Day Time - Night Time Lighting [Archive]

carpguy

01-18-2003, 5:21 PM

I have 2x36 watts over my planted 30g, controlled by a timer to be on 12 hrs a day. I also have a 13w red moonlight, also on a timer. It comes on a little before the main lights go out and stays on until 12:30 am so that I can check things out in the evening. The 13w come back on about a half hour before the main lights, to give the fish a little wake up call, and then turn off after the big lights come on. Two timers from the Home Depot, maybe $15.

The red makes a nice moonlight, but the 13w is a little much on the 30g -- I have to block some of the light to keep it muted enough. Something a little smaller might be nicer, depending on tank size. I like the moonlight best mounted as far back as possible, mine is actually above the back rim -- all the decor gets nice dramatic shadows and looks more naturally nocturnal, rather than just badly lit.

JamisonBWolsh

01-18-2003, 5:25 PM

Red light as moonlight light??? Strange.... I would think BLUE light from LEDS would work best.... Looks alot better than red light as well! try it!

Sumpin'fishy

01-18-2003, 5:29 PM

It might look better to you, but his probably looks better to the fish. He's trying to simulate night and we've all talked about red lights being seen less brightly by fish.

JamisonBWolsh

01-18-2003, 5:37 PM

Well...just let me know the next time your in the wild and you see red light in the rivers and lakes. Moonlight matches more closely to blue light. As for fish seeing red...yes they see red as plain as day. That is just an urban myth. Example: I tried a red light and a blue light on my 60 gallon tank. My elephant nose wont go anywhere near the spot that the red light is. The blue light is fine and he swims throughout the tank when it is on. I took the red light OUT and added blue lights to all my tanks (3). Its like a whole new hobby. ALL my night fishes come out and swim with the BLUE light on. Works GREAT. Red light did not work for me at all. I have petricola catfish in my 60 and 20 gallon tanks. They hide all day and come out at night when the BLUE light is on. So this does not bother them at all.

Fish not seeing Red light is a MYTH!

Sumpin'fishy

01-18-2003, 5:53 PM

First off, Jamison, I didn't say they couldn't see it. I said that they see it less brightly (watt for watt). Also before you go around claiming you have found the truth and everyone needs to head your advice and disregard hundreds of other's experience, remember that you have had experience with this ONE SETUP using LED's. I wouldn't exactly call what you did a perfect scientific experiment. You need many, not just a few, setups with everything else the same and change only the lighting to check the reactions. You are always so eager to prove someone else wrong. I'm stating what I've heard countless times from experienced people. Let's not forget that you have been knicknamed "the boy who cried wolf" too! I don't mean this as an insult, just don't go stating your experience as FACT, just tell someone what you experienced. They will respect you more for being straightforward and honest. I followed very closely the thread you posted about your experience with your LED's. I think you did a great thing by testing for yourself, also. But I would hardly call this "the way it is".

Please understand that I'm trying to be honest and respectful of your opinion, but that you downed my remark. I'm not attacking you, just explaining my point of view. I have seen you in debates several times with people about your opinion, under the guise of "FACTS".

carpguy

01-18-2003, 6:00 PM

I was originally worried about the red having too much of a strange darkroomy kind of look to it. Emergency blackout lights kind of thing. Its not really that red, it has a warm but natural feel to it and I like it much better than I thought I would. But I am planning on trying a blue bulb as well. When I dig out my oldstyle camera I'll try to post pics of each, the digital camera can't catch enough of the low light.

As we discussed on a different thread, red is less visible than blue to a lot of fish. Blue wavelengths penetrate water better and deeper. Bottom dwellers, like catfish and my loaches, many of whom are nocturnal, probably don't bother developing full color vision and probably can't see red. This was a consideration when I picked the color bulb. My rasbora on the other hand, being surface-feeding insectivores, apparently did go and develop vision into the red spectrum. They react to the red target flashlight on the digital camera. The moonlight, being so short, acts as more of a spot than anything else -- the loaches wander around in it, but the rasbora "sleep" off to the side in an unlit area of the tank.

