which setup to shoot burst underwater?

Hi folks,

I am seeing more and more situations where i would like to shoot bursts underwater, such as approaching schooling fishes, rapid swimming hunters, or macro.

So, i am looking for advice on which setup attributes to look for in order to make it possible, i have in mind a few areas of attention:

Strobe exposure control: TTL or manual

I know most of you probably go manual, but having tried both, i must admit i still prefer TTL, which gets the exposure quite right in most of my experience.

And when shooting actions, i doubt even further my ability to get manual exposure right.

I am just wondering if the extra flashes needed for the TTL may limit the ability to shoot multiple real flashes, or limit the burst frequency.

The answer might depend on the next point though.

Strobe connectivity: electric or optical fibers

Like many, i moved to optical fibers (got corroded electric cables twice...). It's great in terms of reliability, though it introduces a dependency on the camera's internal flash capabilities.

In manual mode, you workaround it by setting the internal flash to 1/64th of it's power or something like that.

When doing so, are we confident the internal flash won't be the limiting factor?

So bottom line questions: are optical fibers a no-go for burst shooting?

Or OK... in manual only?

Which strobes?

Some strobes might be more capable than others in terms of burst shooting. Right now i use two Inon Z240 type IV, would there be suitable? Would others be better?

I must say i am puzzled by the userguide's recommendation to limit the number of shots, wait for the strobe to cool down, etc...

Camera continuous-autofocus capabilities (underwater)

Though burst mode could be used for still subjects to capture a given attitude, i foresee it mostly for fast moving subjects. Hence, there's a need for good continuous focus capability on the camera side.

I am currently using an Olympus Micro 4/3 and i don't think these cameras are (yet?) fit for continuous autofocus.

Before i used Nikon, and would not be against going back to this brand. So question is which of their D-SLRs would do the trick - not sure the D7000 is sufficient? Or maybe it is?

Something to add: i would really prefer to avoid full frames cameras, i could cope with the budget of an APS-C D-SLR, especially if i can buy it used, but full frame would be too expensive and bulky for travel (already have to carry 2 rebreathers, for wifey and myself...).

Any other criteria to consider for that setup?

thanks in advance for sharing your thoughts :-)

cheers

Nicolas

The inon guys aren't kidding about "limit the number of flashes". If you shoot at high speed or full power (and especially if both) you will overheat and burn out the flash tubes. This will initially reduce the available light output. Eventually you get all the way to zero with completely brown tubes. The capacitor will still charge and discharge but the flash tubes are no longer viable. How long this takes depends on the temperature of the water and your shooting behaviour.

The bigger bodied strobes may be better able to absorb the heat created by the flash tube. I have used burst mode successfully with a Canon speedlite on land, and with natural light no strobes underwater (split shots in waves, zippy sealions - close to the surface and both with manual focus).

hi errbrr,

thanks for this feedback, looks like the Inons aren't fit for burst shooting then

Or i'd have to ensure i am not at full power, maybe by increasing the ISOs

Waiting for other comments on that

cheers

I belive that other brands of strobes, especially the ones with a plastic housing will have the same problem of overheating strobe tubes.

The same problem can occur using a housed land strobe as it can^t dissipate the heat generated by the strobe tubes.
Subtronic claims that their Pro270 strobe can handle fast strobe flashes (but this may related to fast strobe recharge)
http://www.subtronic.de/productView.php?product=Pro270%20ohne%20Zubehoer
You may write them a email to verify that.

Chris

I have shot higher speed bursts underwater. I used my 5dmk3 shooting at 6fps with the YS-D1's. By default, as the 5dmk3 does not have a pop up flash, I used electrical sync cords. I used this set up mainly for mandarin fish or anemone fish shots. Using the D1's at 1 click under half power, sometimes even 2 clicks. I find I can fire around a 2 second burst with the D1's. I don't do this often and do let the strobes cool down. Most of the time the burst is for 6-8 shots.

Optical triggering by the factory popup flash won't usually work even if you manually set the flash to low power as (in Canon's case) the body limits to 3fps. If you want optical triggering then you'll need some sort of converter from electrical to optical, like the one found on S&S housings, I believe this setup will also do TTL, but I don't have first hand experience.

cheers

S.

hi errbrr,

thanks for this feedback, looks like the Inons aren't fit for burst shooting then

Or i'd have to ensure i am not at full power, maybe by increasing the ISOs

Waiting for other comments on that

 

cheers

In tropical water with lots of sunlight the challenge is not having too little light but too much light. Boosting ISO affects strobe and sunlight the same and needs to be compensated by closing the aperture to avoid overexposure. So it doesn't really help. Best to use the shortest possible shutter time because that cuts down sunlight allowing you to open the aperture and capture your precious strobe output more efficiently. Of course if you are relatively shallow natural light with/without magic filter will solve the problem.

Bart

Thanks for the comments guys.

@Stewart, i guess 5 fps would be the maximum i would be looking at, good to know the YS-D1 coule handle it with the settings you mentioned.

Interesting comment on the eletrical to optical converter, i think Nauticam also produce some.

Nicolas

 

In tropical water with lots of sunlight the challenge is not having too little light but too much light. Boosting ISO affects strobe and sunlight the same and needs to be compensated by closing the aperture to avoid overexposure. So it doesn't really help. Best to use the shortest possible shutter time because that cuts down sunlight allowing you to open the aperture and capture your precious strobe output more efficiently. Of course if you are relatively shallow natural light with/without magic filter will solve the problem.

 

Bart

Indeed Bart i've experienced it yesterday when the background became waaaay too clear behind my barracudas...