[handlep]

Hi folks, I've also posted this on another forum, but someone may spot it here first. I'm hoping someone can clarify something for me. I just acquired a Metz 48 AF-1 to use with my K-3. Both devices have the latest firmware. I was playing with the wireless triggering function, switching between Master and Controller on the camera to see the difference. Now, everything I have read indicates the Controller option will not contribute to the exposure, whereas Master will. So I have taken shots in both modes, with the camera pointing towards a mirror. In both options, the built-in flash shows in the mirror, but strangely in the Controller shots, the built-in flash is significantly brighter than in the Master shots. I would have expected this to be the other way around if, in fact, the Controller option isn't supposed to contribute to the exposure.

Can anyone illuminate me please?

Thanks in advance for any help.

[pschlute]

Can anyone illuminate me please?

Nice pun

Take some images and check if it is working correctly.

When using optical triggering in P-TTL mode, the on-camera flash will be firing at least twice....once to trigger the slave to make a pre-flash; and once to trigger the slave to fire for the main flash. In Master mode it will be firing a third time to contribute to the flash output.

You are correct that in Controller mode it should not be contributing to the flash output. You should not be able to see this by looking in a mirror as the cameras mirror will be up at this point. It may be that in Controller mode the output is brighter for the first two functions, because it does not need to save any power for the main flash. Optical triggering depends on line of sight between the two units and in a bright ambient situation you want as much power from the controller flash as possible.

[UncleVanya]

There are many threads that suggest the controller feature doesn’t completely eliminate light contribution to the exposure - but I’ve never seen results suggesting it adds more than the master mode. Very interesting. Try some non mirror shots, perhaps the mirror reflecting the light is contributing to the issue somehow.

[stevebrot]

Can anyone illuminate me please?

Ditch the mirror. Chances are you have overwhelmed PTTL. If you need to gauge contribution, do it by comparing shadows cast at different angles from each flash.


Steve

[handlep]

Nice pun

Thank you, I was quite proud of that

Thanks for coming back to me. I will take a few shots under controlled (as much as possible) conditions, and post them here, but it may not be until tomorrow.

Thanks again.

@UncleVanya and @stevebrot, I'll try that also, thanks.

[handlep]

OK, so I have taken 4 pictures, 2 in a mirror, 2 to show shadow. Obviously composition, exposure etc was not relevant.


The first picture is taken in Master mode, second in Controller mode. Third is Master, fourth Controller. It seems obvious to me that the inbuilt flash is far brighter in the first picture, and the shadow is less defined in the fourth, indicating the inbuilt flash provided some fill light not present in the 3rd picture. Or, am I interpreting this completely wrong?

As always, all help gratefully received.