JamisonBWolsh

01-18-2003, 6:09 PM

your catfish does not come out in blue light? Interesting... Mine does come out... Red light does NOT look good at all IMO. Can we spell UGLY? Blue light acts in the same way as red light, but are nicer on the eyes as well..

carpguy

01-18-2003, 6:20 PM

Hi Jameson,
I honestly like a lot of the rolling debates you bring to the board and I've been forced to go look up a lot of things that I wouldn't have learned otherwise just because I needed to explain to myself why I thought something sounded wrong. I think, with your obvious entusiasm, you have a lot to contribute. You're style is a little combative -- I think if you'd ease up on the right-and-wrong and stay more with the "this has worked for me" and "this why I made this choice" end of it, you'd have an easier time.

Fish, much like us mammals, vary. In size, in shape, in diet, in details of the construction of their eyes. Some see red, some don't. A lot of the bottom-dwellers, especially the nocturnal ones, don't. Several feet down, in the bluish moonlight, what need would they have for it? Red is frequently used as a nightlight for this reason. Blue would seem more naturally moonish to me as well. The red looks much more natural than I'd anticipated. It works. I'm going to try the other for comparison sake as well. Will post results.

JamisonBWolsh

01-18-2003, 6:43 PM

I was looking for a few facts on the web, I couldnt much find any eithor. Just conjectures. Such as color light does not penetrate more than 3 feet deep. The light that does penetrate further then 3 feet deep is blue light. If fish live deeper then 3 feet, they would not be able to see those colors. especially RED LIGHT, which disperses fast before it reaches to any depth. In SALT water, that is correct. HOWEVER, MANY freshwater fish live in the first 3 feet of water. So, in theory, they should be able to see the red light because they have been "raised" in those conditions. For those fish that live deeper than 3 feet, they would not "see" the red light.
As for which is better? I cant find a source at this point that says RED is Less stressfull to fish as a BLUE Light or the other way around. All I can say is Fish need a light/dark cycle to lower stress.
Can anyone tell me if having red LEDS or Blue LEDS cause stress to fish? If they can "see" the light....does this interupt the light/dark cycle? Im not talking about BRIGHT red or blue light....Just a few LEDs....
On the internet, I have seen pics of Red light tanks and Blue light Tanks. Im still trying to find some factual info on blue and red light...

pinballqueen

01-18-2003, 7:03 PM

Let's get into physics and wave formation here for a sec...thinking back to astronomy class....

Blue light resonates at a much shorter wavelength than red.

Given that fact, the doppler effect states that the further a short wavelength travels, the longer the wave becomes as viewed/heard/detected from distance. In essence, if you are standing far enough from a blue light source, the light waves will be bent by the atmosphere between here and yon, eventually to the point of being in the red or infrared spectrum.... this is known as "redshifting".

While blue light waves are much more intense than red ones are, the red waves, with their slower rate of modulation, will actually travel deeper into things than the shorter, faster waves will.

Think back to your friend's car stereo system.... If you are standing right next to the sound source, you hear all the highs and lows. The further you get away from the speakers, however, the less of the high-pitched parts you will hear, eventually only hearing the "thump" of the bass. The higher pitched sounds have a much shorter wavelength than the low-pitch sounds do. Which one travels further?

Knowing all this, it is only reasonable to think that in a natural deep-water environment, the red light would penetrate the water much deeper than the blue would, even though the blue end of the spectrum is more intense to the human eye. Bear in mind that the light reflected from the moon is white, or full-spectrum light. Only the red parts of the light, the part of the spectrum with the longest wavelength, would reach the bottom of the lake. As for whether the fish sees this light as being "red" or just being "light" is anyone's guess. For my money, if you are going for a "natural" deepwater environment, red would be the logical choice, ugly or not.

