Sea&Sea YS-D3 doesn't work with UWT TTL trigger?

19 minutes ago, ChrisRoss said:

 Bluewater seems to really like the S&S strobes for some reason - just an impression I have.

I think the statistic that is missing from most websites comparing strobes is the % profit that the sales of a certain model offers dealers... 

Alex

Thanks, guys. Just wanted to give an update about my issue.

1. I primed 2 of these random 613 cables and they didn't work with my YS-D2: https://www.amazon.com/DIVTEK-Underwater-Diving-Photography-Coiled/dp/B07FSGKW5S/ref=sr_1_3?dchild=1&keywords=613+fiber+optic+cable&qid=1613672246&sr=8-3

2. One annoying shipment delay later, I ended up having Backscatter 2-day their 613 cable to Oahu. It works with my YS-D2 only in the left port! So if I upgrade my 110-A to something newer, I'm guessing it wouldn't fire if the 613 cable is plugged into the right port either? It's frustrating, but I'm going to contact Aquatica to see if maybe the problem is with their flash trigger.

7 minutes ago, sharkadobo said:

Thanks, guys. Just wanted to give an update about my issue.

1. I primed 2 of these random 613 cables and they didn't work with my YS-D2: https://www.amazon.com/DIVTEK-Underwater-Diving-Photography-Coiled/dp/B07FSGKW5S/ref=sr_1_3?dchild=1&keywords=613+fiber+optic+cable&qid=1613672246&sr=8-3

2. One annoying shipment delay later, I ended up having Backscatter 2-day their 613 cable to Oahu. It works with my YS-D2 only in the left port! So if I upgrade my 110-A to something newer, I'm guessing it wouldn't fire if the 613 cable is plugged into the right port either? It's frustrating, but I'm going to contact Aquatica to see if maybe the problem is with their flash trigger.

Based on another recent thread, I have to ask... Have you tried cleaning the LED trigger ports on your housing, inside and out?

21 minutes ago, stuartv said:

Based on another recent thread, I have to ask... Have you tried cleaning the LED trigger ports on your housing, inside and out?

LOL, worth doing!

38 minutes ago, stuartv said:

Based on another recent thread, I have to ask... Have you tried cleaning the LED trigger ports on your housing, inside and out?

My housing was brand new when I did all the suggested tests above. 

12 minutes ago, sharkadobo said:

My housing was brand new when I did all the suggested tests above. 

It does seem unlikely that they would need it. OTOH, it also seems unlikely that your D2 would work when connected to one port but not the other. Cleaning is free and easy...

3 hours ago, stuartv said:

It does seem unlikely that they would need it. OTOH, it also seems unlikely that your D2 would work when connected to one port but not the other. Cleaning is free and easy...

Hmmm, if cleaning that right port doesn't do the trick and, assuming you have used the same cable/strobe to try each port, then that would suggest it has to be the right hand LED on the trigger. 

42 minutes ago, TimG said:

Hmmm, if cleaning that right port doesn't do the trick and, assuming you have used the same cable/strobe to try each port, then that would suggest it has to be the right hand LED on the trigger. 

Possibly an alignment issue - the port needs to sit right over the optical centre of the LED. 

If the YS-110 triggers on the right port - it suggests strobes other than the D2 and other known problem strobes  should also trigger there. so for example the INON strobes I expect would trigger just fine.

On 2/18/2021 at 2:10 PM, stuartv said:

Based on another recent thread, I have to ask... Have you tried cleaning the LED trigger ports on your housing, inside and out?

Right?!? ; )

On 2/18/2021 at 2:02 PM, sharkadobo said:

Thanks, guys. Just wanted to give an update about my issue.

1. I primed 2 of these random 613 cables and they didn't work with my YS-D2: https://www.amazon.com/DIVTEK-Underwater-Diving-Photography-Coiled/dp/B07FSGKW5S/ref=sr_1_3?dchild=1&keywords=613+fiber+optic+cable&qid=1613672246&sr=8-3

2. One annoying shipment delay later, I ended up having Backscatter 2-day their 613 cable to Oahu. It works with my YS-D2 only in the left port! So if I upgrade my 110-A to something newer, I'm guessing it wouldn't fire if the 613 cable is plugged into the right port either? It's frustrating, but I'm going to contact Aquatica to see if maybe the problem is with their flash trigger.

