Lux levels and neps

[manders]

Bought a cheap lux meter off ebay and been measuring few things, just wondered if anybody else has measured the light levels with the neps, especially those under electric lights? For example my amps are getting about 4000 lux of an envirolite. Those under T8's are getting about 1000 lux.

Edited October 9, 2010 by manders

[gabew]

very interesting

i have tried to do a similar thing with the lights(see here) on my 2 tanks

the seller (claim) they lights put out 15,000 lumens, so by my math 15,000 lumens over .8 sq meters (the growing space of both tanks) equals about 18,750 lux

now these lights have these 2 kind of odd double 2 foot T5 lights, so to put them into prospective with normal T5 lights the same seller claims that their 4 foot 6 bulb lights (see here ) put out 30,000 lumens, so if you divide that be 2, because these lights are twice as long as mine, you come out with the same 15,000 lumens, therefore as far as i can tell my lights equivalent to 6 2 foot T5s

those are my calculations, if the sellers are exaggerating and those numbers are way to high or if i did my math wrong please tell me, but i am really pleased with these lights overall they are REALLY bright!

oh looks like i did my math wrong and the lights put out more than i thought , turns out they get a lot more light then i thought, even better! thanks manders

Edited October 11, 2010 by gabew

[Zhilin]

Bought a cheap lux meter off ebay and been measuring few things, just wondered if anybody else has measured the light levels with the neps, especially those under electric lights? For example my amps are getting about 4000 lux of an envirolite. Those under T8's are getting about 1000 lux.

amps do not require high light. But your light probably is weak for most neps. At least, the lux needs above 10,000 lux (put the meter near the neps and the meter should give the measurement). My Heli, Cep are growing under artificial light with 20,000 - 30,000 lux, and they grow fast. But try your best to provide more lights. Most my HL neps are growing with 3 hours of direct sunlight which provides around 100,000 lux, and with 5 hours of filtered sunlight which provides about 10,000 - 30,000 lux.

[Phil Green]

Mark - what Watts are those lights ?

I might have to get a meter my self and check mine.

Out of interest, does having the walls overed in mylar to reflect the light increase the lux the plants get, over just the lights without mylar ??

[marcello catalano]

if you like, I found two very interesting links (the first one is basic but essential, the second one is more complicated but still...):

http://www.littlegreenhouse.com/guide3.shtml

http://www.waynesthisandthat.com/fluorescent.html (from a guy who started being interested in this because of a Dionaea)

[manders]

Mark - what Watts are those lights ?

I might have to get a meter my self and check mine.

Out of interest, does having the walls overed in mylar to reflect the light increase the lux the plants get, over just the lights without mylar ??

Phil, the envirolites are 200 & 250W, the T8's were 2x2ft 18W tubes. With the amps I haven't tried Mylar, I just have the three walls painted white. I measured the light about 1ft under the envirolites and about 7 inches under the T8's

[Mags]

Bought a cheap lux meter off ebay and been measuring few things, just wondered if anybody else has measured the light levels with the neps, especially those under electric lights? For example my amps are getting about 4000 lux of an envirolite. Those under T8's are getting about 1000 lux.

Ive been thinking about getting one too, ive always been curious about the amount of light windowsill neps receive compared to those grown under lights...

[Phil Green]

Thanks for the link Cello.

I see it says T5 are more efficient than T12 and I was going to ask if T8 tubes which I use are about in the middle - BUT I've just discovered that things have changed.

The tubes I was buying seem to have recently been discontinued and replaced. It seems they were halophosphur tubes, which have now been replaced with Triphosphur tubes and the info says "A new generation of triphosphor coated fluorescent tubes.

Using T8 triphosphor tubes in place of T12 and T8 halophosphor tubes, increases light levels and extends lamp life, up to 20000 hours when used with electronic control gear, improves colour rendering performance and reduces maintenance and energy costs."

It say's they have a 5-10% increased luminaire efficiency.

The technical data for a 3ft tube (30W) (I use 2ft and 4ft tubes) says 'output(lm) 3250. looking at the light chart for daylight tubes it has peaks at about 440, 550 with a main peak about 610 and a smaller peak about 410.

http://www.tlc-direct.co.uk/Main_Index/Lig...phor/index.html

So, does anyone know anything about this new technology and how these T8's will compare to T5 ?