Here's the really neat part about it... did you know that when you turn the lights down really low, red is much easier to see with our eyes than blue? Try it. Take a red piece of constuction paper and a blue piece of the same intensity colorwise, and lower the lights down.... the blue piece will begin to look gray long before the red does (we humans lose our color vision, starting at the high-wavelength colors, whenever we are in low light situations... just an interesting tidbit...)

carpguy

01-18-2003, 7:16 PM

I have an interesting book called Understanding Tropical Fish, very good, about $15. It has a whole chapter on the senses. In the section on sight it talks about rods and cones. Rods are responsive to light intensity, while cones are responsive to wavelength (color). It explicitly says that most fish have color vision. But (always a but) "The ratio of rods and cones… vary considerably between the species… nocturnal fish… may have large eyes… and an abundance of rods in the retina… a daytime-active fish… perceives color because of the greater number of cones inits retina." At some level its just about real estate: the nocturnal fish benefit most from having a lot of rods and fewer cones. (Perfect example of having to go look up something interesting).

So what does that mean in terms of blue and red (both colors)? The book doesn't say. Blue light, penetrating more deeply, would have greater intensity (rods) at depth. The red makes it to the bottom of my tank. Is there a difference in our very small little tanks? Dunno.

I think light behavior in water is similar if not identical in salt or fresh.

A lot of my fish are stream and swamp (shallow water) fish. A lot of other commonly kept fish come from lakes and rivers where the bottom is often deeper than 3 feet. Some of these fish may spend most of their time near the surface. Or near the bottom. Or live in murky water. Or in shady rainforests. Or may need to worry about predation from birds, or not. I think there is probably a lot of variation from species to species on what they can see. My rasbora and barbs definitely react to red. My loaches seem oblivious, but then the loaches always seem oblivious… they're quite mad.

JamisonBWolsh

01-18-2003, 7:18 PM

Pinball: Well..the point is which light as a "night light" will cause LESS stress on fish at night? Red or blue? BTW.... you are correct in your theory on light. HOWEVER...in WATER.. blue light actually penetrates alot deeper in the water then red light does. Red light can go no deeper then 3 feet...only BLUE light can penetrate at deeper depths,...

Sumpin'fishy

01-18-2003, 7:24 PM

I don't have any experience to say any more about the color shifts/ or visibility. I do want to give up some props to Jamison for always having an opinion (which isn't a bad thing), and most importantly for doing LOTS of research on anything that interests him. I would definately say, Jamison, that you have forced out alot of great detailed info on topics that probably would not have come out normally. I agree with Carpguy that your wording probably rubs alot of people the wrong way sometimes, but I'm starting to see a genuine search in your for the truth. You are not willing to just take what you hear once and hold on to it as fact. I really think you have alot to offer all of us on AC. Also I really would like to thank you for not taking personally what I was saying to you. I didn't know how to word it any differently while getting to the point. I was kinda scared you would blow up on me about it. It shows alot of maturity (at any age) to be able to do that.

Your research into the LED area of nightlighting is something that was well-timed on this forum. Not many people have done ANY real personal research into this. I think it was a great idea to try, whatever the outcome. You had a problem with jumpy fish----you sought out a way to fix it while maintaining a beautiful view. Good for you! Just don't want you thinking I hate your input or anything:)

JamisonBWolsh

01-18-2003, 7:25 PM

Originally posted by carpguy
My loaches seem oblivious, but then the loaches always seem oblivious… they're quite mad.

You mentioned this before :) I bet they are your favorites? What type are they? I only use 2 LEDS in my 60 gallon and 1 blue led each in my other tanks. So, its not adding a WHOLE bunch of blue...just enough to see the fish... I would suggest ANYONE interesting in a moonlight effect- whethor blue or red- use a LED. The miracle Beam system is cheap and worth the money. TRY IT! If you dont like it...well.. Walmart has a GREAT return policy! :)

Try a blue and a red and which ever you dont like..just return back to the store for a refund :)

pinballqueen

01-18-2003, 7:27 PM

Originally posted by carpguy

So what does that mean in terms of blue and red (both colors)? The book doesn't say. Blue light, penetrating more deeply, would have greater intensity (rods) at depth. The red makes it to the bottom of my tank. Is there a difference in our very small little tanks? Dunno.

