Anyone ever use one of these?

They could come in very handy for studio work as I could mount both my Godox controller and wireless remote shutter on the D850. My only concern is whether having two units on the same hot shoe contact might do something weird to the voltage and possibly damage the camera.

 

Any thoughts?

 

Dual Hot Shoe Flash Speedlite Light Bracket Splitter for Camera Canon/Nikon DSLR | eBay

Not exactly those. I did use PC cords to wire multiple flashes at once to hotshoe or PC plug in the past.

Voltage adding up is technically unlikely. With a lot of respect towards all even just potentially involved parties: Buying a digital Multi- or Voltmeter for about 10€/$ can improve your sleep quality drastically.

It is beyond my limited comprehension why the multi shoe device should wire both mounted units any other way than parallel, which should mean same voltage but twice the current on your sync contact.

Does the wireless remote use the flash shoe contacts, or only for support? The D850 has a 10-pin connector and USB 3 port for camera control, but the Godox needs the flash shoe for TTL. There is also a PC port, for triggering a non-TTL flash. If the rig is on a tripod, you could let the remote receiver dangle, or tape it to the camera somewhere.

For remote triggering, I've started to use my smartphone, bonus being that I can check the framing. I think you can do the same with the Nikon (in live view) and Snapbridge?

 

I'm using it mainly for self portraits: camera on a tripod, Godox controller and a couple of wireless strobes. Now if only I could adjust the flash power from the phone...

 

Still, it's handy for practicing lighting without an assistant.

The device shown comes in Canon and Nikon models, with the contacts arranged differently.

 

It should be not so hard to wire up the flash trigger contacts isolated, such that the voltage

didn't matter. But I suspect not for the price indicated.

 

Two of the same model, with the same voltage, might work fine together as far

as flash. The other contacts could get very confused, unless even fancier (more expensive)

logic was used.

No wireless shutter-remote works through the hotshoe; the hotshoe is just a mounting point, and a supplementary cable is needed to actually fire the camera. So a shutter trigger shouldn't care a fig about the hotshoe connections, nor apply any voltage thereto. You could even tape over the hotshoe contacts and it would still work as a remote shutter release.

 

However, if this device is to be used with multiple flash units, then caution is needed. It almost certainly won't work correctly with two speedlights/lites in i-TTL/e-TTL mode, since they'd need different camera 'handshakes' to work independently and correctly. This obviously can't happen if the control pins are paralleled in common.

 

Don't expect to be able to use, say, one direct flash for fill and another as bounce on that bracket in TTL mode and get anything like a balanced exposure! The duplicated flash dedication pins are completely bogus, and can't possibly work independently.

 

Trigger voltage shouldn't be an issue with any flash made in the last decade or so, but I certainly wouldn't risk mixing an old last-century device with anything more recent. Probably not good for the camera, nor for the flash with the lower trigger voltage.

(snip about wireless remote)

 

However, if this device is to be used with multiple flash units, then caution is needed. It almost certainly won't work correctly with two speedlights/lites in i-TTL/e-TTL mode, since they'd need different camera 'handshakes' to work independently and correctly. This obviously can't happen if the control pins are paralleled in common.

 

Don't expect to be able to use, say, one direct flash for fill and another as bounce on that bracket in TTL mode and get anything like a balanced exposure! The duplicated flash dedication pins are completely bogus, and can't possibly work independently.

 

Trigger voltage shouldn't be an issue with any flash made in the last decade or so, but I certainly wouldn't risk mixing an old last-century device with anything more recent. Probably not good for the camera, nor for the flash with the lower trigger voltage.

 

I suppose there is a tiny chance that two of the exact same model could work together, but any combination

of different models sounds like a bad idea. I don't know at all what the signals look like on the non-trigger pins.

 

Even a low trigger voltage flash might be surprised by a slightly higher voltage on its trigger pin.

 

The obvious way to design dual triggers is with opto-isolators, though that would need a power source

inside the device. I doubt that could be done for the price indicated.

 

Dual anything more than just trigger would require complicated circuitry, likely with

a microprocessor. And, as you note, some way to indicate that the lighting

effects might be different.

 

Duplicating the other pins does allow for one with trigger only along with another one

using all the pins, in either position. I believe either with or without opto-isolators.

Actually, if the polarity is standardized, just two diodes would be enough to keep

voltage out of the wrong one. I suppose that is possible for that price.

The trigger polarity on flashguns has been standardised as negative-earth for years, although some cheap and nasty flashguns made before ~ 1990 may have flouted that convention. As did some Courtenay studio strobes, who I believe are now long out of business.

 

Diodes would certainly work to isolate trigger voltages, but some modern flashes have an exceedingly low voltage on their trigger pin. I'm wondering whether the diode voltage-drop might prevent reliable triggering?

 

In any event, that dual hotshoe bar isn't a device I'd personally trust to fire two speedlights, even without TTL control. If I needed such a device, I'd use a bracket with two cold-shoes and fire the flashes using radio triggers. Or fit a single cold-shoe bracket and fire the flash fitted to it optically slaved to a camera-mounted flash.

Edited December 21, 2019 by rodeo_joe|1

(snip)

Diodes would certainly work to isolate trigger voltages, but some modern flashes have an exceedingly low voltage on their trigger pin. I'm wondering whether the diode voltage-drop might prevent reliable triggering?

 

(snip)

 

With Schottky barrier diodes, the drop is down to about 0.4V.

 

It is possible that even with that it is too low.

 

But those with voltage that low might not like even the 6V that Canon claims.