Seems to me that the wide angle lens you are using does not allow for zooming in. There are different kinds. I had a lens like that once - it would only allow me to zoom in to 30% - after that all got blurry. You'll have to consider before the dive, whether you want to leave it on for only landscape and wide angle shots - or take it off so you can do some closer stuff.
Situations / reasons not to zoom in:
- the more you zoom in, the shakier your shot - unless you have the camera pressed on the ground or other steady surface or tripod. You can test that on land and you'll immediately see.
- The further away your subject is -> the more you'd like to zoom in -> the more particles /plankton will be between your camera's lens and the subject. The more particles in the picture, the less "clean" your shot. Remedy: get as close as you possibly can, leave the zoom as wide as you can. Approach the animal slowly, s l o w l y... (Doing this will also teach you a lot of interesting stuff about the different critters down there - observe. You will find yourself approaching wildlife better and better as your stalking skills progress. Filming wildlife, it is not good enough to know how to handle a camera, you need to know the wildlife too.) Take a shot to be sure you have it "in the box". Wait a moment, look away, then continue inching forward. Watch carefully for any signs of fear: if the animal twitches - stop, look away, wait. Inch the housing forward. Take the next shot - do everything in slomo - no hasty movements - slow exhalations. Continue that until the animal "disappears" or you get the shot. Don't go away now though: Once you're in such a good position, the animal is relaxed and begins to return to it's natural behavior, you will see it doing things: feeding, cleaning etc. This is when it all gets r e a l l y interesting. This form of stalking / hunting - w i t h o u t harming wildlife - is what makes filming underwater so extremely rewarding to me. In the end patience pays off.
Situations in which zooming can help or is advantageous:
- setting focus. If you're not on auto-focus you might want to zoom in closely to a subject that's at a distance. Then set your focus manually. In most situations you'd choose to focus on the eye. Now zoom back out as far as you deem good. This method assures that - as long as neither you nor the subject have moved - your shot will be in perfect focus, even if disturbing plankton drifts by or a curious fish stops in front of your lens.
- big subject far away. Some creatures just won't let you get close. Example: a shark in the distance - and you don't want it to be a speck in your picture - you want it as large as possible. Here you have to find a compromise between a "clean", stable shot and a particle-filled, shaky one: focus manually or set the camera's focus to infinity to avoid the auto-focus pumping as it tries to find it's mark. Do not zoom in any more than your camera's stabilizer, your buoyancy and your fine touch on the housing permits. Hold the camera very lightly and gently. If you see that the shaking is too much you don't have a choice - zoom back until the shaking becomes acceptable - that's your call or trash the shot.
- macro: if you very close to a subject and would like to capture some detail by zooming in, you will find that the camera cannot focus, because you're t o o close. This is where macro lenses come in handy. Once you have a macro lens, you can get really close and zoom in all the way and you can capture amazing details. However, here the same applies: the more you zoom the greater the shake. In macro the shake gets really bad! So you really must find a stable spot onto which to place the housing, zoom in on the subject, manually focus - as described above - zoom back out as far as you want (or stay zoomed in that close!), p r e s s the housing down so it will not budge anymore, record.
Wow. Got a little taken away there... Lots of luck, have fun, enjoy! My biggest piece of advice: don't hurry, take your time for everything little thing you do - you just can't work as fast underwater as on land.