I think light behavior in water is similar if not identical in salt or fresh.

.

Blue light actually doesn't penetrate as deeply as red does. It's like a really rapidly spinning top... it slows down when it encounters resistance. Light does not travel as well through water as it does through air. Whenever a blue light and a red light of the same intensity are shone into the same patch of water, the blue light wave would have to resonate several thousand times more often than the red one would to reach the other side. Red is much more efficient, taking much less effort to travel the same amount of space. Therefore, the blue light will slow down.... redshifting in action.... (The visual effect might not be visible to the naked eye when we're talking about the very short distance involved in a fish tank). Red light exhibits a similar redshifting effect, moving into the infrared spectrum. Why do you think they use infrared led's in remote controls for tv's? The infrared light will travel further with less degradation of the wave than a visible light or a microwave would....

JamisonBWolsh

01-18-2003, 7:45 PM

Thanx sumpin!

With My fish, Blue light is the best..for yours? who knows? experiment. Some fish like blue..while others like Red. My fish like Blue. I also have barbs and like the elephant nose....does not care for the red light.

As for the debate about red penetrating further then blue.. check these links out..:

http://www.notcatfish.com/equipment/lighting.htm
says "In seawater, even at shallow depths (<5 metres), red light quickly becomes indistinguishable and at greater depths blue-green light prevails. ... still maintain the ability to see blue wavelengths better than red."

I will check out more websites in an hour...Dinner time!

NJ Devils Fan

01-18-2003, 7:50 PM

I didn't feel like reading all those long posts because I'm too lazy now. I just wanted to say that I am looking for a 100w bulb because I plan on having plants and the bulb I have now is only 40 watts. Maybe, I will get the old lid I have in my attic and put it behind the light I have now so that it's like a wake up for the fish before the big blast of light. That lid is Incandescent(sp) so it has 2 sockets where I can plug in regular bulbs.

pinballqueen

01-18-2003, 8:02 PM

One thing to keep in mind is that water, in very deep layers, is blue-green. (hence why the ocean is blue; that, combined with other chemicals and compounds that are in seawater...). Blue light degrades faster than red light does due to the shorter wavelength, it just has a lot more energy to travel between what's in our "visible" light spectrum and what isn't. Red light only has one color to "jump" from being something we can see to something we can't see. Blue has at least 5 colors to travel through before it is slowed into an invisible light wave at the infrared level.

Logic would dictate that since water is blue anyhow, the blue light will penetrate the layers easier even though the red light wave is more stable because the water reflects blue light, bouncing it further into the depths.... so, I respectfully retract my statement. I have learned something new today. Thanks for arguing with me, Jamison. I'm always on a quest to learn new things and come to new conclusions. Anything that broadens my horizons is welcome.

I will hold on to one thing though. If light were traveling through a liquid that was naturally, say, orange or red, (take liquid sulfur for example), the red light wave would travel much further than the blue one. Also, if the liquid were a color that falls in between these two, say, something yellow (such as uric acid), or is truly clear, (sorry, nothing comes to mind) then the red light would penetrate further than the blue one.

carpguy

01-18-2003, 8:06 PM

PBQ,
As ever, really interesting input. Like Jameson, I'm a little confused by the red blue penetration thing. Reefers use very blue lights to mimic the lighting at depth. Its not red down there. What you have to say about red makes perfectly good sense though -- here in sunny NYC I get nightly reminders of the carrying power of a 14" bass speaker. :mad: Good analogy.

My point about the red and blue for nightlights though was this: if the daytime fish can see either, and the nocturnal fish can see neither (mostly rods, looking at intensity not color) then does it matter at all which color we choose?

