At a recent event I tried to use an on-camera speedlight (SB-800) as a master and a off-camera speedlight (again SB-800) in a CLS setup where I would hopefully use the off-camera flash as a silhouette light.
(CLS = Nikon Creative Lighting System – where you can remotely fire flash using TTL – either with the on-bard flash (on some cameras) or another speedlight set to master. As well as using TTL you can also add compensation values to each group of remotes from the master.)
Although I’d tested them before getting into position (so channels and groups were fine) – the remote flash just didn’t fire. It was relatively in line of sight so that shouldn’t have been the issue, however with the speedlight facing forward the detector would be at the side of the speedlight and it was behind a shoot-through umbrella. I now think that possibly the combination of these meant that the signal from the master speedlight wasn’t getting through to the remote. It was also in a party environment so there were other lights which may have caused issues.
Turning the shoot-through umbrella to a bounce one may have worked (it’s a convertible umbrella), but there wouldn’t have been time for that.
Taking the umbrella off may have also helped, I should have tried this but alas didn’t.
In the past I’ve used a remote flash like this but using a radio trigger rather than Nikon CLS system.
I didn’t go for this setup on this occasion as I needed a on-camera speedlight as it was too dark without it.
So alas I made do without the remote speedlight.
After the event I investigated the option of using an on-camera speedlight but also a radio-triggered remote and my results are below.
Only one Hotshoe
The initial issue is that cameras only have one hotshoe. The on-camera Speedlight obviously needs to go in this. However most radio-triggers are also designed to go in this. They both can’t.
Thankfully there are a set of other connectors available.
PC socket: The PC socket is the standard/traditional method of firing flash via a cable.
My D800 has one:
And so does my SB-800’s:
Usually you’d use the PC sync on the speedlight to fire the speedlight itself i.e. incoming signal. However it appears that this socket is by-directional.
Sync Connector: It transpires that in addition to having the Skyport trigger via the hot-shoe there is also an additional SYNC connector:
The Sync connector on the Speedlight is smaller than the usual jack – it’s a 2.5mm jack socket rather than 3.5.
So the cable needs to be a 2.5mm jack to PC sync connector.
Thankfully one of these is supplied with skyport transmitters. I hadn’t taken it out of the wrapper let alone out of the box so I wasn’t really aware of it until investigating this issue.
Connection + Test
I wasn’t sure if it would work correctly and wasn’t sure which PC sync to use – the camera or the speedlight. My thoughts were that if the on-camera speedlight was in TTL that there may be a flash sync speed issue, particularly with the TTL pre-flashes. So I tried both.
Standard settings – both worked.
Pushing shutter speed up to 1/250th – both worked!
(My skyport are the “SPEED” variety so are faster than the older non-speed variety)
To reiterate, the setup is:
Remote Speedlight: Set to manual power, skyport receiver plugged in to the PC sync port.
On-camera Speedlight: Set to TTL, mounted on camera hotshoe.
Skyport Trigger: Connected by above cable, to PC sync port of either camera or on-camera speedlight.
So in future I may try this in such scenarios. It’s handy to know that it’s possible to mix TTL/CLS and manual radio triggering.
Worth noting of course – since operated by a standard “GO” signal radio trigger- you can’t control the power from the camera. Pocket wizard have made TTL capable radio triggers (FlexTT5/MiniTT1 for firing and AC3 controller for varying power) but they’re considerably more expensive that simpler radio triggers that just send a “go” command.
Found an additional issue worth noting:
Not wanting the skyport trigger dangling by a cable which can come out I considered mounting the trigger to the speedlight via something like velcro or elastic. In testing this I found that if you place the trigger flat against the speedlight – trigger: the flat side with buttons, speedlight: on top of the flash head – that the signal would not get to the receiver. I imagine this is due to interference from the pulse of the speedlight firing. Instead I think I’ll attach the trigger to the side of the speedlight with elastic.