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This could also be from diffraction and mixing: as light hits a solid edge, it spreads out. It's the same pricipal as a pinhole camera, and might be mixing the reds and blues more.Quote:
Looking at my quick duct tape fix, it does seem to be growing best just under the edge, but not too far.
I managed to get (8) XPEBLU-L1-B40-K3-0-01 Blue 470-480nm 35.2 Lumen @350mA (cree xp-e)
placed on my order of (8) cree xp-g's before they shipped for $48.72 additional. Thats a $116.42 total
At least I didn't pay shipping twice.
I have a feeling these and the ledengin 660nm and the 680nm leds will make quite a setup. Those are going to be
about $220 plus around a $100 more for drivers etc...
Hope this helps anyone thinking about getting leds. Don't
At least when they become more affordable I will know what to get, what works, and how to use them.
I hope I am doing this right. Time will tell.
Side note where the xp-g drops off the most is where the new blue fills the gap i.e. 470-480nm.
Another improvement I have been throwing around is that the royal blue rebels are, as far as I've found yet, some
of the lowest (nm) and affordable readily available leds. The peaks of the rebel royal blue (447nm), the cree, the bin I bought, is (475) and
the cyan rebel peak is (505). So the combination/mixture between the three seems to me to cover a great part of the spectrum
needed for the low nm needs for the chlorophyll and good amount of the the cartonoids.
As always I am thinking aloud so that anyone could give me an opinion and/or corrections on my thoughts.
One problem I am seeing is that with so many blue leds, even at low 350 mA, I will need more reds.
Or another way of saying it more money and diffusion has always been something I have been struggling with.
Thanks for any help.
Well, not exactly. Diffraction is only pronounced when the slot size is on the order of the wavelength.Quote:
Originally Posted by SantaMonica
But under the tape, it is purely reflected light, not direct. And it is reflected from the white paint, which scatters very well,
so yes, it is more mixed.
However, the red/blue/red LEDs are only a few inches apart, and about 6 inches up, plus I have a layer of diamond diffusion lighting grid,
plus, the growth on the screen is quite uniform.
So all evidence is that it really has to be mostly about intensity, not mixing.
Although there is a chance that the wavelengths do not reflect the same. Blue tends to scatter quite a bit more. (Blue sky)
Maybe, but since algae seems to grow just fine in reef display tanks, which have a TON of blue and almost no red, I wouldQuote:
Originally Posted by inkidu
not worry. And in fact, it might be a good thing.
Although you may end up with some Coraline algae growth. ;)
I'll take a picture of the bottom of my scrubber tub(large walmart tote) its totally covered.
Regarding Inkidu's cost concerns.
I just put down $150 just for T5 bulbs for my main tank. And it is already 1/2 LED as well.
A decent actinic is $25, and only lasts about 6 months. (Maybe over driving was a mistake)
But yeah, sure seems that you like to spend money. 8-)
Please don't remind me (cost) it is easier if I don't think about it. Cool picture.
Just now filling in the paper work to get the 680 nm leds.
I used a spectrometer to calculate/estimate the spectrum of ledengin deep red. Just curious.
Using a hydrogen lamp as a reference the deep red had a spectrum that was very defined on one side,
the side slightly higher than the hydrogen red spectra llne (656), and then gradually tapered toward the yellow end of the spectrum.
Which does match the spec in that the slope of the line seemed to taper off more gradually on the yellow side than the red.
Seems that most curves are balanced on each side.????
I also notice that the total/whole spectrum was much tighter for the warm white led in comparison to an incandescent bulb.
Still researching why. Just thinking now if there would be a way to place a piece of paper by the eye piece and take a picture of the spectrum.???
Might be to dim and the light to bright.
Hope this helps.
You think white LED spectrum is tight? the color ones are very tight. both pro and a con depending on what your after.
If anyone is interested. This seems like a good deal, free shipping now >$100 till end of April, and the right parts.
From cutter a bin labeled 2700K very warm white (i have never seen a high power bin 2700K led before)
http://www.cutter.com.au/
XPEWHT-L1-8B-P4-0-01 Very Warm White
Also think that this blue works well because it replaces the nm where the warm white falls off i.e. 470-480
- XPEBLU-L1-B40-K3-0-01 Blue 470-480nm 35.2 Lumen @350mA
The cree XP-E does have a smaller die than the XP-G but if you wanted to disperse the light you might want to have
something less powerful anyways.
The # I get when you figure in free shipping is $114.80
That would be for (10) XP-E warm whites and (10) XP-E blues
Just a suggestion if anyone wants to try. Shipping is usually $12
I don't have any affiliation with the company. What makes them different is that you know the exact bin/color that you are getting
and those bins are the latest ones. Most company's don't give the exact bin #'s, unless you buy a 1000 pieces. The bin # can be important.
I personally am adding ledengin (660) deep reds and (680)
http://www.tech-led.com/data/SMB680-1100-I.pdf
to a similar XP-G and XP-E mix.
Just a suggestion if anyone wants to try led.
Hope this helps.
That does seem like a good deal. And knowing the bin makes a big difference.
Any problems getting things from Australia?
I have been reluctant to use them.
On other news:
1) REV-3 LED system is up and running.
I added 3 warm whites, and spread LEDs out to now cover the whole ATS. Old half-CFL is gone.
So far, looking good.
2) I seeded the screen.
Rode my bike out to the bay, grabbed some algae, and scraped it on my screen.
Not much stuck to the screen, but the few little strands that did have EXPLODED in growth.
The rest is still growing weakly as before.
So that might be the trick! I will do some serious re-seeding this weekend.
Need more time for detailed posts and results.