Here is a video I shot a little while back, using up to 6 GoPro Hero2 HD camera's. The point was to try and compare filters but conditions ended up quite poor and results were not very conclusive. Filters used URPro CY dome for GoPro dive and Blurfix URPro CY 55mm thread on Blurfix Backscatter Magic Flip for GoPro Dive Oculus filter for GoPro Dive The main thing found is that the Hero2 has pretty bad auto white balance and doing a filter comparison in less then ideal conditions just didn't work and results dont show as much as I hoped. I didn't post this originally as I thought it would just cause more confusion as the WB was more of an issue then the filters at most times. The results under 15-20m where generally ok but still some wb issues, beyond that in this light and vis all cameras struggled in these conditions. I did try some more filter tests using protune modes in the hd2 with newer firmware recently, but WB is still fully auto there and so results were not any more consistent. I intended to test the max depth of each filters effectiveness but the conditions reduced the effective range compared to other dives I have done in better conditions. As I dont actually own so many cameras trying to arrange them and a dive trip together had to be planned in advance with no idea of what the weather will end up bringing to us. I got the worst case scenario as these were the worst vis conditions of all my dives at this site and it was quite disappointing. The data overlay is accurate for depth but for some reason the air pressure reading is not correct. My computer does give correct air reading on its screen but the recorded data is about as random as the GoPro's AWB, I apparently would have died on some of these dives if you pay close attention to the air pressure left lol. I will be back here in about a month and will shoot some video with my hero3 black and it will be interesting to see how it does. With results I have had using cam raw WB the wb issues have never come around and no greened out footage at these same depths using this option in the new camera. It should also give a more effective Idea of how well the filter works at depths without the wb issues. With some luck we will also get some better conditions that are quite likely here. ... https://www.youtube.com/watch?v=NeLn-B-3faw