxxxxx Date: Tuesday,
> April 26, 2011, 5:01 PM
>
>
> Hi Chuck,
>
> Thanks for asking about the Cybersyncs. Yep, still plenty of
> flashbulbs of various flavors yet to go. I found the "mother load"
> at my mother's of course. Most numerous are the GE 6B's. I would be
> happy to sacrifice one in the name of science.
>
> I did like your analogy of lighting a candle in triggering the FB.
>> From my digging around about this, the older cheapo FB brackets
>> just
> used 3V or so to start the burn--less reliable and I suspect
> requires a more prolonged current to ignite. Now I sprung a bit more
> dosh for a replacement 22.5 V battery in lieu of the two D cell
> solution and it has a cap at the end battery module for the FB
> bracket. I searched around for new caps, but I couldn't find any,
> though I am no expert at finding oddball caps.
>
> I tried a few bulbs to see if it fired reliably with the PC socket
> before (on the 2N but not the OM2 I was using) and it seemed fine
> even with another auxiliary FB hooked up in a floor lamp. I wouldn't
> think a very long pulse with the cap in the circuit would be
> necessary--perhaps it is leaky. I kinda -sorta remember though that
> the cheapo yabe radiotriggers would not even fire some electronic
> flashes, but perhaps I am misremembering an old post. I must say I
> was very surprised and disappointed the FB didn't fire with the
> radiotrigger in the hotshoe. Perhaps I should have tested the cap
> specifically and not just assessing if the FB would fire.
>
> I bet Tim would have a handle on this. I'll cc him this directly.
> Haven't heard form him for awhile. Hope all is well.
>
> I too am enamored of the FP option and had visions of macro fill
> flash at any speed using various size FP FB's radio triggered with
> various diffusers. A more flexible and more powerful F280, No? So
> far mostly a thought experiment . I am still curious if TTL auto
> mode will meter the FB's properly in FP mode. Now Xsync will still
> work with the FP FB's , but one must drag the shutter quite a bit
> for it to work well --not as elegant.
>
> Still in the Dark, Mike
>
>
>
>
> I sent the following reply to Paul Buff, Inc. after receiving a "we
> don't know about FP timing" reply from their tech support. Got any
> bulbs left, Mike? Maybe I can loan you my CyberSyncs sometime after
> I get home Wednesday night. I'm interested to know the outcome.
>
> Chuck Norcutt
>
>
>> -------Original Message------- From: chucknorcutt [at]
>> chucknorcutt.com To: Info at Paulcbuff.com<info [at] paulcbuff.com>
>> Subject: RE: Can Cybersync battery receivers/transmitters trigger
>> a
> large
>> flash bulb? Sent: Apr 26 '11 11:24
>>
>> Thanks for the reply, David.ÂÂMy guess is that you're much younger
> than my
>> 67 years since you appear to have little knowledge of FP (focal
> plane) flash
>> bulbs.ÂÂThe camera I mentioned (an Olympus OM-2) is a mid-70s film
> SLR and
>> the last of the OM line of cameras to support FP synchronization
> (focal plane
>> flash bulbs) as well as X sync for electronic flash.ÂÂSelection of
> the sync
>> speed is via a two position switch near the lens mount.
>>
>> You are correct about the timing for FP bulbs.ÂÂUnlike electronic
> flash
>> (which can only be fired at shutter speeds slow enough that both
> curtains of
>> a focal plane shutter are fully open), FP bulbs are
> specificallyÂÂdesigned
>> for use with focal plane shutters and can be used at any shutter
> speed.ÂÂThey
>> have a very long burn time which, to assure compete coverage of
>> the
> image
>> plane, must be at least as long as the X-sync time for the camera.
> For the
>> OM-2 that's at least 1/60 second and I suspect large FP bulbs may
> have burn
>> times of 1/30 second or longer for the even larger and
> slower-shuttered
>> medium format SLRs of the day. In addition to the long burn time
> there is
>> also an extended ignition time.ÂÂThat simply means that it takes
>> the
> bulb
>> some appreciable time to start burning at a constant rate which is
> necessary
>> for even illumination as the slit formed by the focal plane
>> shutter
> traverses
>> the image plane. So, you are also correct thatÂÂthe timing for FP
> sync trig gers the bulb well before the shutter starts to open.ÂÂI
> appreciate the information on the 1/4000th latency of the
> CyberSync.ÂÂI don't have precise knowledge of how that will affect
> an FP bulb but suspect that something that fast is in the range of
> random noise for something with the long ramp up time of an FP bulb.
