anyone use LED lights

[Mikey8567]

There are UV LED's 250-385NM and others too. the big thing is that most LEDs are a focused light not like a cfl or t5 bulb that projects light in all directions. They are more like a spot light then a flood light. You can get varied angles of light based on the type of LED you get. You'll notice it's rated at viewing angle. Every day newer leds are hitting the market covering more of the light spectrum and brighter also. Big thing is if you build a UV LED light source you need to do two things. #1 have a base UV rating of a standard CFL/t5 bulb as a reference. #2 Build up with the # of LEDS you are using. In other words start it with a few leds and take a reading, then add LED's as need to approach the desired UV rating but never exceeding it. You could easily blind your pet or even yourself if your not careful. As for the LED drivers or even simply the right size resistor to put in-line with the led based on the power source, you can google it and there is many DIY sites based around LED's and such.
Hope this helps.

[pgaks2]

it seems if your DIY enough and electronicly gifted( i am not but might have to tap into some knowledge from some friends) that you could build a single board or series of boards to support night, sunrise, daylight, sunset. this is my dream at least but like i said, on the electrical side of things i suck.

sheb

[beckdg]

night lights can kill plants... i'm sure some of you remember when i put green led's over my fish tanks... very dim... yet nothing grew underneath them... just an fyi.

[froggsong]

Really beck? That's interesting. Do you think it was the color, or was it that it was light at all? I was running one of those marine glow bulbs at night on our 29G aquarium, and some of the plants weren't doing too well. I know they also need ferts, but since changing out the light for a regular bulb and only running it 14hrs or so, the plants are doing alot better.

I've used red lights at night in my terraria with no adverse plant reactions. I've also used black lights (the incandescent type you get from wally-world, they have them super cheap around Halloween, but I forgot to get some this year) with no issues, other than burning the leaf tips that were directly under the bulb, I'm sure that was because of the heat and not the light, though. Those suckers get HOT!

I wasn't aware that they were making UV LEDs. That's quite good, actually. They could be much cheaper in a few years than the tubes we are using now. I wonder if the UV degrades over time in them like it does in the tubes? If not, it would make even an expensive purchase worthwhile, since you wouldn't have to replace them constantly. Which reminds me, it's about that time again... ugggghhhh.

It would be interesting to see if the guys at UV guide UK would test some of the UV LEDs and post their findings. Their research is quite good, and has helped me greatly in the past when choosing a UV source.

[beckdg]

honestly, i think it was light period. i lost some very easy plants to care for. aponogeton and crypt wendti green as well as java moss and something else i can't seem to remember. keep in mind the pics i posted had a huge delay in shutter speed. i'd say somewhere between 30 seconds and 1 minute. that's why it looked so bright. mind you to see anything in there with the nightlights on the entire house had to be black and i really still couldn't see the bottom.

anyway the one thing that i noticed is at the very top the light did shine green. as the light penetrated further down the color washed out to blue... almost white. so i'm thinking the water cancelled out the green and that might've been my problem.

regardless, what tipped me off that it was the night lights was location. everything directly under them was dying. java ferns would not spread there, apon leafs would melt once they grew under it, java moss kinda burned over night in that area, etc..

i keep my setup very low light for low maintenance so some plants are still bouncing back now.

also i doubt intensity had anything to do with it. all the night light setups i've seen have at least 3 led's in each lamp head. mine had only 1 per lamp. granted it was 4 lamps (4 led's total) that still does not account for the difference of 3 sets of 3 compared to just 4 singles.

[Mikey8567]

I'm looking into doing some tests with the UV for a few reasons. #1 Working on some paintball hoppers that would use glow in the dark paint and it uses UV LEDs to charge the paintballs. #2 I am curious about he apps involving the tanks and such. Just got my Digi-Key catalog (damn things 2700 pages of stuff) and I am checking out the LED sections. I've done tons of LED projects for hight lighting of Cam's (IR LED's) and many apps involving interior and exterior lighting. I'll try and keep you all up to date on what I find and how it's going. One benefit is that the LEDS can be dimmed, so that means the UV output value could be controlled.

[Mikey8567]

Originally Posted by beckdg

also i doubt intensity had anything to do with it. all the night light setups i've seen have at least 3 led's in each lamp head. mine had only 1 per lamp. granted it was 4 lamps (4 led's total) that still does not account for the difference of 3 sets of 3 compared to just 4 singles.

Well LED's are rated like light bulbs, in the referance of their output in MFD ect. So as to say I could get 1 LED that puts out the same if not more then 3 LEDs. The thing with LEDS you have concider is a few things, #1 The MFD (brightness), #2 The viewing angle in degrees, #3 Their Max operating forward voltage (They are diodes), if you run one at 1/2 it's rated FV it will only put out 1/2 the MFD but will last longer, on the other hand running it at full FV or near it, it will put out the rated MFD but shorten the life of the LEDs. Most Mfgr's run the LED's at or around 3/4 of their FV to make the LED last long and still put out alot of light.

Opps got all techy again.

[froggsong]

lol, techy is fine. What does MFD stand for? I know that LED is light emitting diode, but I'm curious what the other one stands for.

[beckdg]

thanks mikey.

they were nothing special though. they were night lights from walmart that i painted myself. they were your normal run of the mill 1 watt max led bulbs. anything running 9 bulbs is definitely putting out 2.25X what i was running or more. not only that but there were light sensing dimmers on the housing that lowered that output according to ambient light. considering they were placed above an all glass top i'm sure even their own re strike was enough for the sensor to lower the total wattage output on each bulb.

as far as i know running an led/diode at 1/2 power puts out closer to 3/8 light output and closer to triples the life span than doubles. you are correct as with most other electronics lowering the power consumption and radiant heat lengthens the life and sometimes efficiency.

i was wiring up led's since sixth grade wood shop so i can handle it. i might not remember all the technical terms from electronics engineering classes 14 yrs ago since it wasn't something i wound up pursuing but the work itself is not that hard.

not only that but if you notice the list of plants i gave you'll see that many of them could almost survive in a dark closet for some time. this tells me that it takes very little light for them to be photosynthetically active. not giving a break at night time is pretty much what was doing them in... not how intense the light was. i am 100% sure of that.

oops, got all multi-platform technically anal again. lol

trust me mikey, they were nothing like what you'd see in the break lights of a new caddy... or a stop light... my tank is about 21" high with 4" of gravel and they didn't reach the 17" it took to get to the bottom.

[beckdg]

probably refers to microfarad.