I'm headed to Peurto Vallarta very soon. I'll be swimming in some clear blue water, so I picked up the red filter to see how well these things work. The science behind the filter is, is that it compensates for the lack of red as you go deeper underwater. Red is the first color to be lost making the white balance in the camera go nuts. Having the filter should give you a more natural and more corrected look. I got this bad boy for pretty cheap off Amazon for 30 bucks. Link here.
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