Can't get TTL to work with RF60 and V6II on a Nikon D700

BNB

Hello! Thanks for looking at my question.

With the V6II on my Nikon D700 and an off-camera RF60, I can't get TTL to work.

I have one Cactus RF60 flash off camera, in Slave mode, showing 'TTL' and the TTL compensation on its display.
The V6II trigger shows the TTL icon next to the correct flash group.
'Camera info' is on and works, showing all updates to the camera settings as I make them.

Using the depth-of-field button on the D700 triggers a (pre)flash.
The D700's info screen shows the hotshoe 'flash' (V6II) is in 'commander mode', no TTL icon there. Should there be?

So, when shooting, yes, the RF60 fires. But:
The flash output is not automatically balanced for a proper exposure.
Shooting a frame at a close object and another further away, both result in the same flash output (and overexposed close object, underexposed far-away object). The same with a dark object vs a light one.

Strangely, flash compensation using the V6II works somewhat. The flash power output changes, but not in proper ratio to the selected compensation.

Settings on the V6II;
at bootup:
"Det. Flash: (others symbol)"
"Cam System: (nikon symbol)"

Camera System: Nikon
Flash System: Auto
Flash Mode: TTL Only

I'd appreciate any help with this.

BNB

Oops, I forgot the firmware versions!
V6II : NIK.A.003
RF60 : A06

raychan

Hello @BNB

It looks like the firmware that you have loaded into the V6 II is correct. We have the same gears here that works as expected.

You might try factory rest on the RF60 and V6 II to see whether it works again. To do that,

RF60 : press and hold the + and NEXT button while switching the power to ON from OFF
V6 II: go to MENU, PREFERENCE, FACTORY RESET

My second though, it might be hardware issue. If you have another RF60 to test, that will be helpful to find out the problem.

I hope that helps.

BNB

Hi Raychan. Thanks for the quick reply!
I did the reset of both the RF60 and V6II. Same results.

And I haven't got another RF60 to test.

But I did test this situation with another camera (Fujifilm X-T1) and another V6II (with Fujifilm A.002 firmware) with exactly the same results. 'Camera info' works, the preflash fires, the main flash fires, but the power output is always the same no matter if the camera is pointed to a dark subject vs a light subject. TTL Flash compensation does have an effect on the power of the main flash. But it is not linked to the subject, as I would expect with TTL measurement.

Anything else I can try?

raychan

@BNB

There is something you can check.
1. make sure the RED EYE REMOVAL in the camera menu is disable. Usually, it's under flash setup;
2. deactivate POWER SYNC in the V6 II menu under FUNCTION;
3. keep the RF60 and V6 II at least 1 meter away from each other, because the radio signal maybe too strong in short range and cause misfire.

Let's see how it works.

All the best,

BNB

Hello @raychan, all is well !!
I did some more experimenting and I discovered that I was hitting the low limit of the flash power. Therefore it seemed as if the flash power was not always adequately adjusting to my changing f-stop.

Duh

This leads to a suggestion - as the V6II calculates the correct power level and knows the possible power settings of the used flash (minimum 1/128 or 1/256 or whatever) then it could issue a warning after the calculations resulted in a correct power of 1/512 (for example) and likewise if the correct power would have to be 2/1 (double the max power). A message on the screen like "1EV MORE REQUIRED" or "2EV LESS REQUIRED" would help the photographer at knowing what causes the under/overexposure.

Thanks so much for your help and very fast responses. I'm even more happy to be a Cactus customer now :-)
Keep up the good work!

raychan

Thank you @BNB

I'm pleased to see it works for you.

Cheers!