As for the stress, my moonlight is nominally less than 20% of the wattage of the main lights and its masked back to boot. Probably less than 10%. I do find it a bit too bright for a 30g and may have to look into the LEDs. The light also acts more as a spot than anything else, so there are always dark areas for fish to shelter in and all lights are off for at least 8 hours at night.

JamisonBWolsh

01-18-2003, 8:15 PM

Nj Devil: try a timed desk lamp... to turn on before the main lights. a suggestion made to me on a prior post. Better yet.. Have a few LEDs in the tank so it wont go from pitch black to bright light.

Carp: I am currently using the miracle BEAM system. It costs 21.95. Basically, it has a LED that you would place on the glass top shining down (more natural). It does have a spot light effect on whatever you shine it down on, but it does create alot of shadows and "dark areas". It mainly lights up a small area.You can also point it at the back of your tank "dimming the light". I have 2 on my 60 gallon tank. So..there are PLENTY of Dark areas...

I keep my LEDS on 24 hours a day..

pinballqueen

01-18-2003, 8:16 PM

Originally posted by carpguy

My point about the red and blue for nightlights though was this: if the daytime fish can see either, and the nocturnal fish can see neither (mostly rods, looking at intensity not color) then does it matter at all which color we choose?

As for the stress, my moonlight is nominally less than 20% of the wattage of the main lights and its masked back to boot. Probably less than 10%. I do find it a bit too bright for a 30g and may have to look into the LEDs. The light also acts more as a spot than anything else, so there are always dark areas for fish to shelter in and all lights are off for at least 8 hours at night.

I've got the LED's in my tank as well, mainly for my aesthetics. I don't think it's a big deal which color you use, just whichever seems to work better for your situation. The blue lights are brighter to me than the other colors, in fact, they burn my eyes, so I have them pointed where they are not in my direct line of sight (however, I have distorted color vision, so I am not sure whether they actually are a higher-output light or not... my vision is far from normal, so your experience may vary).

The only thing you can do is try it and see if you like the results and if your fish like the results....

NJ Devils Fan

01-18-2003, 8:21 PM

Jamison, what are LEDs(sorry, I don't have time to read through the posts because the devils game is on)

carpguy

01-18-2003, 8:22 PM

Ah the ol' cross post. :D

PBQ, I still can't reconcile the longer wavelength thing with the blue penetration thing. I know its blue down there, but what you had to say about the wavelengths made sense to me, even if it seems to run counter to it. Blue has only one color to "jump" before it goes ultraviolet, but I'm not really sure why that's important.

Just an interesting side note on color: we're best at distinguishing colors in the blue-green section of the spectrum. For some reason our eyes make the finest distinctions in that area.

carpguy

01-18-2003, 8:27 PM

NJ D, LEDs are Light Emitting Diodes -- those solid pieces of plastic that give off light on stereos and what not. I think they finally can make them all across the spectrum, but the older ones were always red.

With that incandescent hood you were talking about, you could use some 11w screw in flourescents -- the heat output would be much lower. If I ever do a large tank I'll definitely install some twilights as well, but for know the moonlight does double duty.

JamisonBWolsh

01-18-2003, 8:29 PM

Devils winning?

Anyway, its a relatively new lighting concept not only in the aquarium industry...but in our everyday lives. They Use VERY little energy and provides an intense light with NO HEAT emessions! Now colors are available in different colors. For night lights, a few wont add a whole bunch of light, but will add just enough to view. They are about 1/4 inch "bulbs". Someone is actually trying to create a Tank light with a few hundred of these bulbs To create a "NO HEAT" Lighting system.

anyway..they cost 7.99 per light at walmart (6.99 at bigalsonline) and the system itself is 21.95

