Oldskool Flashguns in parallel?

I have been using an old Sunpak455 auto candlestick flashgun with my Sony A200 by using one of those SYK-5 optical red-eye delay slaves quite sucessfully. I have just found another Hanimex TZ-2 auto flashgun in the loft which also still works OK.

My question is, can I run these simultaneously from the same slave (the Hanimex on the slave hotshoe, and the Sunpak via the PC sync plug on the slave side) or will the likely difference in open circuit voltage screw one/both up?

I probably knew the answer to this 20 years ago but now I can't remember.

Cheers, Ady
--
Out on Blue Six.
It's Chips and Jackets, Peas and Trousers.

It was quite common to do this, either using a double adapter or a Y junction cable. I believe the only problem you can have is that the synch cords are of opposite polarity and thus one flash triggers the other no actual harm done. I hardly ever used my adapter but it gave no trouble and I'm sure there was nothing inside. I have also used two flashes on the one radio receiver, which happened to have a shoe with a pc terminal on the side.

I tried this yesterday as my SB800 has a dual sync port (I replaced the silly 3 pin connector with a 3.5mm mono jack in parallel to the sync socket) and I wanted to fire 4 lights with 3 radio triggers. Using a radio trigger I can fire the SB800 and an SB600 but I cannot fire the SB800 with a vivitar 283. I guess there are differences in their sync circuitary so the answer is it may work, but some flashes might not be compatible with others.
----
http://www.dazedproductions.co.uk

Thanks, that sounds hopeful, looks like it's experiment time tonight!

Ady

--
Out on Blue Six.
It's Chips and Jackets, Peas and Trousers.

Well, That was singularly unsuccessful.

For some reason the SYK-5 won't fire the flash. The flash works OK on its own (when I push the test button in or short the hotshoe contacts), it fires whilst I attach it to the SYK-5, but when it's fully attached, the test button doesn't work any more, and the primary flash doesn't trigger it.

If I connect the Sunpak to the PC socket, this fires no problem.

Mystery. Looks like geko77 may have been right, I'll have to give the Hanimex up as a bad job if it doesn't work with optical slaves :-(
--
Out on Blue Six.
It's Chips and Jackets, Peas and Trousers.

an ordinary cheap optical save should fire it

itsDing said:

an ordinary cheap optical save should fire it
--

Click to expand...

Ah yes, but the reason I have to have the red-eye slave is because I have a Sony A200 where you can't turn off the focus pre-flash. I could try slaving the second slave off the first slave flash, but that's getting a bit out of hand LOL
--
Out on Blue Six.
It's Chips and Jackets, Peas and Trousers.

itsDing said:

an ordinary cheap optical save should fire it

Click to expand...

More like quite the opposite.

The cheapo dumb slaves are passive devices. Just a light dependant resistor, or something like it. As a consequence they are neither fully open circuit or fullu closed. You can be caught out by a flash with a low trigger voltage and when the slave is activated there isn't enough threshold voltage drop to trigger the flash.

It took me thirty years to find out that my flash had 5v at the trigger. It's failure to work with a dumb slave was the message. Incidentally it is a Hanimex two tube potato masher, but the problem could happen with any low voltage flash. I guess you need to be a bit unlucky with the slave too.

An intelligent slave is active and there is an opportunity to use a switching circuit, thereby solving the problem.

--

Well cheapo slaves fire my sunpaks, they ignore the preflash. Not with my Vivitars tho. However someone sent me a pic of a cheapo slave put into a 35mm film canister with a hole cut into it, the idea is that it only sees and fires with the stronger flash not the preflash, l will try it with my Vivitars.

itsDing said:

--
Well cheapo slaves fire my sunpaks, they ignore the preflash. Not
with my Vivitars tho.

Click to expand...

I guess that could only be down to problems of threshold voltage and is a matter of luck, good or bad, and the environment. In which case you could hardly rely on it.

What you say does reinforce the notion of some threshold problems. My camera will send a single flash with ten levels of output. I could never get the 5v Hanimex to fire but the 28v Metz will fire under all settings.

itsDing said:

However someone sent me a pic of a cheapo slave
put into a 35mm film canister with a hole cut into it, the idea is
that it only sees and fires with the stronger flash not the preflash,
l will try it with my Vivitars.

Click to expand...

Same thing. Even if these things work consistently, which is hardly likely, the situations in which you can sensibly use them are extremely limited. You will need full control over the camera, in which case you can be pretty sure you can suppress the pre-flash anyway, and therefore don't need to fritz around with all this junk, or the slave flashes are wound down so far to be just minor fill. I understand your Vivitar has a lot of manual control. If any of this works, you are going to need it.

An intelligent slave is about the most useless piece of gear you can have in your bag. The only use mine gets is as a dumb slave where it will fire the Hanimex with complete reliability.

I've just measured the voltages across the flashes, Sunpak 6.6v, Hanimex 230v !! So that may be the problem, the hanimex obviously needs a thyristor to trigger it which my little slave may not have.

I've been reading another thread where the guy built his own 'muti pre-flash' optical slaves with alternate transistor/thyristor triggers so I may build a couple of those.
--
Out on Blue Six.
It's Chips and Jackets, Peas and Trousers.

exclamation marks.

Adrian Layden said:

I've just measured the voltages across the flashes, Sunpak 6.6v,
Hanimex 230v !! So that may be the problem, the hanimex obviously
needs a thyristor to trigger it which my little slave may not have.

Click to expand...

The Hanimex is pretty typical of the older high trigger voltage flashguns, and studio flash, and any slave should be capable of firing it. It certainly does not need a thyristor to trigger it. It's the low voltage guns where the problem might lie, and I don't think it is that common there at that end either. It may be possible that the great disparity in trigger voltage between the flashes can give rise to a problem when firing both simultaneously. I don't see how but I guess all you need to do is test the flashes in the SYK-5 individually. I don't know how the SYK-5 works, anything on Google is just badly translated gobbledygook. The word "theory" turns up rather too often and I suspect that it does not actually count the flashes and fires on the last one, clearly the sensible way to do this job if you have to, so guess this is a device to be avoided in practice..

You might find this link useful, though it is more pertinent to the dangers of using high voltage flash on some digital cameras.

http://www.botzilla.com/photo/strobeVolts.html

Adrian Layden said:

I've been reading another thread where the guy built his own 'muti
pre-flash' optical slaves with alternate transistor/thyristor
triggers so I may build a couple of those.

Click to expand...

The SF-4 intelligent slave turns up on eBay from time to time. It works perfectly, handles high and low trigger voltages simultaneously, and costs about $25. The only reason why you would want to build one yourself is for the intellectual exercise.

But above all, you really need to consider if you really need to do all this. It is far from a good idea and you will be better off getting a camera more appropriate for flash photography.

(digressing)

You probably aren't so lucky that your camera has a hotshoe but, if it does, it might fire a single shot with the internal flash turned off. In that event, a cheapo radio link with an extra receiver may solve your problem. Just a thought.....