Demonstrating that filters do deal effectively with white balance
A filter works but seems inconvenient and unnecessary with the right camera.
The photos left and right are from Magic Filter's web site. Both from a compact on auto exposure
and auto white balance. I have no idea whether from snorkeling or scuba diving or the depth.
If you are going to use a filter, choose a solid lens filter
If your camera housing is really simple it won't even have a thread for external, wet-lens mounting -
(it must, simple as that).
For this situation, Magic filters can come as sheets of plastic which are cut and attach to the camera
lens surround, or inside the underwater housing. I've read of their being stuck on with Blu Tack.
Clearly, the only way to remove the filter is to go ashore. Hmmmm!
So, make sure your underwater housing has an external thread. Then you buy a solid lens filter which
screws to the outside of the housing.
At least it can be screwed on and off in the water.
for external lens screw mounting
Why filters aren't suitable for snorkeling photography of fish but are fine for static objects such as coral
Why I don't recomment filters. Choose a camera that automatically sorts white balance. It makes
life so much simpler.
If photographing just two or three metres down, or less, on a very bright day, filters
can overdo their job and photos can have a red tinge.
So at these shallow depths the filter needs to be removed. This is why solid lens filters are clearly
better than cut sheets. They can be screwed on and off without going ashore.
But, screwing a filter on or off, messes seriously with your dive, probably losing the shot.
Often as you go to photograph something it moves up, or more usually, down. If you have a shot when
the filter should be on, but it's off (or vice versa), you
have simply lost your shot. Filters are great for static things ie corals etc.
They don't seem practical for those of us snorkeling and photographing fish at
unpredictable depths, often, within that upper 3 metre zone.