7.99 is for per lighting UNIT. The bulb itself is extremely cheap

JamisonBWolsh

01-18-2003, 8:34 PM

Here is an example:

http://www.miraclebeam.com/hilite.asp

This tells you everything about them and what they look like. I would personally point it "down" because it does look more natural. My Leds are actually shining through the glass top and into the water. Looks really neat when I position each light on my 3 tanks at the correct angle where the position of the moon would be shinning down on each tank the same... :)

BTW: they are like the LEDS from your remote controls or stereo BUT HIGHER TECH and BIGGER!!!

pinballqueen

01-18-2003, 8:37 PM

Originally posted by carpguy
Ah the ol' cross post. :D

PBQ, I still can't reconcile the longer wavelength thing with the blue penetration thing. I know its blue down there, but what you had to say about the wavelengths made sense to me, even if it seems to run counter to it. Blue has only one color to "jump" before it goes ultraviolet, but I'm not really sure why that's important.

Just an interesting side note on color: we're best at distinguishing colors in the blue-green section of the spectrum. For some reason our eyes make the finest distinctions in that area.

Point one: blue light would have to resonate FASTER to head up to the ultraviolet spectrum.

Point two: the finest distinction might be in the blue end of the spectrum, the easiest color for the human eye to see is hunter's safety orange (which is why they use that color...). Another technical tidbit....

JamisonBWolsh

01-18-2003, 8:49 PM

This is a GREAT article that i think you will enjoy pinball.

http://www.animalnetwork.com/fish2/aqfm/1999/july/features/2/default.asp

It pretty mentions everything that Pinball said earlier. Blue does go deeper then red, but other colors as well.. read the article. Very interesting...Too scientific for me though :)

It talks about Corals.. but light is Light...

aljen

01-18-2003, 9:54 PM

This lighting arrangement cost about $175 to construct. ($125 for AH Supply, $25 for 3 timers, $25 for hardwood)http://home.pacbell.net/aljen/18tallcomposite082901.jpg I have a 13w red bulb that runs 2 hours in the morning and 2 hours at night. I have a 13w 5000k bulb that runs about 12 hours. I also have a 36w 6500k bulb that runs about 6 hours in the middle of the day.

IMO, the sunrise/sunset effect is NOT worth the effort.

NJ Devils Fan

01-18-2003, 10:13 PM

Jamison, the devils won 5-2. They scored 18 goals in 4 games. I hope the scoring keeps comming.

I will put that incandescent hood on a table next to the tank and have it on a timer so that it goes on about 20-30 minutes the main bulb goes on.

carpguy

01-18-2003, 10:31 PM

That was an interesting article JB. For our purposes, here is the relevant info:

"Water absorbs longer wavelength light to a greater degree than short wavelength light. In other words, the first wavelengths absorbed are infrared and red wavelengths…(then infrared and ultraviolet, other colors) As one approaches 30 meters or 100 feet, the only light that remains is between 450 nm and 550 nm (blue and green)… Note that both blue and green remain and that both shorter and longer wavelength light is attenuated… It is an inaccurate generalization to suggest that only blue remains. It is more accurate to describe the light field underwater as lacking red, rather than consisting only of blue… Even at 30 feet, most of the visible spectrum is still present, with only red light over 600 nm significantly attenuated."

As far as the moonlights go, I'm still wondering: if the daytime fish can see either, and the nocturnal fish can see neither (mostly rods, looking at intensity not color) then does it matter at all which color we choose?

Aljen,
Great looking tank! :D Very simple and elegant. What is that outcropping? Rock, cork, synthetic?

I don't want to keep the lights on too long (algae), so the moonlight is really for my own viewing pleasure and worth the effort. Cheaper than getting better blinds for the windows. The twilight is just a simple adjustment from there: I don't think I'd bother with a separate twilight rig.

JamisonBWolsh

01-18-2003, 10:47 PM

Originally posted by carpguy

I don't want to keep the lights on too long (algae), so the moonlight is really for my own viewing pleasure and worth the effort. Cheaper than getting better blinds for the windows. The twilight is just a simple adjustment from there: I don't think I'd bother with a separate twilight rig.

