Originally posted by bobbotron This v6 trigger is set to TX, linked via a 3.5mm cable.
As @BrianR has pointed out, you don't need that intermediate V6 in a TX role.
The LV5 sensor can trigger another receiver (and hence camera) or flash via radio.
The only snag you may potentially hit is an incompatibility between the LV5 and the RF60 firmware versions. Potentially, you might need to downgrade the RF60 firmware version to an earlier one, so that the RF60 can still talk the older flash protocol used by the LV5 sensor.
BTW, if you can place the LV5 sensor near the camera/flash, you could even fire the camera/flash directly without involving radio communication.
Originally posted by bobbotron Cactus flash, set to manual mode multi flash mode, attached to a V6 trigger in receiver mode (I've found this is a lot more reliable for whatever reason)
Again, the use of an additional V6 unit in a RX role is not necessary as your Cactus flash has a built-in radio receiver already. Currently you are using two superfluous units that only introduce lag.
If you have reliability issues with firing the flash directly from the LV5 sensor than try angling the flash body slightly differently (while compensating with the flash head). Alternatively, try using a different flash channel, making sure you go beyond five. The first five channels on the older flash protocol used on the LV5 all use the same frequency (to implement a poor man's approach to group broadcasting).
Originally posted by bobbotron So this all works, *except* the V6 trigger only seems to trigger the K3 about once every 4th shot.
I suspect this is due to the LV5 generating a trigger signal that is too short (unless the failed trigger events are due to the camera going into a sleep mode from which it has to sloooowly wake up before it can respond to a trigger event).
Are you running the LV5 sensor in "Multi" mode?
If so, switch it to "Single" mode and with a bit of luck the extra trigger signal padding that is then used will be sufficient to reliably fire your camera.
BTW, a long time ago I wrote a
review about the LV5 that you may find useful. I only tested the version without the useful "delay" and "freeze" controls, but it is unlikely that you'll need these features in your application (except perhaps the "freeze" control if you are suffering from too many subsequent trigger events).
Originally posted by photoptimist Wouldn't you trigger the K-3 first with some longish shutter time so the shutter is fully open when the strobes fire?
That is one approach and most recommended if the camera lag time is either
- too long to allow capturing an event, even when placing the "laser fence" such that it is broken long before the moving object (here the arrow) hits the scene of impact, or
- too variable. The camera, depending on what is currently processing internally, does not always have the exact same response time. Flashes are not only significantly faster to respond but also with much less variability.
@bobbotron If you want to keep firing the camera (instead of the flash) then I would recommend to connect a V6 in RX mode to the camera in order to trigger it, and use a V6 mode in TX mode (using a different channel) on top of your camera to trigger your flash. That way, you won't have to manually achieve synchronisation between camera and flash.
However, in your application it seems more promising to reduce the ambient light to a level that allows a longer exposure so that the flash will decide the exact point of exposure, not the camera.