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DIY LED lighting?

Hi guys, great thread.
I feel infected by LED virus, and for sure I will try it.

Americans are playing with LEDs from few years now and I have found some threads on Aquaticplancentral forum.

One guy tryed estimated LED requirements for plants:

mcjosh13 said:
Anecdotal evidence from the few people who have used LEDs for planted aquariums (like Corry Keeper) seems to be inline with the aforementioned Lumen value so a good starting off guideline should be:

1. Around 61 white LED lumens/gal w/40 degree optics should support good plant growth similar to 2.5-3 WPG rule

2. Around 80 white LED lumens/gal without optics should support similar growth to above if the tank is not too deep. Also if not using optics, LEDs with more narrow radiation patterns (like Crees) will offer significantly better performance then those with wider radiation patterns like Seoul's and Luxeon's.
Link to whole thread: http://www.aquaticplantcentral.com/foru ... ter-4.html

Other guy from APC forum did experiment almost 5 years ego, growing plants side by side for comparison of 7x1watt Luxeons vs 1x7watt PC (Azoo palm light).


Link to whole thread: http://www.aquaticplantcentral.com/foru ... stars.html
 
I think the first one is far too much work for a realistic DIY setup. I remember the first link from JamesC in this thread where the chap wired up 800 or so normal LEDs for this. That rules almost all of us out and I don't think it would be too succesful

The second one is quite interesting although it doesn't show much to me. I've bored and infuriated some for a long time saying I would rather have T8 linear than PC lighting. Much better spread, better colouration and better growth IMO from the linear.

Would've been interesting to see his comparison of LED versus T5HO linear instead. I think they are not that far apart to the eye but I can already see the LED wins hands down growth wise. Maybe this is due to his 'flicker' theory of the fluoro not actually being on 100% of the time.

I see you talk about the radiation patterns of different types of LED (Seoul, Luxeon K2 etc.) Its not actually the different LEDs that have different radiation patterns. It is the die shape and if you look on the Philips site (link below) and no doubt the other manufacturer's sites that all of their LEDs are available with different shape dies!! There is Lambertian which is like a hemisphere, Batwing which has a flat front and rounded corners then flat sides, and then side emitter which is like a diamond's head.

http://www.philipslumileds.com/technolo ... tterns.cfm

The lambertian will push light equally around the hemisphere, batwing will push most ofit's light out of the front and Side Emitter will push front and sides:

However with all of them you can then use a choice of collimaters and lenses to 'focus' the light as desired.

Good project for 5 years ago though. Way ahead of the rest I have seen. ;)

AC
 
Here's some photographs of the LEDs I've been playing with. These are two 1W Luxeons with Batwing lenses, using 25° optics. They are powered by a Recom RCD-24 (the black box on the right half of the breadboard). The datasheet for the RCD-24 shows similar ICs capable of driving 3W LEDs, but I can't find anywhere that sells them.

The left half of the breadboard is this circuit (scroll down) minus the output transistor. It's just a simple 555 timer circuit for testing the dimmer. I plan to use a proper digital PWM through time.

At close to 0% duty cycle, the output is almost at maximum (the current is shown on the supply). It should read 350ma, but the rudimentary 555 Timer circuit isn't capable of producing a 0% duty cycle.
LEDs%20-%2008.jpg


At nearly 100% duty cycle the LEDs are very dim.
LEDs%20-%2009.jpg


These are just the extremes. I'm fairly impressed by the Recom. I can see myself using them.

I've also been playing around with the VariLED 16 LED driver. It's okay, but the analogue dimmer doesn't do much. The LEDs dim to about 60%, and that's it.

EDIT: When I get some decent heatsink material, I'll post a better shot of the actual light from a good number of LEDs using the dimmer.

EDIT2: I had some nice Oscilloscope screen captures, but for some reason they aren't being displayed. Too bad.
 
The lenses and heatsinks arrived today.

Very impressed with the lenses. they just clip onto the LED 'pushfit' style and look to me like they magnify the light quite a lot.

I only bought 3 for the new mini unit so I am going to try them on 1 series in the main luminaire. If they don't shoot beams into the water then I may get 15 more for the main unit.

