[Barbarosa]

cactus v5 have shoe for flash so is it possible to use radio flash master transmitter and gps unit for geotaging.
example, when shot on the field macros and wildlife on bait, like fox on peace of meat, with prepared masked flashes, we use radio transmitter for range, so is it possible to attach gps unit on wireless transmitter and do geotaging automatically.

[adr1an]

I'm pretty confident no - as the GPS will be using the TTL/Digital Pin on the hotshoe. As Cactus' dont work with pTTL remotely, then they wont work with the GPS either in a remote setup.

The ttl pass-through on-camera should work fine though - assuming that works with cactus' ?

I'm just guessing based on the only way I can see them having the GPS talk via the hot-shoe... hence the need for FW upgrade to also cater for some sort of new comms protocol to the GPS... or at least make it understand encapsulating the NMEA statements and most likely Gyro/Compass data on a TTL message... Don't know enough about the pTTL protocol to know if its just that or uses a new protocol after identifying to the Firmware that its the GPS unit via the Mode pin or something...

The above could also mean it wont work piggy backed onto an on-shoe Cactus, unless it mimics the pTTL stuff or at least passes through all the pins unmolested ? I use RF602's so it wont work anyway so havent coveted such abilities...

[Barbarosa]

im just interested in passthrough, not to install gps on remote flash just on master transmitter on camera.
So if that way can work that would be great.

[enoeske]

I don't believe the cactus v5's do p-ttl passthrough on the hotshoe. I think they just have a regular fire signal passthrough. The GPS module will not work on top of a cactus v5.

[Steinback]

You are looking to use the new Pentax GPS unit?

It should be possible to build something that will work using the Pentax F hot shoe adapter system components (or one of the 3rd party knock offs). You can build a set that will give you an on camera adapter with P-TTL pass through, a remote cord, and a second off camera hot shoe that is P-TTL capable. I expect that you would then be able to run your GPS unit and your Cactus trigger at the same time.

Depending on which camera body your have, it should also be possible to run the GPS unit off of the hot shoe on the camera and trigger the Cactus using the PC port on the body.

Pentax Hot Shoe Adapter F 31022 B&H Photo Video

pentax flash cord