Which dome port?

[tamas970]

Yes, it comes with the FL-LM1 flash. It's power is variable, I'll test the TTL functionality a bit thoroughly with my Inons later today.

I checked the sync speed of my e-pl5 with 2 land-use flashes (Metz 50AF-1 and an ancient Sunpak 355AF), in case the Metz I covered the communication port (cannot be done with the with the proprietary Olympus port the FL-LM1 uses). The Sunpak doesn't communicate anyway. Seems, 1/400 is acceptable with <<10% coverage loss (the firmware allows only 1/250 for the FL-LM1 and the miserable 1/160 for any hotshoe mounted 3rd party flashes):

 

[ksporry]

I don't think I understand this. Presumably when you do the sync test with the sunpak and metz, you use those as optical slaves triggered by the FL-LM1? How is it possible to get 1/350 or 1/400 when the firmware only allows 1/250? And how do you get them triggered when you cover the comms port?

Also, how much does such a test matter when you have to use the FL-LM1 in the housing to optically trigger any external flashes? I'd imagine that when using a UFL-1 or 2, the setup is simply optimised and limited to 1/250 unless you go full manual on the external flashes.

 

[tamas970]

The flashes were simply mounted on the hotshoe, after removing the FL-LM1.

The communication happens on the smaller pins of the hotshoe. The "fire" command is a voltage signal between the big central pin and the shoe itself - this primitive command is always released, even if I deliberately turn off the flash in the menu. The body "senses" the presence of the flash (and applies the 1/250 maximum on the shutter speed) only if something communicates on the communication pins, which I covered.

Also, how much does such a test matter when you have to use the FL-LM1 in the housing to optically trigger any external flashes?

There is an alternative to the FL-LM1, I linked it multiple times above:
Little micro strobe batch! - Lights, Strobes, and Lighting Technique - Wetpixel :: Underwater Photography Forums

Additional advangage, that the microflash won't use your camera's batteries and the cycle time is fast (<0.5sec). Drawback is it seems nobody mass-produce them, you have to solder the parts together.

I just quick-tested one of my Inons - using the sunpak as master, it synced nicely at 1/320. I hope I can get the same with a microflash.

 

[PHIL RUDIN]

This is not a new concept and goes back to film days. Using a non-propriety strobe (this includes strobes like the Inon and S&S using wired not fiber connections) will allow higher strobes syncs in non-TTL shooting. Most top out at around 1/320th before you begin to see the black line across the frame. Using proprietary strobes like the pop-up strobes or the Olympus strobes that mount to the hot shoe will only allow the highest sync speed but they work in TTL and with fiber optics will allow strobes like the Inon's to work in S-TTL.

So with the Nauticam housing for the Olympus EM5 you can add a $130.00 Nikonos V bulkhead and shoot your Inon or S&S strobes using wire cables but not in TTL.

The problem with the "little micro strobe" is that it will not TTL and if you drop a little water onto it from your hair or whatever when you open the housing it is likely to be toast. These little strobes were developed for use with the high end cameras like the Canon and Nikon because they have no pop-up or mini strobe and as a result can not be used in a housing with fiber optic cables.

Working out a way to have these strobes work in TTL is a challenge and when they do come to market they will likely first be for Canon and Nikon TTL.

 

[tamas970]

Yeah, first thread I saw in the topic was somewhere from 2005 and haven't seen a TTL one ever since.That would need a much more sophisticated IC (right now it's basically a MOSFET, 2 batteries and a LED).TTL is an issue, you have to decide before the dive if you go for TTL and put in the accessory flash or youwant the high sync and put in this gadget. Actually killing it is not much of an issue, total budget of a DIY projectis probably 30$ + 20 min work (I would immediately order parts & make 2-3 pcs).

 

[ksporry]

So here's a controversial idea. There are VERY small radio triggers on the market. I don't know how well radio waves work underwater and inside housings, but when the distance is less than 2 feet, it could almost be possible to use cheap Chinese total radio triggers and install them inside the flash housings somehow. Requires some DIY on the flash side, but could be worth the effort.

 

[tamas970]

As for radio: radio waves don't propagate nicely underwater, not to mention metal housings. Still, there are some applications built on separately housed Pocketwizards. I don't know it it is worth the investment, I'd rather stay on the beaten track and go optical. Inon has a wireless system using mirrors on its new strobes (new gen. Z240, D2000, S2000) - it still relies on the accessory flash. However, I don't see it to be a better solution than the fiber system, because you have to readjust the mirrors anytime you move your strobe arms.

Regarding strobe housings (which you'd go for if you want a radio trigger): dedicated strobes are altogether not more expensive, lighter and smaller - cannot be fired with radio though.

There is a guy on ebay offering custom (and btw cool) design strobe housings. I see one application, where it might be worth to consider: if you want to bring a supernova - like the Metz 58 AF underwater with GN29 at the wide end of the zoom (and anyway, the zoom functionality).

Anyway, we should probably continue the discussion in the Strobes topic

 

[ksporry]

slight change of direction: The Olympus Dome PPO-E04, does that fit the panasonic 7-14mm lens?

 

[PHIL RUDIN]

Ksporry,

The Olympus PPO-E04 port was designed for use with the Olympus 7-14mm lens for the Olympus DSLR cameras and housings, NOT the mirrorless camera housings. You can mount this port to the Olympus housing for the OMD EM5 with a port adapter and if should work but you will need a port extension. I think it would make more sense to use the ZEN port for the Olympus housings and the7-14mm Zen or Nauticam ports for the Nauticam housings.

Phil Rudin

 

[ksporry]

Actually, the PPO-E04 is supposed to be compatible with the PT-EP10 housing and the olympus 9-18 lens (and several others). What threw me off was the 7-14 spec, and initially I just assumed it was the panasonic one, but recently I learned its the olympus 7-14, which is for the 4/3 system, not the m4/3 system (pen). However, I do think the ZEN for the PT-EP10 or the nauticam for the nauticam body is more suitable for the panasonic 7-14.

As for flash cables, are these an industry standard (i.e. can I use Olympus optical flash cables on a nauticam housing, or can I use another brand cable on the olympus housing? I'd like to get a set of Z240's but I would like to know if the cables are universal or not.
Thanks.