i guess i should address this to at least jake:

ikelite has a gadget for under $150 that apparently can be used to achieve manual control of the substrobe (DS-125 or DS-50) where there was initially only TTL control. anyone think this would result in any significant improved control of the substrobe flash?

saw the device at bhphoto.com

read about it at ikelite.com but we know how they are ;)

Bob, unless you are in a rush, I would wait. A combined controller is on the horizon.

The manual controller gives you control similar to the Sea & Sea YS-90DX, in that you have variable output of the strobe in 12 steps (it could be 10 instead of twelve, I don't recall). One nifty feature that makes the manual controller attractive is that it will works both optically and electrically. It can trigger off the camera's internal strobe, or it can be connected to a hardwired strobe connection (if your housing is equipped with one). Hopefully, the combined controller will offer the same features and optically controlled TTL like the original.

Ike has been sort of secretive about when the combined controller will be out, but I expect it in a matter of 2 or 3 months.

jeff,

thanks for that input. i really don't even yet have a handle on what my substrobe issues might be, i know jake believes the sony F707 and the DS-125 strobe lacks some control...

i'll just keep an eye on this one...

thanks again,

Wasn't aware of it Bob, but it sounds very interesting. Jeff - I'll definitely wait. I don't like being a guinea pig with things like this :-)

Jake

Bob,

"anyone think this would result in any significant improved control of the substrobe flash?"

imho Yes.

I have an Ikelite manual controller and a ttl sensor. The ten step man con is hooked up to my ds 125 and the ttl is advising my ds 50. I use this system in tandem.

I found the manual controller easier to manipulate, overall, especially for close focus wide angle ( cfwa )shots. Last year I found the ttl sensor with the ds 50 to perform well on macro images and most all night shots.

Keep in mind that if you choose the ttl sensor with the ds 125, you still get both manual and ttl, although the manual control is limited to 1/2,1/4, and 1/8th power. I've seen excellent results by many photographers using this ttl/manual system.

I echo Jeff's advise if time is on your side. Why not have it all. But if I had to choose today, I'd still get the man con.

hth,
kadushi bob

kadushi bob,

hey thanks,

i guess i wasn't sure but i thought manual control of my DS-125 was not possible using the TTL cord. if i can experiment with 1/2, 1/4, and 1/8 power settings maybe i can get a better feel...

so far i have been completely relying on automatic features...funny thing about the ikelite website, where they ask the question, "if you are letting the camera control flash above water what makes you think you need to manually control the flash underwater" ???

(the manual controller must be a customer request ed feature???)

whatever,

thanks for the answers ;)

ok...so for anyone else - there may be a potential problem with TTL flash control in certain lighting situations - ones where there is another light source...so apparently manual control of the substrobe is desirable in these situations, apparently not so much a problem in macro or night shooting...

thanks bob!

My problem is not the one of blowing out my highlights with my flash, but quite the opposite - the TTL shuts offs the strobe (I think) before the scene has had enough light. So if there's a manual control that will let me add EVs to the TTL strobe settings, that would be great.

Jake

Jake,

I am not familiar at all with a Sony digicam and it's sub menus. Within my Oly sub menus, I can program it to add or subtract up to 2 EV's. If the characteristic your are describing is hopefully consistent, adjusting the EV accordingly (+1?) may be an option.

kadushi bob

Bob,

When you state " another light source" are you referring to ambient light?

Consider separating the photographic image into two categories, foreground and background. The foreground will be lit by your substrobe and the background (ambient) lighting is controlled by your f-stop and shutter speed. The faster the shutter speed, the darker the background.

Lets say that macro shots are all foreground, therefore all lighting comes from your substrobe. In this scenario TTL metering
shines.

Many reef scenes include open water. TTL struggles with this because the light being emitted from your substrobe isn't reflected back to the camera to aid in proper calculations. The camera's brain thinks insufficient lighting is reaching the background and commands the shutter to remain open. The tendency is for overblown foregrounds.

With this understanding it is still possible to achieve quality images with TTL and open water shots. One solution is to choose your metering option accordingly. It is possible to tell your camera to zero in on a specific area ( spot metering) of the total image and rely solely on this for it's calculations. I would recommend searching for the images of Don Hughes ( a.k.a. meister) for examples of this technique.

kadushi bob

bob,

yes, ambient light - that's what i got out of Jay's article - the ambient light can be a source of TTL confusion.

shooting in auto mode, i note most of my shots are taken at F2 or F2.2 - some definite possible over exposure there;) ...i think jake is shooting with smaller aperature so maybe he has the opposite problem.

i suppose using the manual controls/modes other than automatic is probably a better way to handle the issue, however given that such camera operation can get to be a bit clumsy underwater with the camera enclosed in a housing, it would be nice to be able to control the flash externally...

i think i still can do the spot metering vs pattern or whatever i have currently so i will try that also.

thanks,

Bob F.,

I shoot the camera in manual mode, and the EV setting is not accessible there on a Sony F707.

Jake

anyway, having much better luck at night...except i gotta remember to turn off the modeling light so i can see the night framing hologram and actually frame/focus my subject;)

this pic really has good color and detail, might not see in this reduced version but even some of "cactus bob's" coral cup flanges are observable in the upper lefthand portion...



same wide aperature, no other ambient light (except maybe from the modeling light)...