[manders]

very interesting

i have tried to do a similar thing with the lights(see here) on my 2 tanks

the seller (claim) they lights put out 10,000 lumens, so by my math 10,000 lumens over .8 sq meters (the growing space of both tanks) equals about 8,000 lux

now these lights have these 2 kind of odd double 2 foot T5 lights, so to put them into prospective with normal T5 lights the same seller claims that their 4 foot 6 bulb lights (see here ) put out 30,000 lumens, so if you divide that be 2, because these lights are twice as long as mine, you come out with the same 15,000 lumens, therefore as far as i can tell my lights equivalent to 6 2 foot T5s

those are my calculations, if the sellers are exaggerating and those numbers are way to high or if i did my math wrong please tell me, but i am really pleased with these lights overall they are REALLY bright!

They sound like a pretty decent option for a grow light, about 90 lumens per watt, you maths is a bit wonky though it should be 12,500 lux.

[manders]

amps do not require high light. But your light probably is weak for most neps. At least, the lux needs above 10,000 lux (put the meter near the neps and the meter should give the measurement). My Heli, Cep are growing under artificial light with 20,000 - 30,000 lux, and they grow fast. But try your best to provide more lights. Most my HL neps are growing with 3 hours of direct sunlight which provides around 100,000 lux, and with 5 hours of filtered sunlight which provides about 10,000 - 30,000 lux.

I believe your wrong, they might like 10,000+ lux but they certainly don't need it to grow. I guess you got the figures of a well know website . Also if i had to light all my neps to 30000 lux I'd need a small nuclear power plant in the back garden, luckily I have very few under lights.

[Dicon]

Hi Phil,

I remember reading an article in an Orchid journal I think and the guy had done extensive tests with tubes and one thing I do remember was that he found T8,s were the most efficient diameter wise.

I'll try to find the article.

[Phil Green]

one thing I do remember was that he found T8,s were the most efficient diameter wise.

Phew - thats lucky for me (pure luck on my part). So I guess with these new tubes being even more efficient, that makes them even better I do need more as I'm just about to put my last two tubes into a new light going up and then I won't have any spare. I almost wish I didn't get a load of 2ft tubes now (they were cheaper the more you bought), as it will be a few years before I need more of them.

[dchasselblad74]

I've used both metal halide and t5s for my reef tank(5 year old reef 150 gallon), and t5s lose spectrum every 6 months...And this is known in the Marine Hobby community...I can tell when the t5 bulbs need replacing, cause my live coral lose their color a little bit, plus the t8s doesn't project heat, which is bad for the ambient temp of the marine water, which needs to stay at constant 77 F . So overall the t8 lighting is also very promising in the marine aquarium hobby.

DexFC

Edited October 10, 2010 by dchasselblad74

[Zhilin]

I don't think I am wrong. These figures not come from any website, just come from my Mastech Professional Luxmeter (LX1010B). And I just measured the light in my tank for my helis, and the light was around 30,000 lux. I used a Feit Electric ESL40TN/D 42-Watt Compact Fluorescent High-Wattage Bulb (with reflector on the tank back) to achieve this. So, you definitely do not need a nuclear power plant :)

In my view, 10,000 lux is not enough for many HL neps. Under this light, most HL neps lost their beautiful color. In orchid world, 8000 - 10,000 lux (equivalent to about 800-1000 footcandle) is the light only for those low-light orchids. For those high-light orchids, the light needs to be 30,000-40,000 lux. Neps have similar light requirement. And 30,000-40,000 lux is the light intensity measured in most greenhouse for CPs.

I believe your wrong, they might like 10,000+ lux but they certainly don't need it to grow. I guess you got the figures of a well know website . Also if i had to light all my neps to 30000 lux I'd need a small nuclear power plant in the back garden, luckily I have very few under lights.

Edited October 11, 2010 by Zhilin

[johns]

I don't think I am wrong. These figures not come from any website, just come from my Mastech Professional Luxmeter (LX1010B). And I just measured the light in my tank for my helis, and the light was around 30,000 lux. I used a Feit Electric ESL40TN/D 42-Watt Compact Fluorescent High-Wattage Bulb (with reflector on the tank back) to achieve this. So, you definitely do not need a nuclear power plant :)

At what distance from the light source did you measure?

[Dicon]

In orchid world, 8000 - 10,000 lux (equivalent to about 800-1000 footcandle) is the light only for those low-light orchids. For those high-light orchids, the light needs to be 30,000-40,000 lux. Neps have similar light requirement. And 30,000-40,000 lux is the light intensity measured in most greenhouse for CPs.

