Compatibility with Pentax K3ii

Hi there, i own a Pentax k3II camera and two studio flashes made by interfit (model stellar 600w) -see attached photo-. The Pentax camera hasn't got a built in flash on it. Some friends recommend me the Cactus V5 transceivers. What do you recommend in order to control the studio flashes from my camera wirelessly?

Best regards 


  • You could use V5 triggers for triggering your strobes.

    You'd use one V5 on camera and at least one more V5 connected to a strobe with a small 3.5mm -> 6.5mm cable. The V5 include such a cable / adapter.

    Whether you need another V5 unit depends on whether your strobes support optical triggering, in which case the second strobe could be triggered by the first optically.

    If they do not support optical triggering then you have to add a third V5 unit and connect it with another cable to the second strobe.

    Note that the V5 don't support groups, but by setting one receiver to channel 2 and the second receiver to channel 3, you could use the channel selector on the transmitter to fire only one of the strobes (using channel 2 or 3), or both (using channel 1, which is a "multi-cast" channel).

    If you are going to include more light sources in the future, have a think about getting Cactus V6 instead. They do everything the V5s do (but you'd have to get the cable separately) but support much more flexible grouping (i.e., individual or combined use of multiple light sources). The V6 also support remote power control with many speedlights, but do not with strobes like yours.
  • Thanks for the reply! Can you please advise me where can i buy the V6 system?. I live in Greece.
  • Hello Nick,

    We do not have a Greece dealer at the moment so you may purchase directly from our official store as we ship internationally 3 times a week:

    FYI the cloest dealer would be the one in Sofia, Bulgaria.

    Thank you!
    Antonio Lao
    Brand Manager

    To help us better help you, always state the exact firmware version installed on your Cactus device(s), such as: "1.1.013", "FUJ.1.002", "v.103".

    For the time being, Cactus V6 (MK1) running on firmware version 2.1.001 can be triggered by a V6 II (MK2) running on Multi-brand HSS firmware (e.g. 1.1.013) and not by X-TTL firmware versions: PEN.A.001 and OLY.A.001.  No schedule has been released yet. 

    Cactus RF60X / RF60 Firmware versions A01 and A02 currently ONLY works with PEN.A.001 and OLY.A.001.  Other "A" version of X-TTL firmware will be released soon. For both Multi-brand HSS and X-TTL firmware versions (FUJ, SIG, SON), install firmware version 103 / 205 on your RF60X / RF60.

    Cactus RF60 is now an off-camera TTL flash with firmware version 205 or later!

    Metz M400 (for Fujifilm) is now supported on the Cactus V6 II (HSS and TTL).

    Nikon D750 users please read this thread: 

    Fujifilm EF-X500 users please read this thread:

    Feel free to suggest an improvement or share product ideas. Contact us directly at  At Cactus, we listen. 
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