RonFrank
Contributor
fcg_vi:
Hi Clark,
I just purchased the S70, so my *advice* is more based on photography experience, and my limited time with the camera rather than UW experience.
So far I'm impressed with the little 7mpix wonder. I am surprised that you were not able to use it without the flash. Did you try bumping up the ISO? Maybe you were just not getting enough available light, but I'd think that ISO 400 (while not ideal) would provide some options if you could not shoot at ISO 50.
For UW use I am planning on shooting as follows:
RAW in Tv mode, or manual mode, lowest ISO possible. Shutter at 1/60 or faster should be enough to freeze action, and Aperture as small as possible for DOF. One photographer indicated that he uses the shutter to control the background and the flash to handle the foreground/subject. This makes a lot of sense assuming you have enough flash power. I'm planning WB on UW, or Auto. When shooting RAW WB is not as big of a factor vs. jpg as one can change it in software. If shooting jpg, it's likely worth the effort to shoot using a custom WB.
If the images are not getting exposed properly, than I will go into manual mode, or adjust the exposure compensation. I can only guess on what metering mode will work best. I would start with Evaluative metering and see if that setting works well.
For focus, I'd setup the AF frame in manual mode to start. I don't like to allow the camera to set the focus point on it's own in general, and in Tv/A/M modes AiAF is not available.
One fun thing about the camera is that you can setup the Portrait mode one way, and then setup the M modes using different settings. You can then switch back and forth, and get a feel for what works best. One thing that is a bit tricky in this regard is that it's kinda hard to tell what setting one is selecting when using the dial with the camera in the housing. The mode can be displayed on the LCD for confirmation however.
I'd recommend using the histogram to judge exposure. The LCD does an OK job, but the histogram is a better indicator even if I *think* that what one is viewing is the green channel rather than the entire set of channels which can sometimes be misleading. So hold the exposure back a bit if it appears that it is boarderline. Slight underexposure when shooting digital is MUCH more recoverable vs. overexposure.
For a flash, I'm leaning towards the Sunpak G-Flash. While this flash does not seem to be very popular, about the only thing I have found lacking is a recycle time of 7 seconds which is none too speedy. However to increase the recycle time by much, one has to jump into a flash that runs 2x the cost. If not shooting a full power recycle times should be much better than the full power 7 second recycle time, but I can not really comment about the power until I try the flash for myself.
I have not purchased a flash yet, so I'm still a bit on the fence. But for my initial setup, I'm not sure I need to spend the $500+ on a Inon, Sea/Sea, or Ikelite flash. Flash is flash, and I'm not sure what the Sunpak lacks that I would need other than a faster recycle time. However the camera is not a speed deamon, and I've never been the type of photographer who felt the necessity to blast away at high speed to capture the *moment* unless one is shooing sports action, or birds in flight which is a horse of a different color :camera:
Another thought is that if you shoot in M mode, the flash does not use a preflash as the flash exposure is manually controlled. This means that you can attach just about any flash to the camera (that has a built in slave), and they should sync up. Of course one issue is back scatter, so you would want to likey set the internal flash at a low setting, and use the diffuser as well.
Maybe someone who has more UW experience with the camera can advise as to if my suggestions are good/bad/ugly :11: I will likely jump in the pool with this thing once I get some flood insurance setup, and then I'll take it to the hole or perch lake when I go next.
