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"The first rule of solo-diving is you do not talk about solo-diving."
Nothing real current. Last update I saw was in mid May. Motor skills improving, can walk slowly without a walker. Neuro & sensory functions still slower than before. He drove the boat in mid May, and was able to prepare the fish for the ever so important tacos.
Interesting. I never gave this subject much thought because I used a computer from the beginning. But I've always been a little hazy on the concept of "bottom time" as opposed to dive time. Sure, on a square-ish profile like a wreck dive from a boat it seems clear enough; even if you drop to the sand and work your way up to the top of the wreck, your bottom time ends when you start up the anchor line. But most of my dives aren't like that--most of the time, there's stuff to see and linger over at least most of the way to the safety stop depth. My favorite local night dive is at Veteran's Park in Redondo Beach. We usually surface swim out to about the end of the pier (which still puts us in only about 20-30 feet of water), then follow the slope down into the canyon. Sometimes we go to the monument (60-65 ft); sometimes to the sailboat (80-90 ft), sometimes just out into the abyss (we stop at 130 but one can easily go deeper.) Twice when going to the sailboat, I've actually incurred one minute of deco while I was already on the way back to shore. And I was pretty far along on the way back, too; it wasn't as though I waited until my NDL counted all the way down before turning the dive. Both times, I began swimming straight back up the slope toward shore with at least 5 minutes remaining. But I've discovered that, if I don't want to come up off the bottom to where I can't even see it, and I don't want to go into deco, I need to turn the dive with more like 10 minutes NDL remaining. (Of course, both times the 1 minute of deco disappeared before I reached the stop depth, and by the time time I hit 30 feet I was back to 99 minutes NDL. The safety stop countdown begins at 20 feet, and even though I don't stop, the timer clears before I get to 15 feet.) So what the heck even is bottom time vs. ascent? And how do you properly account for it without a computer?
Bottom time as originally defined by table users started when you began the descent and ended when you began the direct ascent to the surface. It had to be that way, because that was the only way to read the tables. Multi-level diving, such as you describe, was a problem. Once you realize that, and when you realize that you are using a computer and not a table, then traditional "bottom time" becomes meaningless for a dive like that. If you are logging the dive, just put in total dive time.
