Pretty pleased with a purchase I made . . .

Picked up a pair of these:

[www.ledwholesalers.com]

Going rate about $25 in their eBay store . . . 13 watts each, so far so good.

My little growing station:

great idea. Will make it harder for the DEA to pinpoint you.

The general rule of thumb with artificial light, is that for every inch a light source is away from a plant, it must be on for that many hours to provide the light that the sun would provide in a normal day.

For example: If your light source is 19 inches away from your plants, your lights must be on for 19 hours a day.

Ok this may be a dumb question - it says they ARE full spectrum lights - would they emit UV-A or UV-B? If so, these could be really good for reptiles.

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freeradical
The general rule of thumb with artificial light, is that for every inch a light source is away from a plant, it must be on for that many hours to provide the light that the sun would provide in a normal day.

For example: If your light source is 19 inches away from your plants, your lights must be on for 19 hours a day.

Wouldn't that depend a lot on the particular light?

This one may be radiocative judging by the description:
"it will make your rocks glow!"

[www.ledwholesalers.com]

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Black

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freeradical
The general rule of thumb with artificial light, is that for every inch a light source is away from a plant, it must be on for that many hours to provide the light that the sun would provide in a normal day.

For example: If your light source is 19 inches away from your plants, your lights must be on for 19 hours a day.

Wouldn't that depend a lot on the particular light?

Sure, perhaps a little bit if you have a highly efficient light source. It's possible that some source might only need to be on for 18 hours a day if it's 19 inches away. There is nothing like the sun. Another problem with artificial light sources is that they have to be pointed at all parts of a plant, not just the top. A lot of people use artificial light sources for plants such as african violets because they are short and compact, so you can get away with just downward pointing lights.

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Black
This one may be radiocative judging by the description:
"it will make your rocks glow!"

[www.ledwholesalers.com]

Nah, it's just doing what the energy source for a laser does; it's exciting electrons into higher orbits, which then fall back down and release energy in the form of light.

The inch/hours thing maybe a rule of thumb but it's bogus. And it's easy to disprove; move a light from 6 to 12 inches and its brightness is reduced by 3/4, not 1/2. You'd need to quadruple the photoperiod, not double it.

You can figure out footcandles from the lumens of the light source, but even then it would be a rough estimate because every grow light has a wonky spectrum. If you want to mimic sunlight's approximate 10,000 foot candles, you'd first have to know the bulb's intensity at 430 and 680 nm.

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Stephanie
would they emit UV-A or UV-B? If so, these could be really good for reptiles.

No. They're not full spectrum, not even close. They emit light at 465 and 650 nm, and only at those wavelengths. Reptiles need UVB light somewhere around 300nm.

Not sure how you can be pleased without any results yet.

Also there is no substitute for the sun.

A bit late to start seedlings. I started mine 6 weeks ago.

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Wild eep
Not sure how you can be pleased without any results yet.

Also there is no substitute for the sun.

A bit late to start seedlings. I started mine 6 weeks ago.

I'm pleased with the quality of the lights for the price I paid.
I do not have sun inside my apartment.
I'm starting these at exactly the time I want to.

I started this thread just for you, Penelope. I can go to bed now.





Edited 1 time(s). Last edit at 04/18/2009 07:04AM by Black.

stops the seedlings from growing tall thin and spindly.
some plants (like marigolds ) are less likely to reach for the light
[www.napervillecommunitygardeners.org]

the lights adjust up as the plants grow taller.

interesting lights, though.
even many flourescent tubes on 14 to 16 hours a day can run an electric bill up

I forgot how I got to this site, but it has an LED array that puts out about as many lumens as a 400 W halogen.
[tesladownunder.com]

---

In tha 360. MRF User Map

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Mike Johnson
No. They're not full spectrum, not even close. They emit light at 465 and 650 nm, and only at those wavelengths. Reptiles need UVB light somewhere around 300nm.

Thanks. That's kinda what I figured. I don't have a need for UV lights (only keep snakes) but I know several people with lizards.

So when can we all come over for brownies?

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Mactel
So when can we all come over for brownies?

Sorry to dissapoint, the best I can do is some poppies that are sprouting like mad.
Don't know anything about how to process them though.

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Stephanie

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Mike Johnson
No. They're not full spectrum, not even close. They emit light at 465 and 650 nm, and only at those wavelengths. Reptiles need UVB light somewhere around 300nm.

Thanks. That's kinda what I figured. I don't have a need for UV lights (only keep snakes) but I know several people with lizards.

They come in various LED combinations-- dig around the site.

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billb
stops the seedlings from growing tall thin and spindly.
some plants (like marigolds ) are less likely to reach for the light
[www.napervillecommunitygardeners.org]

the lights adjust up as the plants grow taller.

interesting lights, though.
even many flourescent tubes on 14 to 16 hours a day can run an electric bill up

When I set it all up I didn't feel like digging beyond what I had immediately available (hence the zip ties and cup hooks) but I had planned to lower the lights once I started getting sprouting-- need to dig around and find some mini-bungees.

I had had a 48" flourescent hood suspended from that same spot over a 65 gal. Aquarium originally, but apart from the enegry useage the hoods are unsightly and attract dirt, apart from being frustratingly flimsy (unless you spend way more money than I would be inclined to . . .)



Edited 1 time(s). Last edit at 04/18/2009 12:31PM by Black.