>>
>> What I had hoped you might be able to supply me with was the
>> amount
> of time
>> that the CyberSync trigger signal is actually being transmitted.
>> Our
> concern
>> is that it might not be long enough to assure reliable
> ignition.ÂÂIt's sort
>> of like trying to light a candle with a match.ÂÂIf you place the
>> lit
> match in
>> contact with the candle wick for 1/10 second you're not likely to
> light the
>> candle. Any signal duration timing info you have will be
>> appreciated.
>>
>> It's possible I may simply lend my CyberSyncs (by mail) to the
> friend with
>> the FP bulbs.ÂÂIf I do I'll advise you of the outcome of the
> experiment.
>>
>> Chuck Norcutt
>>
>>
>>> ÂÂ-------Original Message------- ÂÂFrom: Info at
>>> Paulcbuff.com<info [at] paulcbuff.com> ÂÂTo: chucknorcutt [at]
>>> chucknorcutt.com ÂÂSubject: RE: Can Cybersync battery
>>> receivers/transmitters trigger
> a large
>> flash bulb?
>>> ÂÂSent: Apr 26 '11 10:24 ÂÂ ÂÂHey Chuck, ÂÂThanks for contacting
>>> us! Unfortunately, this has not been tested
> by us,
>> and
>>> ÂÂI am not familiar enough with those type bulbs to make an
> educated guess.
>> I
>>> ÂÂwould think if they can be triggered by jumping a sync cord,
>>> they
> can
>> likely
>>> ÂÂbe triggered by a CSRB with the correct wiring. However, some
> additional
>>> ÂÂthoughts on this: Are you using this with a typical DSLR, or
>>> do
> you have a
>>> ÂÂcamera designed to use these, and you just are looking for a
> wireless
>>> ÂÂsolution? My research has lead to my understanding that these
> need a sync
>>> ÂÂconnection that will trigger in advance of the shutter
>>> opening. A
> standard
>>> ÂÂsync connection will not do that, and cause the lights to
>>> trigger
> too
>> late.
>>> ÂÂAdditionally, regardless of the camera, the all radio remotes
> introduce
>> some
>>> ÂÂlatency. In the case of Cyber Sync, it is about 1/4000, which
>>> may
> or may
>> not
>>> ÂÂskew the timing of the trigger. ÂÂ ÂÂI hope this helps, and if
>>> there is anything else we can do to
> assist,
>> please
>>> ÂÂlet us know! ÂÂ ÂÂThanks again, ÂÂDavid ÂÂPaul C. Buff, Inc.
>>> ÂÂ1-800-443-5542 ÂÂ ÂÂ-----Original Message----- ÂÂFrom:
>>> chucknorcutt [at] chucknorcutt.com [mailto:chucknorcutt
> [at]
>> chucknorcutt.com]
>>> ÂÂSent: Saturday, April 23, 2011 9:25 AM ÂÂTo: tech [at]
>>> paulcbuff.com ÂÂSubject: Can Cybersync battery
>>> receivers/transmitters trigger a
> large
>> flash
>>> ÂÂbulb? ÂÂ ÂÂA friend has acquired a large flash gun and a
>>> supply of FP
> bulbs.ÂÂ
>> Assuming
>>> ÂÂthat a Cybersync transmitter is attached to a camera with FP
>>> sync
> (an
>>> ÂÂOlympus Om-2) will the receiver trigger the bulb? Another
>>> friend
> has
>>> ÂÂspeculated that radio triggers designed for electronic flash
>>> may
> not have
>>> ÂÂsufficient duration to trigger the bulb.ÂÂAdvice? ÂÂ ÂÂChuck
>>> Norcutt ÂÂEndwell, NY ÂÂ ÂÂ
>>
>
>
>
>
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