I'm with Michael and Dennis. 1 meter = 1.083 yards (give or take 1/2 inch). 26 meters X 1.083 = 28.16 yards X 3 = almost 85 feet. It has only happened once, but I experienced tunnel vision at 85 feet, diving on 36% EAN. I don't believe it was O tox because it was my first and only dive of the day and my PPO2 for that dive was about 1.2. The gas was checked once I mentioned my experience to the DM and the Dive shop, and it was found not to be contaminated. I did not consume any alcohol the night before, but I only got about 5 hrs of sleep. Perhaps that had something to do with it. I have done other dives to depths greater than 100' and have not experienced the same phenomenom. Bottom line, narcosis is always there. It's just a matter of how much of it there is, how much it affects you, and how you handle it. My tunnel vision went away the minute I ascended to about 78 feet.
Semper Safe,
Rick
Semper Safe,
Rick