I bought one of these to try. Didn't work at all. Headed back to Amazon. 

I've spent the last few days profiling the YS-D3s with my custom TTL trigger board, on my Sony a7RIII.

Yes, they're frustratingly less sensitive, even though I'm using the brightest Cree red LEDs on the market (C503B), overdriven to give ~88000 mcd output.

• My YS-D1, YS-D2, and YS-D2J all trigger just fine with a minimum pulse length of 23 usec.  I can get 7+ stops of linear TTL response out of them.
• The Retras I tried last year would trigger with a minimum pulse length of 1 usec.
• I can trigger my YS-D3 with a minimum pulse length of 60-70 usec... about 95% of the time.
• Even with longer pulses, the YS-D3 will fail to fire every once in a while.  I'll get a preflash pulse, but not a main pulse.

I finally managed to get a working profile today, but to keep the LED pulses short enough I have to use TTL+1.0EV.  That gives a working range of 1/1...1/32, but still has the reliability problem.  At least when it fails to fire, it's still charged and I can take another shot.

With the LED shoved directly in the YS-D3 sync port, it gets enough light to fire even at a 10 usec pulse.  And that's bright enough to work with TTL (vs. DS-TTL) too, which would let me use the whole range of the strobe.  But getting power to that LED underwater is going to be a bit of a problem. 

And if I'm going to run actual wires, I might as well just get a bulkhead and modify my trigger board to do electrical TTL.

But the burst mode is phenomenal.  I can shoot 6 fps at 1/16 power (10 shots), 1/8 power (6 shots), or 1/4 power (3 shots).  That's going to be a huge help for black water dives, where it's hard to keep critters in focus.  Short, controlled bursts...

Oh, even more fun: One of my YS-D3s has already failed.  It won't fire with either my RX100 or trigger board anymore.  When I turn it on, the focus light flickers randomly, and the strobe tubes crackle with lightning.  Which I guess is how the YS-D3 gets its name.

Great info @Randall Spangler! Thank you for sharing it.

Can i Just check that I am understanding this correctly?

The Retras trigger with a 1usec pulse

YS-D1/2 series require a 23 usec pulse 

YS-D3 is needing at least 60-70 usec pulse

Please forgive my ignorance, but at what value does TTL cease to work?

I am sorry to hear that you have had a problem too. Please let us all know how you get on with this too.

Thank you again.

Adam

Super info, Randall. Thanks!

So, here's some more details on triggering.

In manual (or preflash cancel) mode, all that matters is that the strobe sees one (or two) pulses.  Try triggering at successively shorter pulses until the strobe doesn't trigger.  Do that with the strobe on 1/16 power or less, so you don't overheat it.  (Something that should be harder for YS-D3 than YS-D2; I've blown up several of those...)  With the bright LED of my trigger board going through one of the nice thick Sea&Sea cables, Retra triggers with basically the shortest pulse I can send.  YS-D2J (and D2, and D1) trigger with 4 us.  YS-D3 won't even detect a pulse less than 35 us or so.  If I shove the LED straight in the YS-D3 sync port, I can trigger it down to 5 us.

In TTL mode, the strobe actually has to measure the duration of the pulse.  The photodiode circuit takes a little time to saturate and turn on its output, so the input-pulse-to-output-power curve has a bit of an offset to it.  The strobe then takes that pulse length, and puts it through a lookup table to decide its output flash power.  DS-TTL works by shifting the table up and down based on the power dial.

YS-D2 interprets a 23 us pulse as 1/256 power.  Sometimes I can get it to fire at 1/512 - 1/1024 if I use a 20 us pulse, but it isn't reliable.  55 us = 1/32; 144 us = 1/8; 706 us = 1/2.  Anything longer than 2400 us will dump the entire flash. 

Note that these numbers are roughly logarithmic, because the strobe is designed to capture the output of a xenon tube.  These tubes reach maximum brightness very quickly, and so flash power is just controlled by duration.  Doubling the output requires double the duration.

Retra interprets 22 us as 1/32 power; 60 us as 1/8; 115 us as 1/2, and anything over 230 us as full power.  That's why every time a new strobe model comes out, we have to profile the strobe to determine what pulse length will cause the strobe to fire at what power.

Now, on to the YS-D3. 

