Cactus V2 Help

chrisburke · Jan 16, 2009

well my v2's arrived today... (one transmitter, 2 receivers) they really dont come with any kind of user manual... and there really isn't a whole lot online about them... so i guess i'm hoping someone here has them and knows enough about them...

i'm testing with one flash right now, because the batteries are dead in mu nikon strobe so I'm using the sunpak...

batteries are in... i press the test button on the transmitter.. light flashes on the transmitter and the receiver.. which tells me they are communicating fine.. so I slap the flash on the receiver, the transmitter on my camera, adjust settings, fire... light flashes on the transmitter, light flashes on the receiver... but the flash doesnt go off...

anyone know what the issue might be?

dEARlEADER · Jan 16, 2009

Have you test fired the flash without the trigger?

chrisburke · Jan 16, 2009

yup, it shoots fine... i wait for the light on the back of the flash to tell me its ready... press the test button (on the flash) it works fine and dandy... but when i put it on the cactus, and hit the button the the transmitter, the indicator lights on the transmitter and receiver flash, but the flash doesnt go off

dEARlEADER · Jan 16, 2009

Is the transmitter and receiver sharing the same frequency?

edit: try the other receiver

chrisburke · Jan 16, 2009

yea they are.. i'll try the other one...

same thing.. red light blinks on both trans and receiver.. but no flash....

have you read anything about a compatibility issue between them and the sunpak pf30x??

frXnz kafka · Jan 16, 2009

Are they the V2 or V2s model? And what is the trigger voltage on your flash?

If you have a volt meter, test the receiver to make sure the circuit is closing properly when it's triggered. You could also try using the PC connector instead of the hot-shoe, or vice-versa.

If all else fails, get some batteries in your other strobe and try that.

chrisburke · Jan 16, 2009

just the v2... no idea of the voltage of my sunpak... and no voltage meter...

sunpak doesnt have pc connector... guess i'll have to wait until tomorrow and get some batteries for my nikon strobe

chrisburke · Jan 17, 2009

OK... I tried the Nikon flash.. it works fine... so I looked over the connectors on the bottom of both flashes, they are identical...

except one has a metal plate and the other doesnt... i'm wondering if maybe the sunpack just isn't connecting to the metal.... is there something I can put in there to ensure its connecting... if I recall back to grade school, tinfoil lets electricity travel through it.. can I just put a small piece of that in there so that I can be sure that all the connectors are touching them metal, or will that fry it??? any electricians out there ??

Katier · Jan 17, 2009

The Cactus is 'just' a trigger right? i.e. it's only using the center contact and the hotshoe (no TTL or anything).

The Sunpak works ok directly on the camera in manual mode I assume?

I would take a look that the hotshoe is making contact ok, I believe the circuit that your interested in is the center contact and the 'spring' contacts that sit in the groove either side of the flash shoe. Try to see if they appear to be in contact properly.

Not sure what the metal plate is but as long as part of the flash's shoe ( or the afformentioned spring contacts ) is in contact with the metal of the cactus reciever it ought to work.

chrisburke · Jan 17, 2009

is there a way I can tell that its touching the contact properly.. i mean, its not see through... and in the event that its not, how can I make it.. which is why i mentioned the tin foil (which is a conductor) can i just put it between the cactus and the flash to make them touch??

Katier · Jan 17, 2009

What I would do is us a pin. Put it in the groove on the flash shoe and carefully put the cactus on. (do this at own risk

) - foil may not work as it would probably get torn.

chrisburke · Jan 17, 2009

so i tried something else out... i hooked my WIRED slave (nikon sc29) into the cactus receiver.. and my sunpak into the other end... still no dice... it worked fine that way with my nikon flash, but not the sunpak... i'm very confused as to why this is not working...

DeadEye · Jan 17, 2009

Chris its likely a contact closure time problem. I use wizards and have the same problem with an old vivitar flash. The flash works perfect on the old vintage film camera with its dry contact closure. WILL NOT WORK with a standard out of box wizard. The transistor switch goes to ground when its time to flash but only for a few milliseconds. This works well with modern flash units, but some older units need a few more milliseconds to discharge the trigger capacitor that ionizes the gas the the flash tube thus discharging the main storage capacitor and getting the light you desire. With a MULTI MAX trigger you can custom set the closure time and use it as the receiver. This will not help your case but hope it gives you insight. Garbs could prob explain it better.

Katier · Jan 17, 2009

DeadEye said:
Chris its likely a contact closure time problem. I use wizards and have the same problem with an old vivitar flash. The flash works perfect on the old vintage film camera with its dry contact closure. WILL NOT WORK with a standard out of box wizard. The transistor switch goes to ground when its time to flash but only for a few milliseconds. This works well with modern flash units, but some older units need a few more milliseconds to discharge the trigger capacitor that ionizes the gas the the flash tube thus discharging the main storage capacitor and getting the light you desire. With a MULTI MAX trigger you can custom set the closure time and use it as the receiver. This will not help your case but hope it gives you insight. Garbs could prob explain it better.

That makes a LOT of sense. I think in that situation I'd run the old flash off a PC connection and the newer flash off the cactus.

chrisburke · Jan 17, 2009

i totally understand what your saying.. but this isnt an old flash... its got focus sensors and everything in it.. i bought it bran new from the camera shop... maybe its not as new a unit as i thought???

I found someone in my town who is sell the same flash as my other (nikon sb50dx) so I'm waiting to hear from him and I'll just buy that one and maybe put the sunpak on a optical slave or something....