[MSL]

When using the Pentax Hot Shoe Adapter F and Off Camera Adapter F with a long connection cable is there any limit on using two flashes at once? Do they have to be matching flashes, or have near matching trigger voltages (aside from being below the 12 V threshold)?

[Marktax]

You can mix and trigger by cable any number of Pentax-compatible flashes as long as they are the same type -- P-TTL is the best mode for the modern bodies.

[Tanzer]

That's a question I've asked myself. If you put 12 volts across 3 volts, what do you get? Well it depends on the impedances and other electrical characteristics of course. Unless I knew the flash had circuitry to protect this configuration, It does not sound like a good idea so I have given up on the idea of wiring all my flashes in parallel. Optical or RF triggers have some advantages in their own right to be sure, but for me, it is more a case of there not being any wired solution that I am comfortable with.

[Class A]

No equipment manufacturer (e.g., for radio triggers) I am aware of, officially recommends triggering two flashes through one electrical connection.

People often want to fire two or more flashes as a pack with just one trigger and use Y-splitting cables or similar for that but one should not overlook the complications that can arise from using flashes with vastly differing trigger voltages.

One manufacturer said an electrical connection between two flashes is OK as long as the voltage difference is small, but I forgot how large the difference was and IIRC it may have been in the context of high voltage flashes. The tolerable voltage difference maybe smaller or bigger for modern, low-voltages flashes.

[wombat2go]

The ist ds manual page 158 shows how to cascade using multiple adaptors F/ & cables from the camera.

The types of flash that can be paralleled are combos of {AF360FGZ, AF500FTZ, AF330FTZ}
or {AF400FTZ, AF240FT}