Pavel Kolpakov

Sony A7-A9 cameras make workable 1/250 sync speed for flash synchronization, only if camera recognizes Sony compatible communication protocol at HotShoe (original flash, or TTL-Converter on the HotShoe). Manual trigger does not perform any communication via HotShoe. This case 1/160 is the maximum fast sync speed allowed by the camera. If set faster than 1/160, you will have a dark strip on the image (shutter curtain).

Yes, of course, it works. Retra team still did not give their new strobe for TTL-profile test yet. So, TTL-Converter firmware does not have any separate ttl-profile for Retra yet, but it has 2-3 similar ttl-profiles (DS-161, Pro-160, etc.), photographer can use one of them, no problem.

Some photographers shoot in manual mode, the others prefer TTL only, others switch TTL / M dependently of circumstances. It depends on personal preferences and habits. But in any case, TTL automation simplifies and speeds up the work, increases the percentage of suitable images. If we are talking about Sony A7-A9 cameras, there is one more important thing: maximum sync speed for usage with underwater strobes, - using simple manual trigger it is 1/160, but TTL communication protocol makes available up to 1/250. For many Sony users the 1/250 available shutter speed is a key feature.

Thank you. So, now Sea&Sea have 613-core cables: #50128, #50133 and #50135.

Please give me a link to look

Sea&Sea fiber optical cables are multicore, but I don't know what core is inside and what is the transmission index. We can only see that outer diameter is different from 613-core Nauticam, so probably this is another cable.

#16029 TTL board supports Optical TTL and Electric TTL simultaneously. The simple way is to use Optical TTL with this housing. But, If you want to install an electric bulkhead on the top, no problem, the bulkhead is available (Nikonos, Ikelite, S-6), that TTL board supports it.

Hi Patric, Yes, Nimar new housing (for Canon EOS RP) has only 1 optical bulkhead, moved to side. TTL Converter for it is product #16029 UWTechnics. The circuit board has the same shape as previous #16024, but includes 1 external LED moved to side. The correct picture will be available soon.

Technically they are very different, and have different specifications. For details of each product better contact to manufacturers.

You don't need Nauticam flash trigger this case. Just install TTL Converter #11075 into the housing.

If you purchase Nauticam for Sony A7-A9, you also can install internal TTL Converter specially developed for this line of housings. UWTechnics #11075 product:

Actually, some Nikon cameras allow "Rear curtain sync" option, only if recognize TTL protocol (flash, or TTL-Converter). But i am not sure regarding D500.

Hi Elmer, Here is a picture of installed TTL board for Nexus Nikon (product #11063 UWTechnics):

The best transmission index have 613-core fiber optical cables: Nauticam #26216, #26217, or HowShot 613L.