In TTL mode, it can't reliably capture pulses through my sync cable shorter than 70 us.  If I use shorter pulses, it *sometimes* will fire a dimmer flash.  But most of the time, it doesn't fire anything. 

It also needs a much longer pulse to reach higher flash power.  Even a 940 us trigger pulse only causes it to fire at slightly more than 1/4 power.  Which is a problem, because the strobe needs to capture the *entire* pulse length before it starts firing its own flash.  If you want to use 1/250 shutter (which I do, on my a7RIII), the delay before the strobe fires means that the shutter starts closing before the end of the flash, and I end up with a black band on the top of my images.  So longer than about 1000 us trigger pulses can only be used at 1/200 sec.  Or 1/160 sec, if you need longer than 2000 us.

So, I turn the DS-TTL adjust knob up to +1.0.  Now a 940 us trigger pulse will fire a 1/1 - 0.7EV power flash, 1050 us will fire 1/1 - 0.3EV (still usable at 1/250 sec), and 1200 us will fire the strobe at full power.

But by shifting the table up using DS-TTL +1.0EV, I lose some of the bottom end.  112 us = 1/8 power, 72 us = 1/16 power, and 50-60us = 1/32 power, but fails to trigger a lot more often than I'd like.

On top of that, sometimes the strobe doesn't trigger at all, even when I'm using 200 us pulses for both preflash and main flash.

I'm really not sure what's going on at Sea&Sea to ship a strobe with such problems being triggered by LED boards - mine, Pavel's, etc.

The whole point of having a fast cycle time in the strobe is to be able to fire shots quickly.  And the only way to do that is with LED or electrical sync.  Triggering with a small strobe in a P&S camera means waiting for that strobe to recharge, which takes 3-5 sec.  Pretty much any external strobe will beat that.  (Which is also why the YS-D2 overheating problems aren't really a problem with P&S cameras; you just can't drive the strobe hard enough fast enough to melt it.  But with a LED trigger, you can...)

The DS-TTL implementation in the YS-D2J is remarkably solid and extremely reliable, and basically unchanged from YS-D1 a decade ago.  So I don't know why they would have changed that part of the strobe circuitry.

I'm really starting to wonder if Sea&Sea got a bad batch of photosensors, or put the wrong reel of some other component in the pick-and-place machine.  I can't imagine they'd design a high-end strobe that can't be used in TTL with high-end cameras with LED trigger boards.  But then why wasn't this discovered in QA testing before the strobes were shipped?

My hope right now is that I need to RMA my one YS-D3 which has already failed (!).  Sea&Sea has always been good about sending replacements.  And maybe the replacement will behave differently, showing that the initial production run really did have some defect they've since fixed.  In which case, I'll RMA the other one.

Otherwise, I'll end up using the YS-D3s with my RX100, and stick with my YS-D2Js for my a7RIII.

And maybe we'll see a YS-D3J in a year or two with fixed DS-TTL for LED trigger boards?

Sigh, it's not just LEDs.  Long story short, slave TTL mode doesn't work reliably, even triggered from a YS-D2J.

I connected my YS-D2J to my trigger board, and then hooked my YS-D3 to the slave port of my YS-D2J using a Sea&Sea sync cable.  Then held down the focus light button to switch my YS-D3 to slave TTL mode (cyan; backwards from YS-D2J colors...)

Now I should be able to use DS-TTL on the YS-D2J, and the YS-D3 should follow along by matching the strobe pulse lengths.  The actual strobe output lengths are pretty similar between the two (1/4 power is 302 us on YS-D2J and 341 on YS-D3; 1/32 power is 78 us on YS-D2J and 72 us on YS-D3; 1/128 power is 42 us on YS-D2J and 37 us on YS-D3).

But... epic failure.  Sometimes the YS-D3 doesn't fire at all, sometimes it fires at full power.  It doesn't seem to be able to match the right pulse lengths, even though it's now being triggered by a real xenon tube.

Ok, let's try the YS-D2 in manual mode, and see if the YS-D3 can follow along.  At least then I'd only have to turn *one* knob to adjust power on both strobes. 

Also very weirdly, when I change the strobe power on the YS-D2J, the YS-D3 seems to get the first shot wrong, but subsequent shots are better.  That seems like maybe a firmware bug?  But it kinda works, at least at GN22 - GN8.

