Cactus V6 II and Nikon SB-800 with Nikon D750

I am also having trouble getting the POWER LEVEL to change in my Nikon SB 800 flash via the Cactus units(flash set up TTL for this) , unless I go the flash on the light stand and adjust power on the flash unit(I set the SB800 is set to manual for this). I am having NO issues with the TX triggering the flash on the RX unit, regardless of whether or not the SB 800 flash is set to TTL or Manual.
Help Needed: I would like to be able to adjust my SB800 power level using the TX/RX transmitters and not have to go to the light stand, lower the light stand to my height so I can read the input screen and manually change the power level. I have seen the questions asked several times in the forum and have tried to follow any relevant suggestions. I have reviewed my Cactus manual several times as well.
Here are the facts so far:
Software NIK.A.005 on both RX/TX units.
All profiles on RX/TX Cactus units are recognizing the SB 800 profile
Flash Nikon SB 800
Camera used . Nikon D750
Setting under Function Menu on TX unit-On camera TTL-set to OFF ( I don't know if this is relevant or not)

It appears that when I change the zoom on the TX unit the RX is adjusting the zoom level on the flash. At least the flash is making some sounds and the LCD on the flash unit is changing to whatever zoom mm I am dialing in.
On page 83, under section 19 of the cactus manual on the LED Signal Guide Chart it refers to an orange light on the RX unit when changing the power level on the TX unit. I am getting this orange light when changing the power level on the TX unit
I have done many test shots with different power levels being selected with the TX unit, with the flash in the TTL mode as explained in other discussions, but the power level is not changing.


  • meubel said:

    (I set the SB800 is set to manual for this).

    Please select TTL mode on your SB800. The Cactus transmitter manipulates the manual power in the TTL mode of the Nikon flashes.

  • I do set flash to TTL, see first sentence above in my comment. It does not change power level of flash via Cactus. Therefore, I then set to manual on flash ( also in the first sentence) so that I can adjust power manually on the flash itself. This is what I am trying to avoid, to go back and forth to the light stand and adjust power level on flash unit.
  • In this case, the connection between the V6 II and the SB-800 may not be good, since you need all the small pins of the flash to get contact with the V6 II to transfer the power level info.

    Please do a small check with the set up.

    On the RX that connects to the SB-800, set the FLASH SYSTEM to AUTO. Then switch off the V6 II. When you switch on the V6 II again, it will auto detect the flash system. If it successfully detects the SB-800, it will show an "N" inside the flash icon on the V6 II LCD panel. That means the V6 II knows that it is a Nikon flash. In that case, the connection between the flash and the receiver is said to be OK.

    If not, please check whether any of the hot shoe pin on the flash or on the receivers is not in good form (for example oxidized, or blocked by some dirt, etc.). Also, please check that the flash has been fully inserted and locked to the receiver. That would give us some hints about the type of issue in your setup.

    Thanks for your follow up.
  • The step above was done per your instructions. The N appeareared inside the flash icon. What should I try next? The flash fires just fine, just no power level changes happening using the TX. Again, changing the power level on the TX also registers the same change on the RX LCD panel. The power level on the actual flash just doesn't change.
    Thanks for your help and continued advice.

  • One more check with your connection between your camera and the TX. In X-TTL for Nikon, you do not have to detect the camera. However, the auto-detection also serve as a check of the connection status.

    In NIK.A.005, once connected with your camera, please try switching the shutter speed. If the connection status is good, you should be able to see the newly detected shutter speed on the V6 II TX screen.

    If the connection status is not good, your SB-800 will keep making full-power only. It is because it does not receive all the info necessary to give a correct exposure from the V6 II TX.

    Please check and see if this is the case.
  • This seemed to work. :) The issue seems to be if the TX is not set exactly in the right place on the Nikon D750 the pins are not aligning and thus not communicating all the information. I took the TX off, put it back on gently and then when I moved the ISO, SS, or Aperture all those changes were reflecting in the LCD screen of the V6. Then I tested by shooting an image and changing power on the TX to see if the flash power would change. Yes, it worked! From now on, as I take the TX off and on, I will make sure that it is correctly aligned on the D750, test the SS/ ISO readings to make sure the TX LCD screen is registering those settings to ensure I set it on properly. The alignment shouldn't be this touchy as it slides in pretty easily on the Nikon flash mount, but it is.
    Thanks for your help and I hope other SB800 or Nikon 750 users can learn from your support comments.
  • Great to learn. Thanks.

    The D750 hot shoe is a bit different from the usual Nikon hot shoe. Some care is needed when aligning it with the transmitter's hot shoe.

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