I know with LEDS, there is not enough light present to build up algae of any type. Having the moonlight on when the main lights come on does not stress out the fish from the change from pitch black to bright daylight. Of course, if you have sunlight entering the room, I think that should be fine. I persoanlly do not...so the moonlight helps my fish adjust..

RTR

01-18-2003, 10:58 PM

pinballqueen and JBW - I think you need to go back and review Doppler Effect and red shifts - they deal with the speed of the light source relative to us, not with any modulation of the light in the intervening distance. Unless your light fixture is approaching or receding at relativistic speed, its output color is not stretched or shrunk with red or blue shift This is not the effect significant in water penetration of various colors of light.

In water, red penetrates less than blue (as carpguy detailed), not the opposite case as has been held in this thread. If it were as presented here, the seas would appear red, not blue.

Deepwater fish and nocturnal fish perceive red light poorly or not at all, so it is effective for night viewing of such so long as it is really red and not too intense. Blue light can be a simulation of moonlight, again with the same intensity stipulation, so may well be accepted as "normal" by nocturnal fish also. IME & IMHO, intensity is more important than which of the two colors is chosen. But for night viewing I use red, very low wattage or very heavy filters.

carpguy

01-18-2003, 11:16 PM

Jamison, I just realized your name is "Jamison" not "Jameson" -- I must hang out in Irish bars too often… :D

The tank is in a west facing room, so the morning light is pretty modest but I like to keep the main lights more or less on a daytime schedule: 8:30 to 8:30. They are the algae concern. In a darker room I might slide the day around to 11 and 11. The moonlight isn't an algae concern and stays on until 12:30 am. I can check out the tank at night… Back on at 8am, back off at 9am to help smooth out the daylight transition. Its in the bedroom: I find the sudden lights on at 8:30 a little jarring myself.

As RTR just mentioned, I try to keep the intensity down on this: the 13w by itself (without a reflector) is still too bright IMO for a 30g. I have it masked with a few strips of dark paper under it and will probably try to find an acetate filter for it at some point.

And I think by now we have pretty much covered this subject in depth and in detail…

pinballqueen

01-18-2003, 11:24 PM

Originally posted by RTR

In water, red penetrates less than blue (as carpguy detailed), not the opposite case as has been held in this thread. If it were as presented here, the seas would appear red, not blue.

Originally posted by pinballqueen
Logic would dictate that since water is blue anyhow, the blue light will penetrate the layers easier even though the red light wave is more stable because the water reflects blue light, bouncing it further into the depths.... so, I respectfully retract my statement. I have learned something new today.

Yes, sir. If you will notice in a previous post, I retracted my opinions upon further consideration of the specifics of this discussion. I had been arguing from the standpoint of wave reactions through a colorless substance. I had forgotten that water is not entirely colorless, but is in fact blue.

carpguy

01-18-2003, 11:40 PM

In all fairness the quote was from an article JB found.

PBQ, your doppler argument made sense but didn't seem to jive with reality. We eventually got to the bottom of it. RTR did seem a little terse, but its a forum, it happens when people type. Let it go…

And not that this really needs to keep going on until dawn (moonlight should be shutting off any minute now), but water isn't blue, its perfectly clear. The blue is just behavior of light in a medium, not a characteristic of the medium.

Have a good night all ;)

EDIT: 3 pages on this, good grief :rolleyes:

pinballqueen

01-18-2003, 11:50 PM

Originally posted by carpguy
And not that this really needs to keep going on until dawn (moonlight should be shutting off any minute now), but water isn't blue, its perfectly clear. The blue is just behavior of light in a medium, not a characteristic of the medium.

I'll not go into details to save people from death via boredom, but I and my chemistry books respectfully disagree with you as to the "perfect clarity" of pure water.

Who'd a-thunk this would've been such a lively discussion....:D