Again, there is no "starting" point manual expousre to set--there is no such thing.
Auto works fine on both my Oly 770 and my two 570IS and my Nikon slrs.
I have been using the Av mode or the Tv mode (570IS) which allows me to set a specific f stop or shutter speed and the camera automatically sets the correct corresponding setting. Full auto chooses both BUT--important---the camera is going to set an equivilent exposure regardless UNLESS you bias it using either the plus or minus under the fucntion button on the 570. Program is essentially auto--read the manual.
I am using the Tv mode last time out and using a Sekonic Marine Meter to set my shutter speed. If I decide instead to use my strobe, D2000, then I have been using either full auto or Av with the strobe in either sTTL or auto and the camera's strobe set to 1/3. However, I have used full auto without the strobe and both with the camera strobe in OFF or automatic.
I can tell you don't understand the operation of your camera, I am not being mean but you need to study those books it seems becuase they give good advice to operating your camera.
There are I think three uw modes including a "portrait mode" I think it is called. There are three expousre meter settings including, center, evaluative and spot. The camera strobe has ON, auto, Forced and manual (in some modes the camera also has 1/3, 2/3, 3/3 instead of auto).
Yes, there is a auto mode for the strobe which when the camera is set in auto the strobe defaults to auto and I think you can also choose OFF.
It is kind of hard to write all this down and have it come out understandable, that is why I refer you to the camera manuals and then if you have a specific question ask it.
Since your a new diver and your concerned with "task" loading whatever that might be then set the camera to auto and let it fuss with the exposure. After a few shots you should be able to decide what additional adjustments should be made. You can see the picture you just took for about two seconds on the viewer. You can also set that time, that the picture stays on the screen, longer or shorter, it is in the manual.
Even though I have an external strobe, strobes are only good for relatively close shots, if I am taking a wide scene using my wet mount Inon 165 I set the strobe to off, camera in auto or I will go to Tv or manual only if I have something I want to accomplish differently from what I have learned my camera would do on it's own exposure choice.
Again, most P&S cameras only have an auto mode or maybe a program mode with a exposure compensation of plus or minus two f stops. They do not have a manual setting. The 570IS is unusual in that regard. The manual setting comes into play when using the external strobe. Since your not using an external strobe you should probably be in auto mode for generic snap shots.
Looking at other people's pictures taken in different places and water conditions will tell you nothing really IMO.
Hope that helps. I guarantee the camera can do better on it's own than you can just guessing at an exposure setting randomly. BTW, if you use the camera's light meter it is going to tell you to set exactly the same settings it would choose in auto--YOU have to bias them or change them to suit your desired results. If you use an external light meter like my Sekonic then still it is only averaging the scene, if there is back lighting or shadows etc I then look at the meter and then using my experiance with my camera adjust the camera in manual (or whatever mode) to accomplish MY desired result. That is why you use manual instead of auto--to do something different from what the camera would do, otherwise set it in auto.
It would not matter if you were on the moon, in your backyard or 100 feet underwater, the camera's light meter and exposure program can and will set what it think's to be the optimum setting and most of the time unless you have something you especially want different, like using a fast shutter speed to freeze action or a wide lens oening to blurr the back ground (not really possible with our P&S) or compensate for wide brightness range in the scene or backlighting etc then the camera will do a better job than yourself.
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