arspcengr:
I have ... Olympus 5050 and I am considering purchasing a strobe. I have yet to get the housing, but it will be pt-015 or the newer Ikelite if it will faciliate what I would like to do.
I would like to purchase a strobe that compliments the 5050 the best and can also be used for a film camera in an underwater housing. I am going to start taking underwater photos with the 5050, but in the future I would like to also use a housed film camera. I would like to buy just one strobe that I could move from one platform to the other.
You can do close-up photography very well with the on-camera flash, but for subjects farther than a foot, backscatter from suspended particles in the water will ruin your shots -- you need an external flash a distance from your lens to avoid backscatter. Sounds simple enough, but most older flashes just don't work with digital cameras.
Why? Because most digital cameras use flash a little differently than film cameras do. The Olympus digitals and many others emit a brief pre-flash for exposure testing, prior to the main flash. Old strobes designed for film cameras can't work properly with this double flash, but new ones designed for digital cameras can. So be sure to buy a flash that is designed for digital cameras (it will also work with any film camera it can connect to).
These include the Ikelite DS-50 and DS-125 with TTL controller, the Sea and Sea YS-25DX and YS-90DX with fiber optic cable, the INON 180 and 220 strobes with fiber optic cable, and the (very expensive) Light and Motion Tetra housing with Nikonos style TTL flash.
The optically coupled flashes have sensors that observe the on-camera flash, and try to mimic it. (They use this optical link because until recently there was no physical connector on the camera housing to bring out the flash hot shoe, except for the L$M.) Sometimes this optically coupled setup does not work well, because of optical feedback from the external flash into the sensor, causing an extended exposure. People generally use these manually. In fact, the optically coupled Sea and Sea flashes must be used manually, with the flash in manual exposure mode based on the distance to subject and the aperture.
Many of the photographers on this board use this manual exposure method with good results. However, I am used to my land camera working in full TTL exposure mode -- this is a big deal to me because all my land shots have to be good, and auto TTL flash exposure is crucial for achieving that.
Luckily there are two new products from Ikelite and Olympus which connect electrically to the hot shoe with copper cables for future generation cameras. These new systems can do true TTL flash exposure with the 5060, emitting the pre-flash and main flash under precise control from your camera. This puts your camera's auto exposure system in control, and is more likely to give you good exposures most of the time. The new Ikelite 5060 housing supports the Ikelite DS-50 and DS-125 with hard wired Ikelite TTL connections, while the Olympus 5060 housing connects to the very limited Olympus FL-20 flash in the PFL-01 housing.
For the Oly 5050, Ikelite is planning to release a new 5050 housing with true TTL flash control next month, and it will allow connecting to Ikelite's DS-50 or DS-125 with simple copper cables to give true TTL flash control. For that reason I would suggest waiting and getting this new Ikelite housing and either of the Ikelite digital flashes. For details go to:
http://www.ikelite.com/web_pages/oly_5050.html
If you are a tinkerer, you might consider another approach. A gentleman in Germany developed a device to connect the 5050 in a PT-015 housing to external strobes and give full TTL auto flash control. Because I already have the PT-015 housing and YS-90DX strobe, this is more cost effective for me than buying a new housing, new strobe, cables, arms and so on.
I bought one and am still evaluating it. It seems to work on land (with dual strobes no less!), but I have not dived with it. I will post a review with pictures when I have some results to show. Here is a pointer to that device:
http://www.muenster.de/~matthias/blitz/oly2nikone.htm
Whew! Bet that is more than you needed to know. I suspect that most people will be happy with the new Ikelite 5050 housing and an Ikelite digital strobe, and you can certainly use the Ikelite strobe on other Ikelite film camera housings. Do check that the film camera you want has an available housing before you buy it. Ikelite has by far the broadest line of housings for film cameras, so that makes it a pretty safe bet. Good luck!
