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kucharek
2005-Jan-10, 11:14 AM
Yesterday I went to a newly reopened indoor pool (http://www.vierordtbad.info/0start.htm) just down the street where I live. Very convenient. It's one of the oldes indoor baths here, but completely renovated in the last two years.
Due to extensive exposure to BABB, I didn't simply relax there (note: make entry into YKYAABABBAW-thread), but made some observations I'd thought I can post here.
Here's the second one: (the first is here (http://www.badastronomy.com/phpBB/viewtopic.php?t=18849))
After spending most time with diving around (when I'm in a pool I'm usually more time under than above water) without some diving googles, my view usually gets foggy (above water), just as looking through some fog. When I looked at a very bright spotlight, I saw a small halo with rainbow colors around it, similar as you get when there is really fog.
Now that would mean that there are somewhere small droplets of water, but I've no idea where. I don't think they can be on the cornea of the eye, as this is wet and so droplets can't collect there.
It takes some minutes without diving until the "fog" goes away. Any explanations anyone?

Harald

Moose
2005-Jan-10, 11:19 AM
Droplets of air, most likely.

[edit: I wonder if the order of colors around the rainbow are reversed under water than what we ordinarily observe around sky?]

kucharek
2005-Jan-10, 11:31 AM
Clarification: I saw the halo when being outside the water, not under water.

kucharek
2005-Jan-10, 11:33 AM
Droplets of air, most likely.

[edit: I wonder if the order of colors around the rainbow are reversed under water than what we ordinarily observe around sky?]
If you've air droplets (bubblets? ;-))under water causing a halo, the colours should indeed be reversed, as the air is the optical thinner medium and so the effects of the refraction should be reversed compared with the usual case of water droplets in air.

Colt
2005-Jan-10, 03:10 PM
I think it might just be the chlorine messing with your eyes. It used to do it to me when I would dive in the pool without goggles... When I was underwater it was fine but coming out everything seemed kind of blurry until I blinked enough to replace the lost fluid. - Colt

Donnie B.
2005-Jan-10, 04:56 PM
Colt has it right. If a pool has high levels of chlorine, it directly affects the surface of your eye, producing the fog effect. It's temporary (although extreme levels of chlorine exposure can permanently damage the eye).

You can reduce the problem by keeping your eyes closed underwater (but that's no fun!)

Incidentally, most public pools keep their chlorine levels much higher than necessary, since they'd rather have too much than too little. I keep my home swimming pool at much lower levels, which are fully effective against organic compounds but much less irritating to the eyes. Lower chlorine levels mean little or no bleaching of hair and bathing suits, as well.

The general rule of thumb is, if you can smell the chlorine, there's either way too much or way too little (since what you smell is the "combined chlorine" after it reacts with organic compounds in the pool, rather than the "free chlorine" that's available for combining).

TriangleMan
2005-Jan-10, 05:54 PM
Yesterday I went to a newly reopened indoor pool (http://www.vierordtbad.info/0start.htm) just down the street where I live. Very convenient. It's one of the oldes indoor baths here, but completely renovated in the last two years.

That's a really nice pool! Wish there was something like that nearby when I was growing up.

Colt
2005-Jan-10, 06:13 PM
I forgot to actually look at the pool... And it is indeed nice. Mmm... Germany. - Colt

kucharek
2005-Jan-10, 06:35 PM
Yesterday I went to a newly reopened indoor pool (http://www.vierordtbad.info/0start.htm) just down the street where I live. Very convenient. It's one of the oldes indoor baths here, but completely renovated in the last two years.

That's a really nice pool! Wish there was something like that nearby when I was growing up.
I guess, on the Bermudas, there is no big need for indoor pools, isn't it?

Argos
2005-Jan-10, 07:03 PM
I forgot to actually look at the pool... And it is indeed nice. Mmm... Germany. - Colt

If it only had a bar on the side, it would be like heaven.

TriangleMan
2005-Jan-10, 07:46 PM
That's a really nice pool! Wish there was something like that nearby when I was growing up.
I guess, on the Bermudas, there is no big need for indoor pools, isn't it?
Yep, that's why I wished there was such a pool nearby when I was growing up (I grew up in Canada). Here in Bermuda access to a pool is not as big of a deal.

mike alexander
2005-Jan-10, 10:23 PM
Our current house has a pool with a pole shed enclosure (keeps the fir needles out). I've noticed that keeping the pH correct is as least as important as the chlorine levels to avoid eye and skin irritation.

And even though it can be a real pain in the kiester to keep it maintained, my wife and I love it.