AC
 
SuperColey1 said:
The lenses and heatsinks arrived today.

Did you get them from Hong Kong? I've got some on the way, slightly held up by the Chinese New Year.

I'm not keen on the optics I have at the moment. Too much light spills through the white plastic, and they don't stay in place all that well.

I'm going to need an eye test soon, after staring at all these bright LEDs.
 
Yep the lenses are from the same supplier as the LEDs off ebay.

Tried to fit them in the main luminaire to see what they were like and......

.......can't fit them on because the screwheads I used stop the lense holder clipping in place. lol

However if they look good on the small tank without beams showing through the water then I may reverse my main luminaire's design. I mean that there sould then be an acrylic panel instead of transparent glass, the lense is then superglued on the inside above very slightly smaller holes in the acrylic.

Then the LEDs just clip into place.

I will take a few photos of the way I have attached them in the small luminaire and try the small luminaire over the big tank to see what it is like with and without lenses.

AC
 
SuperColey1 said:
I mean that there sould then be an acrylic panel instead of transparent glass, the lense is then superglued on the inside above very slightly smaller holes in the acrylic.

I was thinking along similar lines. I was going to cut holes in plastic trunking, or something similar, and seal the lenses, so the lens holder becomes a column inside the trunking for the star to sit on. The trunking lid could then be closed on top, with cutouts made for the heatsinks. It'll probably be fiddly, but it means the heatsinks will be on the outside, and the electrics should be protected from the water.

It might be a while before I get a chance to start the DIY side of things. I'm concentrating on the dimmer circuit for now. I need to find a decent, cost-effective USB interface capable of delivering PWM (Pulse Width Modulation). When I find that, I'll have to write a program for it. It will take a while, but I'll get there eventually.

EDIT: This stuff is good for attaching LEDs to heatsinks (without using screws).
 
scottturnbull said:
This stuff[/url] is good for attaching LEDs to heatsinks (without using screws).

That would mean spending money. lol

The reason for the screws was that the original design is a board which then means every is hanging from above, hence the screws hold everything up. Seeing how good these lenses are with the push fit idea means I can fix to the bottom panel rather than the top panel and therefore Gravity works in my favour then ;)

You will see how I have done it with things I already had in the next post which I will start as soon as I have finished this one ;)

AC
 
Onto the Nano luminaire now. All finished in a total of about 6 hours of which most of that was spent on making the luminaire (and then getting a little carried away decorating it :lol:)

So here is the unpainted, unfitted luminaire on top of the nursery Nano (which I made out of an old window last week :))
The base panel where thelights will be is 6mm clear acrylic and the sides are 2mm. Again was somethng I had lying around. An old leaflet holder that my Dad brought around with a load of scrap wood that I made my shed from ;)

luminaireplain.jpg


The lenses on the Stars:
lens1.jpg

lens2.jpg

lens3.jpg


Then a star fixed to heatsink. I have used thermal compound because I had some from when I removed my PC processor during a problem period. I then superglued over the edges of the star to stop it 'sliding'
heatsinked.jpg


The lenses glued and then siliconed into position inside the luminaire. I wanted to actually fit the lenses into the holes but this acrylic is quite hard to cut perfectly and therefore I decided to fit these above the holes. If I do the main luminaire like this I will use wood because it is much easier to do these sort of holes and then I can fit the lense flush with the surface within the hole.

you can see how carried away I got with the decoration now. lol. Aluminium car spray, then some decals from a bike, then gloss enamel spray to finish it (all of which I had lying around)
lenseseal.jpg


And the lenses viewed through the holes:
lenseholes.jpg


Testing it viewed from below:
tes1.jpg


And an idea of the brightness of 3 LEDs. The floor below is about 3ft from the LED. The water in the tank this is going on will be about 6 inches below!!!:
tes2.jpg


And the finished article ready for the tank test!!!
finished.jpg


I will do a comparitive test of the light with and without lenses later although it won't be exactly scientific as I will 1 series of the main luminaire at the same height as this little luminaire for the 'without lenses' test. Therefore different LEDs and slightly different spacing but will give an idea of the difference between using and not using lenses.

