Sony RX100 mk 2 - cant get ikelite strobe to fire underwater consistently

[BryanHart]

Hi there,
I have a Ikelite DS160 with a Ikelite Fibre Optic converter.
I have Nauticam housing
Camera is Sony RX100 mk 2.

I use the manual fill in flash of the Sony
Set it to its lowest power output.

I have a wee fine Fibre optic cable.

On land, test shots work fine.
Underwater - the strobe fires intermittent.
Deeper I go - no strobe firing?

I have noticed the Sony rx100 2 flash has a pulse light output, almost flickers ?
I have heard the Ikelite Fibre Optic sensor does not like that?

But what cant understand is how below 20m the strobe will not fire?

Please help me get this set up to work!

 

[Nemrod]

All Sony cameras (A series not sure) use a preflash for auto flash exposure, TTL, in all modes including Manual exposure. The preflash cannot be disabled. Your Ikelite strobe must be set to a preflash mode which is probably done at the controller.

Try turning the camera flash power back to (+) -0- (-) compensation as I assume you mean lowest power by going to a minus exposure setting for the camera flash?

 

[Rubidium777]

Different camera and housing, but I routed the fiber optic pick up to look right at the strobe window. Used clear silicone to hold it in place. The prior note about getting pre-flash set up is important.

 

[BryanHart]

All Sony cameras (A series not sure) use a preflash for auto flash exposure, TTL, in all modes including Manual exposure. The preflash cannot be disabled. Your Ikelite strobe must be set to a preflash mode which is probably done at the controller.

Try turning the camera flash power back to (+) -0- (-) compensation as I assume you mean lowest power by going to a minus exposure setting for the camera flash?

Thanks for this feedback. So as I understand it:
Even if the camera is in full Manual.
The internal flash will still fire that little pulse - and not just do a straight forward flash?

My Ikelite DS 161 has TTL mode.
But I want to shoot Manual with strobe

 

[Nemrod]

Thanks for this feedback. So as I understand it:
Even if the camera is in full Manual.
The internal flash will still fire that little pulse - and not just do a straight forward flash?

My Ikelite DS 161 has TTL mode.
But I want to shoot Manual with strobe

Yes, that is correct, your RX100 will always fire a preflash even with the camera set to Manual. You must set your Ikelite controller for preflash cancel. You can still shoot your strobe in manual, the strobe controller preflash cancel with fire the DS160 a single flash even though the RX is firing a preflash.

 

[BryanHart]

Yes, that is correct, your RX100 will always fire a preflash even with the camera set to Manual. You must set your Ikelite controller for preflash cancel. You can still shoot your strobe in manual, the strobe controller preflash cancel with fire the DS160 a single flash even though the RX is firing a preflash.

I have an Ikelite Fibre Optic converter and an " old" ikelite slave sensor - it is black and has the cable that fits into the strobe..
Are there other strobes that can handle the pre flash?

 

[Nemrod]

I have an Ikelite Fibre Optic converter and an " old" ikelite slave sensor - it is black and has the cable that fits into the strobe..
Are there other strobes that can handle the pre flash?

Yes, most modern strobes from Inon, YS, Sea and Sea, Retra, Backscatter, can all handle a preflash. The Ikelite strobes may not be able to with the controller you have, not sure. I avoid Ikelite like the Black Death, so not fully up to speed on their latest strobes and bread boxes.