At GN5.6, it doesn't trigger reliably.  And at GN4 on the YS-D2J, the YS-D3 stops triggering at all.  There's no longer enough light coming in the sync cable from a xenon tube flash.  That's probably why the first experiment failed; the preflash on the YS-D2J (roughly GN5.6) isn't bright enough to trigger the YS-D3 reliably.

But if I put both strobes on manual, the YS-D3 will trigger all the way down to GN1 on the YS-D2J (1/1024 power).  And it'll trigger at GN2 on the YS-D2J even if I use an old and much-abused crappy and dim single-fiber sync cable. 

So the YS-D3 can see adequate light coming in on the sync port.  But all its TTL implementations are broken.

Really hoping this is a defect in the first batches of strobes.

So, hey, if it IS a problem with early strobes, maybe we all have low-serial-number strobes.  But if someone's having trouble with higher-serial-number strobes too, then it's a design defect rather than a manufacturing one.

My already-dead YS-D3 is 180700757.

My still working-ish YS-D3 is 180700791.

If you've got a YS-D3 that isn't working with LED trigger TTL and your serial number is higher, what is it?  (Silver sticker in the battery compartment).

2 hours ago, Randall Spangler said:

I can't imagine they'd design a high-end strobe that can't be used in TTL with high-end cameras with LED trigger boards.  But then why wasn't this discovered in QA testing before the strobes were shipped?

Seriously!!!

Bluewater and I are still waiting for a response from Aquatica. We think the issue is with the Aquatica flash trigger. and yes, I cleaned the bloody things 

2 hours ago, sharkadobo said:

Seriously!!!

Bluewater and I are still waiting for a response from Aquatica. We think the issue is with the Aquatica flash trigger. and yes, I cleaned the bloody things 

I can generate arbitrary 1 us - 1 sec pulse lengths from my trigger board when I have it hooked to USB, accurate to 0.2 us, and I'm using a photodiode and 100 MHz scope to measure the strobe output.

I'm also using about the brightest red LEDs money can buy.  Red is the best wavelength for the combination of optical fiber and photodiode sensitivity (silicon photodiodes are twice as sensitive at 620 nm red than at green or blue).  They're so bright you can't even look at them directly.  I can't use a strobe in the housing, because there isn't enough space for me to put one that would cycle fast enough to use YS-D3 burst mode.  About the only way to get more power to the other end of the fiber optic cable would be to switch to laser diodes.  And then I'm worried I'd burn out the photodiodes (or my eyeballs).

I'm using Sea&Sea's own multi-fiber cables, in good shape.

And I'm still not getting consistent results from the YS-D3.  With slave TTL, either (unless I move the fiber optic cable from the slave port on my YS-D2J to directly in front of the tube, where it makes a shadow on the subject).  So I don't think it's the trigger board.  I think it's the strobes.  Either a design oversight or a manufacturing defect.

I'm happy to share more detailed results and scope traces, or to look at anyone else's strobes (of any model) for comparison.  It only takes about half a day to profile a strobe.

- Randall

Interesting information - so TTL has to send a pulse to get it read pushed through a lookup table which tells the flash how long to fire for.  I guess I can see why they do that as it allows you to shift the table up and down and apply compensation to the TTL output which you couldn't do if it  directly mimicked the TTL pulse length.

S&S seem to have been progressively reducing the sensitivity of their slave sensors over time based on what I've picked up helping people having triggering difficulties.   My instinct is to suggest people use a different strobe that is not known to have these triggering issues unless they want to trigger electrically.

@sharkadoboRegarding the trigger issue that fires off only one port and not the other the solution should be to see if your retailer will help with testing the trigger with various other strobes on that port.  You could :

• Test the RH port with other strobes
• Test the RH LED holding the cable directly touching the LED of the trigger with camera out of housing - to test alignment
• measure the Light output from each port - I'm am guessing that  a handheld flash meter might be able to measure this - again this would demonstrate whether or not the same light output is coming from each port.

This should help build a case with the reasons why the RH port trigger does not work.  If the output from the RH LED is lower or it won't trigger other strobes this would build a case for RMA -ing the trigger.  Or it might just prove that triggering of the YS-D2 strobes is marginal with this trigger.  Either way it should help point you towards a solution.