Originally posted by jolepo After thinking about it and calculating the cost of the two options (Cactus or Godox), I think I have to change my option ...
In my case I have a flash Shanny SN600FGZ (P-TTL and HSS in the camera shoe) and a Yongnuo YN560 IV (powerful but totally manual). The Shanny flash fires separate from the camera with a P-TTL Meike PT-01 cable, retaining all TTL values. Yongnuo, as slave S2, shoots when he sees Shanny's light.
If I opt for the Cactus option, the best price I can find for 2 units of Cactus V6 II is about € 150. This would allow me to have Shanny flash (P-TTL and HSS) connected to a V6 and the other V6 to the camera. The Yongnuo can shoot as slave S2. Even if I want to use HSS (the Yongnuo does not have this option) I can simulate it by shooting this flash at the maximum power (1/1) in slave mode S2: taking advantage of the duration of the flame is 1 / 200s is sufficient to illuminate the photo without dark bands.
If I opt for the Godox option, the best price I can find for the new XPRO-P transmitter is € 70. Since I do not have any flash that is activated with the signal emitted by the XPRO-P from the camera, I should buy a Godox, for example the economic TT600 that is capable of responding to the wireless signal of the XPRO-P and has a good power and HSS. This flash I can find for € 70. So the total of the Godox option would be € 140. This would allow me to use the Godox flash (P-TTL and HSS) separated from the camera. The Yongnuo and the Shanny can be shot as slaves S2. Even if I want to use HSS (the Yongnuo does not have this option and the Shanny either when it's out of the camera) I can simulate it by firing these flashes at the maximum power (1/1) in slave mode S2: taking advantage of the length of Flame is 1 / 200s is enough to illuminate the photo without dark bands.
CONCLUSION: It is possible that, in my case, the best option is Godox, because it is cheaper and, in the event that I wanted to expand my lighting system with more flash drives, I could always buy the cheap Godox TT600 that brings the built-in Godox receiver.
After my publication, mcgregni, Class A and inkista have published a series of very clear opinions that open a scenario different from what I had planned.
Buying a single Cactus V6 II, placing it on the Pentax KP and stacking the P-TTL Meike PT-01 cable (which transfers all TTL information) on the V6 II, I can install the Shanny SN600FGZ flash on the other end of the P-TTL cable, thus retaining all P-TTL and HSS power of this flash.
The Cactus V6 II has a cost (in my country) of about € 95.
This configuration would allow the Shanny a bit separate from the camera (the distance that the cable allows) with all P-TTL and HSS power.
Additionally, the Yongnuo 560 IV flash (totally manual) I can use it in slave mode S2, as I said in my publication, with the option to simulate HiperSync / PowerSync by configuring it at the maximum power (1/1).
If it were necessary to separate the Shanny much more from the camera, the P-TTL Meike cable should be replaced by another Cactus V6 II, which would be placed at the base of the Shanny (which would retain all P-TTL and HSS power) . The cost, another € 95.
For a future enlargement of the lighting system, it would only be necessary to buy a Cactus RF60X that would receive the Cactus V6 II signal, installed in the camera's shoe. In my country, an RF60X costs about € 150.
mcgregni, CLass A and inkista, thank you very much for your posts!