AC
 
I'm doing my water change at the mo and then will do it once the water settles a little. give me an hour or so. lol

AC
 
Because I won't have time tomorrow and my photoperiod is from 3pm to 12am!!! therefore I normally do it Saturday mornings. lol

I also take my time on water changes.

Uploading photos now. May be tomorrow you see them now :lol:

AC
 
This is with the 'lensed' mini luminaire. 3 LEDs
smallfull.jpg


A little bit closer
smallpart.jpg


this is with the unlensed main luminaire lowered so the LEDs are at the same distance from the water. Just the 3 LEDs in this position are being used for this photo so is a reasonable comparison:
largefull.jpg


So you can quite easily see that without lenses the light is spread much better, however with the lenses it pentrates much better as you can see from the substrate in the 2 photos. 1 problem I see is that with lenses the light's 'colour' seems to be altered to slightly yellow!!! Maybe a trick of the eye.

Also to remember that looking at the first photo that is an 18" tall tank. approx 14" from substrate to waterline. The mini luminaire will be on a tank that is 8" tall and approx 6" from substrate to waterline!!! This picture says to me it will be fine:
tinylight.jpg


My conclusions which may be different to others is that on a highlight tank with much more than the 15 LEDs I have on my main luminaire then lenses should be OK but with 15 like mine then the lenses narrow the beam too much!!! The spread that you get without the lenses is much better for my setup. Howeve on the smaller tank then there doesn't need to be so much spread and therefore the lenses seem to work fine. Will be interesting to see what the colouration is like once the tank is running!

Your conclusions may be different.

AC
 
Tremendous stuff SC !! I was thinking of trying a nano setup, having followed your work on the main luminaire.

On the nano, if you wanted to have the LED's timed separately to create 'natural' lighting patterns, do you think it would be better without the lenses ? I'm wondering whether the lensed LED's have too much of a spotlight effect for this ? Just a thought :D

Any chance of a 'shopping list' for the nano luminaire :?:

Great stuff :D

Tony
 
Great stuff Andy; love the decoration of it mate! Pimped up nicely! :lol:

Interesting about the light spread. On a larger lumiere I suppose you could have a mix of lensed and unlensed LEDs to have a mixture of light effects. My next tank will definitely be DIY LED now!!!! :D
 
From this diagram you can see the problem that I would have if I 'lensed' the main luminaire with it's current amount of LEDs. This is due to their spacing. Seeing as I want a natural sun movement effect then its quite important to get an even spread through the tank whereas with these lenses there would be visible brighter spots. Shouldn't be a problem on the Nano because they are so close together.
smallfullpoints.jpg


This could be remedied by having more LEDs to get them all closer together but then I have already seen that growth is higher already than with the fluoros and therefore that would defeat another of my objects which is to stay 'lowish' light. lol

These are 30º lenses and there are 45º ones plus then there are eliptical ones that are 140º. I can't see the point in getting 140º ones to solve the issue because I may as well leave them as they are without lenses which is 'apparently' 120º. lol

They could be used for effect I suppose ;)

Parts list is 3 x 3W LED White (not warm white)
1 x 3W driver (from linked seller)
3 x lense (from linked seller)
3 x heatsink (from linked seller)
1 x 12V power adaptor
Wire
Silicon
Superglue
Thermal Compound or thermal tape.

With this seller you can just send them a message asking for the parts you want and they will give you a pretty good quote. I asked for 3 lenses and 3 heatsinks and they quote me $6 inc shipping (£4 :))
http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... :IT&ih=023

I would however get 5 LEDs, then you can match the best 3 colourwise and also have 2 spares incase they are needed.

No idea on the natural effect with 3 LEDs. For my knowledge that would still require 3 plugs and 3 individual drivers but I am sure there are other simpler ways of doing it ;)

AC
 
Great work. You should go into manufacturing.

I know what you mean about the lenses on the original tank. That's why I'm growing carpeting plants with my TMCs. I've got no other choice.

45° lenses might be better on a larger tank where the LEDs are spaced apart; or as you've done, just use the emitter lens on its own.

You even made your own tank. That's impressive DIY skills.
 
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