How do "you" judge visibility?

[Tavi]

Originally posted by danceswithoctopus

UP's trigonometric calculations work well, but I don't like trying to use my calculator at depth

When you can do profiles for multi level dives on the fly in your head, Trig, Calculus, and Geometry without a calculator can't be that much tougher!

hmmm. maybe that computer is rotting my brain.


As to vis, I use the WAG method.

 

[rstone]

Use a really long stick

Ryan

 

[The Chairman]

Go here to find out how visibility is SUPPOSED to be measured...

http://dipin.kent.edu/SD Procedure.htm

Now, do you think your estimations are even close to this??? I know mine aren't, but what to do? Do I try to conform, or will I let my data be just for me.

 

[Stone]

When boat diving, if you come up the anchor line and people are boarding at the stern (and you know the length of the boat), you can improve your guess a little. Of course, the vis may be quite different near the surface than on the bottom.

 

[The Chairman]

SCIENTIFIC Wild Arse Guess...

 

[Uncle Pug]

Originally posted by Stone
Of course, the vis may be quite different near the surface than on the bottom.

This is often the case here in Puget Sound where viz in the upper 10 feet can be nil during the high cycle of the plankton bloom but actually very good at depth even though dark.

Today the plan is to survey a reef system for mapping and I plan to take a tape along so I should be able to get more than a guess on the actual viz.

 

[Stone]

When asked how he arrives at an estimate, one of the guys I work with is fond of saying "By anal extraction *".


"* I pulled it out of my . . ."