Ikelite DS-50 and TTL

Hi,

I've been communicating with Ikelite regarding their DS-50 substrobe and cameras that could use it in TTL mode.

Ikelite claim that the Fujifilm FinePix S2 Pro and Nikon Coolpix 5000 and 5700 are able to use this flash in true TTL mode.

If it's true that the Coolpix 5000 and 5700 can, then why not 5400? And why did Nikon invent DTTL (which is not TTL at all) for their D100, D1, D1X and D1H systems if they had TTL working for 5000 and 5700?

I don't get it. Please explain!

/Anders

Hi Anders,

Yes, this is confusing. For now, just drop the DS50 out of this discussion. It's a TTL strobe, just like a lot of other TTL strobes that will work w/ the cameras mentioned.

I'm not sure 100% but I'd bet that TTL will work with the 5400... It's hard to say. The reason is that the CP5000, 5700, and probablyl the 5400 don't do "real" TTL either. They use a light sensor on the front of the camera to meter flash light returning to the camera. They do NOT meter flash light returning to the CCD.

The reason that Nikon developed D-TTL is that light doesn't really reflect off of a CCD. The CCD absorbs light and converts it to electric current. So the definition of film ttl "the camera meters reflected light off of the film plane and shuts down the flash accordingly" just doesn't apply.

Somehow, the properties of Fuji's proprietary "SuperCCD" make it just reflective enough for "regular old film TTL" to work. So "true TTL" actually works with the S2pro.

I hope that is a good explanation. As you can see, none of this actually depends on the strobe. It's all about the camera.

Cheers

James

Placement of the camera sensor is why we decided TTL would not work in the 5400 housing.

Thank you. Now I understand!

A TTL strobe is simply a strobe that can be externally controlled. (Different camera brands have different TTL standards.)

The Nikon CoolPix 5000, 5400 & 5700 can control such strobes, but not TTL (Through-The-Lens, and during exposure).

DTTL is Through-The-Lens, but the exposure measurements are done before actually taking the picture. Normal TTL strobes are not compatible with DTTL.

Currently I have a Canon PowerShot S40 with a WP-DC300. I want to buy a strobe that works with this camera/house combination, and leaves me enough options for my next camera/house combination. Possible next cameras could be something like:

Canon PowerShot G5

Olympus C-5060 Wide Zoom

Nikon Coolpix 5400

Any suggestions or recommendatins on choosing a strobe?

/Anders

For a good foundation of understanding regarding current substrobes in the marketplace with digital capabilities, may I suggest reading this article authored by sharpdiver:

http://www.digitaldiver.info/images/strobe...rticlescrn2.pdf

Just one more point. According to Ike, his substobes, DS 50 and DS 125, should only be controlled by a manual sensor for use with Canon S series digicams. I believe this is due to the characteristics of the Canon preflash.

It is always refreshing to see members of this forum do research before asking questions, just like you have. I wish you good luck in your search.

Yes, the DS-50 and CP 5000 are true TTL with a synch cord. The camera synchs up to 1/250 with a DS-50. I asked Ikelite this question directly. You do not need to use manual flash settings with the CP 5000. At least I didn't, and it just worked great in the water.

From Ikelite website re the CP 5000 housing (#6190):

"The camera flash is blocked by the housing. A bulkhead is included to allow use of a sync cord with any TTL SubStrobe. Strobes made before 6/1/01 require modification. Mount for Nikonos strobes is available.

A deflector is also included to allow the new DS series Digital SubStrobes to be triggered by our wireless TTL Slave Sensors but sync cord is recommended for greatest versatility."