Hi jensen and Blade.
We discussed here earlier about effects of yellow tinted lensen while diving. I at least came to conclusion that yellow is'nt very likely to help one see while underwater.
The yellow tinted glass decreases the amount of yellow light comong through. The water itself does the same thing very efficicantly when at depth. This depth does not mean much more than say 10 meters. If one goes to 10 meters and takes a picture of yellow or red fish without flash, the fish in the picture is likely to look less colorfull. The human eye converts some color, but the film / ccd does not do that, therefore the picture will get colors more towards the blue spectrum.
If using red or yellow tinted mask at the same depth you get the filthering done twice, first the water and then your mask. The problem with this is that the overall amount of light coming to your eyes is decreased.
This is all theory though, have not tried that out. If i have time i dig some information about color shifting underwater and filthering. Human eye is ofcourse a factor since the eye/brain does a lot with the perceived image anyhow and i dont know how that affects.
Good luck with your masks. Let us know how it works.
br.
Tuomo