I’d be interested in comments on this approach. Especially if you can suggest improvements!
I’m using an Olympus C5050-Zoom with the PT-015 housing. The camera has a pretty good “TTL” system for determining the amount of flash for each shot, and I wanted to use this underwater. But …
I found, as expected, that the housing casts a shadow on one corner of macro photos when using the flash for wide-angle. And it’s worse for super-macro. Additionally, for super-macro the only way to use the flash is in slave mode, where there is no automatic flash intensity control anyway.
I bought a close-up lens so in the end I never used the super-macro mode. I attached a diffuser on the side of the close-up lens, so when I attach the close-up lens the diffuser gets attached as well.
For macro mode, without the close-up lens, I used a “less diffuse” diffuser at the front of the lens barrel of the housing, tied on with a piece of elastic, and I swivel it to the bottom of the housing when I don't need it.
Incidentally the diffusers are made by cutting pieces out of the lids of plastic kitchen containers. I’d be interested to know if anyone can make suggestions as to a better way to go for this. I just used the materials at hand in the short time available before setting off on my trip.
I ended up for most of my macro shots using manual or aperture priority mode, setting the aperture as small as possible to get better depth of field.
Of course this approach doesn't allow any flexibility in the direction of the lighting...
You can see some sample photos (low resolution only) at http://uk.photos.yahoo.com/d3m2m. None of these have been processed in Photoshop, but some have been cropped. All the close-up photos (excep the Mandarinfish, I think) in the Kapalai directory use this system for the flash. A few of them also had an HID light on the right, but I doubt that this contributed anything significant to the light in the image as I was using quite short exposure times.
-David
