Blue LEDs

[cabezon]

After reading a DIY and some other things about moonlighting, I tried some things. I wanted moonlight to discourage my boss from leaving all the lights on in the tank when he leaves. he likes the light for a nightlight. I come to work and all my fish have jitters and the algae are having a field day.

I went to home depot ad found some white led night lights and plugged 5 of them into a surge protector, voila light.

Tonight I went to sam's. They have blue LED xmass (or Hanukkah lights) 3 strings of 60 bulbs for $15. i will try to attach them to something and put some around the back for fill. Fish Disco! and someone mentioned to put them at 45 degree to the water for shimmer. I will keep that in mind. Stay tuned after thanksgiving for pix.

Shaw

 

[tropicalfish]

Cool!!
I just used mini Christmas lights that are blue. I might change to LED soon for the minute energy savings lol...

 

[Sicklid]

I am not sure, but LEDs cannot really be "aimed" any specific degree to the surface because they are not beams of light like a lazer. They are round as far as I know and emit light in a hemispherical way, so anywhere you put them they will most likely shimmer...

 

[wierdkid]

actually leds really only project light in about 30 degree field (15 degrees from center in all directions). if you have a led light and point it at something the light projection is quite small (on the bottom of my 29 gal tank each led projects light on an area about 6" in diameter

 

[tropicalfish]

But it also depends on the LED you get...
My LEDs, I took out of my broken digital camera's autofocus lamp and then LCD lightup...
When you take it off the focuser thingy the light comes out in all directions except the bottom..... If you know what I mean

 

[Guest]

someone mentioned to put them at 45 degree to the water for shimmer

I've had the moonlights in a fixture before that where aimed straight down into the tank and was still able to have the shimmering water effect on the substrate. You might not have to go threw the trouble of adjusting them the way you want to. HTH

But yeah, we want pics!

 

[cabezon]

I finished the first one, but my camera is in mexico and it is not dark out. I took a strip of wood and drilled 60 holes through the length of the strip. i thought I was going to use glue to hold the lights in place, but no glue would set in time. so I grabbed my bag of rubber bands and banded each light down. it looks hilarious. I also drilled the holes at a 45 degree angle. from what it looks like with these lights, most of the light comes out the side, so it is not overly bright as I thought it might be. it looked great at home with the 5 gal, so I cant wait to see what it looks like, its just shy of the width of the 55 gal.

 

[quixand]

Can anyone post what is needed to do this using parts from Radio shack?

I know I need the LEDS, which resistors do I need, and will any AC adapter work?

I want to wire 8 blue leds in a chain type config, and install them in my hood.

Thanks!

 

[tropicalfish]

I don't think you need a resistor at this point. Wire the LEDS in a parallel pattern, and say each LED takes 2 volts, set the adapter to 2 volts. If not, try a little bit higher. If you go too high, you blow the LEDs, and you can't use them anymore.
(not literally blow, just it won't work anymore)

 

[quixand]

Hmm...I was always under the impression you needed resistors. Can anyone else confirm?

 

[JProx]

i don't have time to get into details, i will later today, but yes having resistors is a very good idea, for various reasons.

1. we live in a world of electronical theory, not law. so having any 'protection' in a circuit is a good idea, and resistors tend to be the cheapest form of it. it will protect the led from over-voltage/current problems, will trim the incoming voltage to the nominal requirement of the led.

2. transfomers do usually flucate, and everything has a tolerance. just because the transformer says 4volts out, doesn't mean you will have a clean 4volts out. they are allowed to be off +/-10% usually, you might get 4.4 volts or 3.6 volts out of it and thats acceptable.

3. since transformers are not perfect you will need to regulate the voltage for the leds through a resistor. you can wire up a circuit to use 1 resistor total, or 1 resistor per led. since resistors are sold usually in 5paks, you might as well be more cautious than neccessarry and use 1 resistor per led.

you can use any D/C transformer you like, but will have to change resistor values accordingly. i have boxes full of old transformers from cd players, kitchen gadgets, etc laying around the house and usually thats what i use and suggest to people.

