My first relatively deep solo dive...

[ClayJar]

First I went diving in a cove in the lake. Cruising just off the bottom at 50 feet, my mask started fogging. I flooded and cleared it, but it was still fogged.

Then I noticed that I couldn't see my hands - my mask wasn't fogged, the viz was 'bout 6 inches. Just about that time I ran right into a tree trunk. THUNK! About knocked myself out! Kinda freaky being in near-zero viz solo. I think the basin accumulated silt and it just sat there on the bottom.

I had a dive similar to that a couple weeks ago. There was an area with bottom depths in the 15-20' range that was completely obscured by this superfine suspended silt. It started playing tricks on my head -- it looked exactly like my mask was fogging up.

I figured it out of the second dive. By holding one of my blue-gloved hands just in front of me, I could watch it to see that my mask was crystal clear, even though the suspended silt made my eyes disbelieve. (The detail I could pick out on my dry gloves was surreal. I suppose my brain was comparing it to the extremely low contrast surroundings and amping it up a bit, but it was a strange feeling.)

The vis was decent once I got below 20', and it was *excellent* at depths in the 70-100' range (where temperatures were around 45°F). Below 100' and above 20', it was a dark silt-out and a bright silt-out respectively.

 

[captain]

Years ago I got a hit of vertigo durning a solo in bad vis. No visural reference will sometimes cause it. In aviation it's know as spatial disorientation. It can happen when flying at night or in clouds. It usually goes away in a few seconds but basicly you feel like everything is spinning around you and you can't tell up from down.

 

[MikeFerrara]

your depth should match your viz, that is my motto.

That might work in Hawaii but in much of the waters of the rest of the world that would rule out descending in the first place. LOL

 

[redacted]

When the vis gets that bad, most divers are solo even if they have a buddy.

Always trust the compass. If you get to a point where you don't trust it, abort the dive. It's no fun to get lost when you are solo. But it is really bad to get lost when my wife is my buddy.:shakehead

 

[b1gcountry]

That might work in Hawaii but in much of the waters of the rest of the world that would rule out descending in the first place. LOL

Yeah, that's exactly what I was thinking. I just got down to 88ft solo this weekend to see the (missing) tool truck at Jordan Lake, and vis was only about 15ft at the surface. Went down to 2-3' below the first thermocline, and got so dark below 80' that I had to turn around. If you are comfortable in low vis, and expereinced in it, there is no problem if conditions are otherwise good.

Tom

 

[Tigerman]

Speaking of deep and dark.. Seems to be a lot of that going around lately..
Less than 24 hrs ago, I did one myself.
the intention was to go down to approx 20 meters in a freshwater lake where I live to look for and hopefully retrieve a fairly new outboard engine that had fallen off a boat. The supposed to be knowledgeable about the area said it was supposed to be approxmately 20 meters, but going down to 10 meters there was no way to see the bottomn. 15 meters and still no sight of the bottomn and it was basically pitch black. The lake has a lot of black mud many places and this seems to have been one of them. Interesting enough, I was thinking "Im supprisingly cool with the fact that I can see nothing". When I got to 20 meters there was still no sign of the bottomn, but I could see the rope (That the guy who lost the engine said to be approx 20 meters) continuing further down and still no sign of the bottomn. Having dived in the same lake before, knowing about the mud there is, I did bring a UK C8 LED light, but it didnt help me much in finding the bottomn. Based on my air consumption and the depth I had planned I knew I could do 20 minutes at 20 meters with spare air and had planned 20 meters max, i did the responsible thing and went back up.
Dont think I wanna be down there...

 

[DivingCRNA]

Years ago I got a hit of vertigo durning a solo in bad vis. No visural reference will sometimes cause it. In aviation it's know as spatial disorientation. It can happen when flying at night or in clouds. It usually goes away in a few seconds but basicly you feel like everything is spinning around you and you can't tell up from down.

I got that on my first ever night dive. It was in a lake in Minnesota and I got in a zone where I coudl see neither the bottom nor the surface. It really weirded me out. It was during my AOW class. I loved ocean night dives, but am still a little skiddish on lake night dives.

 

[Timeliner]

So ... DocHarry.. From the looks of things you have been in a plane before.
Many times ! Like Captain, This vertigo thing is something I experience and have actually learned to enjoy as a sort of diving rush. I have found that "mentally" turning into the spin seems to correct the problem quickly.
I can see from a performance stand point it is a danger and what can a top notch fly boy tell us about it that might bring it into control faster

 

[Doc Harry]

Vertigo is often preciptated by a loss of visual reference cues, e.g., loss of visual reference to the horizon.

In such a situation, other than regaining some visual reference there is little one can do to prevent vertigo. Once the visual reference is regained the vertigo should subside.

If one is experiencing vertigo despite a visual reference, you should try to minimize head movement (especially in the up/down movement plane). Any head or eye movement should be very slow. Face forward in the direction of travel. Try to stop moving altogether if you can to allow the vertigo to subside.

Of course, this discussion does not apply so much to medical causes of vertigo such as a ruptured ear drum, stroke, etc.

 

[Tigerman]

There is also always one visual reference when you scuba dive, unless you break one of the basic rules.. Your air bubbles. They will always be traveling upwards, so if you follow them, youre going to the top.. It needs to be completely zero visibility before that reference is gone, which means youll practically need to be blind..