TTL with Olympus and YS-D1/2... Wasting my time?

I dive infrequently because I am landlocked, but every time I do get wet I try to improve my UW photo skills.  My current rig is an Olympus E-M10 MKII in a Nauticam housing with one Sea & Sea YS-D1 and one YS-D2 that was purchased later.

I have tried S-TTL in the past with the YS-D1 with mixed (more bad than good) results.  Eventually I settled on firing the strobes in manual.  This is more reliable, but I still miss some shots if I change the distance to my subject and don't properly compensate.

A few years ago I added a 2nd strobe, a Sea & Sea YS-D2.  Probably a stupid move when I wasn't completely happy with the YS-D1, but I was at least comfortable with the controls and the performance when it worked.  When I purchased I was thinking of manual operation, and in that regard the YS-D1/2 strobes work well.

Recently I've been doing some experiments on dry land to see if I would have better luck using TTL and the YS-D2's "Custom" mode.  I'll cut to the chase and say no, I didn't.  After setting the strobe to custom mode B, the one that it supposed to work with my camera, I tried some shots using both TTL modes and the Fill flash mode on my camera.  Taking the exact same photo, not moving a thing, and waiting for the strobe ready signal, I got shots that were basically black, completely blown out, and well exposed. I don't understand how the system can be so unreliable.  Consistently low or high would be easy to compensate for, all over the map just doesn't work.  It's not the camera as the TTL system of the camera alone is fine.  Even with the modest built-in flash, I get virtually the same exposure across the aperture range although it does drop off at f20 where the flash lacks the oomph for such a small aperture.

My experiments were with just the YS-D2.  Given the similar unreliable operation of the YS-D1 on S-TTL, I would hardly ever get them both to work correctly at the same time.

I can't afford to change strobes our housing at this time so I have to live with what I have.  Am I wasting my time messing with TTL for these strobes and my Olympus?  Is there something that I'm missing?

If someone has figured out the secret to make Olympus and Sea & Sea play nice together I sure would like to hear how you did it.

Thanks

The one thing you have not mentioned is the fibre optic cables - the YS-D* strobes are well known for being picky about cables - they need very good transmission characteristics for TTL to be reliable, the gold standard is 613 core cables from either S&S or Nauticam.  They will fire in manual but not necessarily in TTL or if they do reliability is poor as you report.  Do the strobes fire reliably in manual  - like 99-100% of the time?

Underwater does change things and it seems some cameras do good TTL UW and others don't - but your experiments are on dry land.  Was your previous UW TTL experience on wide angle or macro?  Traditionally macro was easier to get TTL that was reliable compared to wide angle.

Having said all of that I tried TTL a few times for macro on my Olympus/INON setup - would have been on the EM-5 II and quickly reverted back to manual and have stayed that way even after upgrading to the EM-1 II.

When I went digital wit an Olympus E-M5 in a Nauticam housing and my two trusty Inon Z240 strobes I was completely disappointed by the strobe exposure results (Macro / TTL) - mostly under-, but sometimes completely overexposed. Manual was never a problem.

I had spent a lot of money on the equipment - except for the fiber optic cables, they were a cheap no-name brand. And exactly those cables were the problem. Can't remeber if it was here or in another forum where a fellow photographer recommended the use of multicore Sea&Sea cables.

And bingo! - No more problems since I used these cables. They also reliably work with my YS-110a and both my Inon S2000 backup strobes. No experience with the YS-D series.

I think it was this guy who told me that not only some strobes, but also the Olympus TTL protocol (at least on an E-M5) is very picky...

Maybe you can borrow a high quality cable from a friend and test it with your before buying?

Hope this helps.

Thanks both for your thoughts.

One of my cables is genuine sea & sea, but I'm not sure about the other.  The other is a bit thinner and has a tighter spiral.  I tried it with both cables and got unreliable results with both.  Maybe my "good" cable has some broken fibers.  It doesn't look kinked or anything to suggest damage but who knows.  Maybe I'll splurge on a new cable.

As far as manual triggering goes, it seems to be very reliable if you don't count the times I forget to let the strobes recycle.

Interestingly, while window shopping cables I noticed that one of the photos for a Sea & Sea brand cable was a promotional drawing of the "New" multi-core fiber cable.  This could be really old promotional material, but if it is relatively new tech then my cable might not be multi-core.  I bought the first cable when I bought the YS-D1 8 or 9 years ago and the second a few years after that.

If I can't get TTL to work, I'll just keep practicing my manual shooting.  It was only a few dive trips ago that I started shooting the camera in full manual, and that in itself was a game changer.  Mastering the strobes is just one more piece to the puzzle.

I have  one D1 and and two D2 strobes. However I only ever use manual and they have all been very reliable. It is generally thought from all me findings  manual is best any way. Two strobes are often on different powers anyway. personally I cant see myself ever using TTL. But that's just me.

Best of luck with playing with manual settings. PS if you are doing any wide angle and balancing existing light you will be using manual anyway.