 

[quixand]

JProx,

Thanks for the theory, I've never been one for electronics that much, but I find it very interesting. (albeit somewhat confusing)

So my question is Radio Shack carries two types of LEDS.

1) Blue 2600 MCD intensity, T-1-3/4 (5mm) size LED $4.29

or

2) Blue 5mm Blue LED $3.29 and IIRC was a 800 MCD intensity LED

Which one do I want to use, and which size resistors should I pick up?

I can use any type of project wiring to wire it all together, a 4 volt capable wall adapter..... I'm ready I think, just need to know with which LEDS to choose and which size Ohm resistors to pick up. I'll do a DIY how-to once I get everything situated.

Thanks again for the help guys!

 

[godzilla]

if you can wait, I bought 12 of these for .59 each, radio shack must be smoking some real good stuff to think people will pay 4.29 / LED, thats insanity!!!

http://secure.llamma.com/catalog/product_info.php?products_id=237

I also used this page to figure out what resistance I needed, I am doing 9 LED's, attached is a diagram created by this website

http://metku.net/index.html?sect=view&n=1&path=mods/ledcalc/index_eng

This site should help you get exactly what you need for DIY moonlight

 

[quixand]

Many thanks for that link. Just put in my order. =)

10 LEDS w/ resistors cost me 6 bucks. + $5 worth of shipping.

You saved me like.... 30 bucks. many thanks

 

[JProx]

forgot to include this link earlier.. it seems an explanation over the principles isn't need anymore.

http://www.lsdiodes.com/shop/index....Path=1&zenid=35e6e589e611b60492cb7650af41cac1

.45cents an led, thats where i load up on mine.

there's usually some confusion over the MCD rating of leds. most lights are rated in their Lumen output, but leds since they incredibly low power use a different scale - milli candela. there's no direct, conversion from lumen to milli candela. the scale is 1candela is equal to the same light out put of a candle. milli is a number scale meant to show the thousandths (.00x) decimal place. so those blue leds are 5900mcd = 5.9 candelas about 6times brighter than 1 candle. i usually suggest 5 leds per 4 feet of tank (lengh of tank) for moonlights. the white leds they sell (the 12,000 mcd) are ridiculously bright, you can't even look anywhere near the led as its too bright. i was playing around with 3 of them, and they were bright enough to illuminate my entire 2 car garage, not bright enough to do work, but bright enough to identify everything in the garage.

pretty much all regular 5mm leds or smaller have a 30degree light emitting area, what that means is you will get the 'spotlight' effect on your gravel, sand, etc. i usually go to homedepot and buy some fluorescent light diffusion panels (opaque plastic that diffuses light) and that eliminates the problem, if you don't like the effect. i personally like it especially when you have built a reef layout with caves, and aim the leds to showcase those areas, or other high traffic spots.

if you guys happen to have questions on electronics, let me know i will help you out where i can.

someone a while back mentioned something about gluing leds in place, i find hot glue works the best. i will drill a hole about 1/8 to small and the bottom lip of the led will rest on the top of the hole, and i will apply the hot glue over the base of the led, and its leads. it doesn't conduct electricity, and is non toxic so you shouldn't have any problems using it. just remember to cover any exposed leads/wire with liquid electrical tape (or more hot glue) just to reduce any potential problems.

 

[TwoHobbies]

You can also sand the end of the LED off if you want to get rid of the spotlight effect.

 

[godzilla]

You can also sand the end of the LED off if you want to get rid of the spotlight effect.

please explain!! im intrigued by this....

 

[godzilla]

i found this, but cant read it. its a comparison of sanded to unsanded...i like it!

http://www.ackw.dk/div/billedlys.htm

 

[tropicalfish]

Basically, you just sane the finish of the LED so it is like frosted glass looking, if you know what i mean... all powdery and white. This helps prevent the light from being "focused" in one spot, and the light spreads better.

 

[TwoHobbies]

If you look across the led there is a crown on the top. All I do is dremel the top flat. That gets rid of the spotlight effect. I have some before and after pictures somewhere if you would like to see them.

In the mean time here are some pictures of the hood and tank.