Natural light at Sunrise and Sunset

[bvbellomo]

What does a sunset/sunrise look like without artificial light on a coral reef? I am interested in about 10 meters down. This should be the same in any large body of water, not just reefs.

I am a diver, but have never dived at sunrise or sunset. I am asking because I also have a large reef tank. I know this might not be the most appropriate question for this forum, but it is the most appropriate audience for my question. I know this is a crazy level of detail to be concerned with, but reef tank owners are crazy people.


Hobbyists tend to shift colors towards actinic/blue/purple if we do anything at all when our lights go on and off. This almost makes sense - the steeper the angle of the sun's rays, the more water they pass through, the closer the color should be to being deeper down. However sunlight gets redder above the ocean as the sun sets, so getting rid of actinic first makes sense too.

 

[rob1967]

It's going to be pretty dark. Because of the angle of diffraction of light as it passes from air to water, the rays of the sun do not penetrate water as the sun gets low on the horizon. So it is basically a night dive for say about an hour before sunset (depending on latitude).

 

[Amlez]

I'm also new here and can't help much with the main question you've asked, but at the risk of hijacking your thread, I couldn't resist taking up on this :-

I know this is a crazy level of detail to be concerned with, but reef tank owners are crazy people.

Ain't that the truth .... !!

I'm a 'reformed' reeftanker - gave it up 5 years ago when the front pane on my little tank cracked & I lost the lot :depressed:

On the bright side, this is what led me to UW photographer - used to blow bubbles to collect new specimens for the tank (yes, completely legal in my part of the world ),
but now planning to blow bubbles in the pursuit of photographic genius .....

Here's a few pics of my system before it crashed - I hope to become a better UW pic taker than I was topside!!

 

[jcclink]

Go hack somewhere else. You're so totally off topic.

 

[Kharon]

My experience is pretty much black and white without additional lighting.

 

[Amlez]

Whoa - thanks for the welcome JCC!! - (and apologies to the OP for any offence?)

FWIW - if you're trying to replicate sunrise/sunset in your tank (or soften the stark blast of 100's of watts of halides coming on/off), a 'moonlight' (small 6" neon blue fluoro?) on a timer works fine - but I guess you already know that.