I was diving for fossils and had my go pro on my head using the head-strap, at the end of the dive my husband and I were getting ready to ascend. I was brushing a hair away from my face that was floating and then realized, the go pro was no longer on my head! We had just reached 700 PSI (well, he did, I was still at almost 1500...) anyway, I was thinking, i have to look just for a second, it couldn't have been lost that long ago. but while we were getting ready to ascend we kicked up a lot of silt, the vis was almost zero... I was still sitting on my knees at the bottom (30ft) i had to get up over the silt cloud and start going back the way I came, only about 5ft away from me I spotted the GoPro. I couldn't believe it. i thought I had lost it for sure. Needless to say, I always have it tethered to me now so that if it falls off it is still attached to me. Lesson learned!