Getting my first uw camera - help me understand! (sync cord, optical cable and ttl)

[Issue]

Hello.

I plan to buy my first uw camera for photo before summer. I have been reading a lot about uw photography and i starting to get a hang about what i want. There is so much to learn!

At the moment it looks like i will end up with a6500, 10-18mm and a nauticam house with sea&sea ys-d2.

But there is one part where i cant find any clear info and i feel that i am getting different answers depending on who i ask. The topic is; Sync cord vs optic cabel.

I understand the difference in how they work. One sends light from flash and the other electrical signal. One is dependent on how fast the internal flash reload and the other how fast the strobes reload?

I see this video from bluewaterdivingstore where sync cord seem to be 10x faster than optic cabel.

Now i have been told that this is not true without a ttl converter? Or flashtrigger? Difference?

I also get answers that there IS a big difference in speed even without ttl converter.

I dont know if i need this speed, but i sure know i want it. But i am not sure how big difference it will do on my camera. Nauticam say there is no ttl converter for it atm.

I am aware of the increased risk for flooding the house witg sync cord.

Just to sum up, here are some questions i want to understand;
Is there a difference in shooting speed with sync cord vs. optical without ttl converter?

If no, why do i need a ttl converter? Is it that sync cord does not support ttl without ttl converter?

Is flashtrigger the same as ttl converter?

Why do i need sync cord for optical cables? I understand that optical already supports ttl. And speed should still be limited by internal flash?

Will the reload speed be as slow as in the youtube clip above with a6500 aswell?

I wrote this on my phone at work so im sorry if the spelling or english is bad.
Hope anyone can help me sort this out.

Thanks in advance!

 

[PatW]

The fiber optic cable has an advantage. It does not have to pierce the housing so there is one less place for you to get a leak. But it requires your on camera flash to go off and that requires more battery useage. Battery usage can be a limiting factor depending on your usage. It was when I used a point and shoot. The shutter lag was such that sometimes it was shoot and hope.

Cycle times on strobes vary. The time also depends on whether the strobes are set near full blast. I use ikelite strobes and they cycle extremely quickly. But their drawback is being huge and heavy.

TTL is when your camera adjusts the strobe for the light metered by the camera's sensors. I don't use it. I shoot manual. I do this because the camera's sensor can get the exposure wrong by a whole bunch.

If there is a vender who carries the equipment locally it is worth going. I live in Florida. When I got my system, I hopped in the car and drove three hours to talk to them at Reef Photo.

 

[Storker]

TTL is when your camera adjusts the strobe for the light metered by the camera's sensors. I don't use it. I shoot manual. I do this because the camera's sensor can get the exposure wrong by a whole bunch.

IME it depends a lot on the camera/strobe combo. I use fiber optic TTL all the time and am quite happy with the results (Olympus OM-D, Inon Z240). Occasionally, I have to pull or push the exposure a step or two in post, but since I'm shooting raw files, that's really not an issue. And I have to pull the blacks and fix the WB anyway, so it's not as if that's much of an issue.

 

[Issue]

The fiber optic cable..

I appreciate you taking time to answer the thread, however i already knew most of what you wrote.

 

[watboy]

For true TTL to work, the camera needs to directly communicate with the strobe through a wired (sometimes radio) connection. There is no standard protocol, so unless you are using the same brand strobes as camera, TTL will not work unless you get a converter, which specifically allows strobe of brand x to work with camera brand y. Its not just brand, you need to check specific strobe models with camera models. A flash trigger is just small led lights that goes on the camera hotshoe and flashes on, and cannot do TTL. It is used for fiber optic connections and strobes in manual mode. The main advantage is you don't need to have a bulkhead connector. You probably already know, but to wrap it it up, optically fired strobes just look for another strobe firing and fires at the same time for the same duration. STTL, means the strobe can mimic the camera's existing TTL strobe, usually its an built in/pop up strobe or small hotshoe strobe like the Olympus MFT.

Now, you absolutely positively do not need to have strobes cycle that fast. TTL works pretty good for macro, but basically not at all for wide angle and you will have to learn manual and 9/10 times manual wide angle means full power. Lastly, rapid strobe firings is just going to blind, stress or otherwise annoy critters. I've seen critters fall over dead from being strobed to death.

 

[Issue]

For true TTL to work, the camera needs to directly communicate with the strobe through a wired (sometimes radio) connection. There is no standard protocol, so unless you are using the same brand strobes as camera, TTL will not work unless you get a converter, which specifically allows strobe of brand x to work with camera brand y. Its not just brand, you need to check specific strobe models with camera models. A flash trigger is just small led lights that goes on the camera hotshoe and flashes on, and cannot do TTL. It is used for fiber optic connections and strobes in manual mode. The main advantage is you don't need to have a bulkhead connector. You probably already know, but to wrap it it up, optically fired strobes just look for another strobe firing and fires at the same time for the same duration. STTL, means the strobe can mimic the camera's existing TTL strobe, usually its an built in/pop up strobe or small hotshoe strobe like the Olympus MFT.

Now, you absolutely positively do not need to have strobes cycle that fast. TTL works pretty good for macro, but basically not at all for wide angle and you will have to learn manual and 9/10 times manual wide angle means full power. Lastly, rapid strobe firings is just going to blind, stress or otherwise annoy critters. I've seen critters fall over dead from being strobed to death.

Thanks for that answer!

I ordered yesterday and i will use nauticam a6500 house with optical cables to sea & sea ys-d2. I understand that TTL will work with this setup, but it wont shoot as fast as in my video in TS? Good thing i dont need that speed then.

 

[KeithG]

Thanks for that answer!

I ordered yesterday and i will use nauticam a6500 house with optical cables to sea & sea ys-d2. I understand that TTL will work with this setup, but it wont shoot as fast as in my video in TS? Good thing i dont need that speed then.

I claim you will find certain situations where you want the speed! Juvenile spotted drums are constantly in motion. Getting a good shot without burst mode is pure luck.

But do not be misled too much by the video. It depicts a best case, not worst case scenario. The YS D2 has a recycle time of around 1.5 seconds if a full dump is required. Obviously the video showed the YS D2 operating at a much lower power level. If you need full power, then the YS D2 will still only take a picture every 1.5 seconds, even when using a wired sync cable.

Did you order 1 strobe or 2? A second strobe will let you work at a (slightly) lower power setting and will shorten the strobe recycle time.

Shooting at a lower power setting may make the recycle time nearly instant for very shorts bursts. You may have noticed in the video that the strobe recycle time abruptly slowed down after about 2 seconds. Since the low power setting does not fully drain the strobe capacitor the strobe can refire instantly. For a while, until the capacitor gets drained down.

 

[Issue]

I claim you will find certain situations where you want the speed! Juvenile spotted drums are constantly in motion. Getting a good shot without burst mode is pure luck.

But do not be misled too much by the video. It depicts a best case, not worst case scenario. The YS D2 has a recycle time of around 1.5 seconds if a full dump is required. Obviously the video showed the YS D2 operating at a much lower power level. If you need full power, then the YS D2 will still only take a picture every 1.5 seconds, even when using a wired sync cable.

Did you order 1 strobe or 2? A second strobe will let you work at a (slightly) lower power setting and will shorten the strobe recycle time.

Shooting at a lower power setting may make the recycle time nearly instant for very shorts bursts. You may have noticed in the video that the strobe recycle time abruptly slowed down after about 2 seconds. Since the low power setting does not fully drain the strobe capacitor the strobe can refire instantly. For a while, until the capacitor gets drained down.

Ah, thanks for another great answer.

I ordered two strobes.