I don't really agree, most Neps grow in forested areas, where they thrive in shadier conditions, their vines may climb into better light but most rosettes are in thick vegetation or moss.

There are always exceptions but many lowlanders in particular mainly grow in deep shade.

You have to consider the shade provided by other vegetation, many epiphytic orchids for example grow only on the "dark side" of their chosen tree.

I don't think it is safe to generalize with Nep species.

[manders]

I don't think I am wrong. These figures not come from any website, just come from my Mastech Professional Luxmeter (LX1010B). And I just measured the light in my tank for my helis, and the light was around 30,000 lux. I used a Feit Electric ESL40TN/D 42-Watt Compact Fluorescent High-Wattage Bulb (with reflector on the tank back) to achieve this. So, you definitely do not need a nuclear power plant :)

In my view, 10,000 lux is not enough for many HL neps. Under this light, most HL neps lost their beautiful color. In orchid world, 8000 - 10,000 lux (equivalent to about 800-1000 footcandle) is the light only for those low-light orchids. For those high-light orchids, the light needs to be 30,000-40,000 lux. Neps have similar light requirement. And 30,000-40,000 lux is the light intensity measured in most greenhouse for CPs.

The only way you can get 30,000 Lux of a 42w bulb is if your growing area is about 0.1m2. Translated into a decent sized growing area that amounts to about 5kW of power and some hefty additional power for cooling. The power bill would be at least 6k$ per year. Not quite a nuclear plant but definitely more than I would like to spend on lighting.

Also you have to consider that some of my plants are 10-12ft high, providing the whole plant with 30,000 lux is not possible.

I agree many neps enjoy a bit of sunshine, but i've had many plants color up quite nicely under very low lighting, e.g. all red mirabilis under 40W of fluorescent with about 1000 Lux. And many seeds raised under similar conditions, so higher levels may be nice, but certainly not necessary.

Thats what was interesting about actually measuring the LUX levels to see they are actually responding under different conditions.

Last night I got around to measuring the levels under a 400W dual color sodium light, with a bit of better positioning I think I can light most of my conservatory to about 2000Lux which is more than enough to get them through the winter and keep em growing at a decent rate.

Edit:

For comparison, you can only get 30,000 Lux <3 inches away from a 250W envirolite (CFL).

Edited October 11, 2010 by manders

[Zhilin]

Well, I agree if one wants to grow large sized neps under artificial light, 30,000 lux is not possible because of the power bill. But you really refresh my knowledge about the light requirement of neps. I never know that 1000 lux is enough for neps. Even in bright shade, the light intensity is about 10,000 lux, and I was told that never keep neps in bright shade for ever. But my neps are mostly HL. I know, for LL, the light requirement can be reduced much.

Anyway, my point is, if one can let his/her neps get sunlight, then do it. High light can encourage pitcher forming, color up pitchers, fasten growth, and make neps robust to disease.

All my neps are growing outdoor receiving direct sunlight for several hourse. I only grow two helis and a nep seedling under the artificial light. With a small tank, reflectors on the tank walls, and the bulb put 4 inch away, I can easily achieve the intensity from 15,000 lux - 28,000 lux depending on locations of the tank.

The only way you can get 30,000 Lux of a 42w bulb is if your growing area is about 0.1m2. Translated into a decent sized growing area that amounts to about 5kW of power and some hefty additional power for cooling. The power bill would be at least 6k$ per year. Not quite a nuclear plant but definitely more than I would like to spend on lighting.

Also you have to consider that some of my plants are 10-12ft high, providing the whole plant with 30,000 lux is not possible.

I agree many neps enjoy a bit of sunshine, but i've had many plants color up quite nicely under very low lighting, e.g. all red mirabilis under 40W of fluorescent with about 1000 Lux. And many seeds raised under similar conditions, so higher levels may be nice, but certainly not necessary.

Thats what was interesting about actually measuring the LUX levels to see they are actually responding under different conditions.

Last night I got around to measuring the levels under a 400W dual color sodium light, with a bit of better positioning I think I can light most of my conservatory to about 2000Lux which is more than enough to get them through the winter and keep em growing at a decent rate.

Edit:

For comparison, you can only get 30,000 Lux <3 inches away from a 250W envirolite (CFL).

Edited October 12, 2010 by Zhilin

[manders]

Well, I agree if one wants to grow large sized neps under artificial light, 30,000 lux is not possible because of the power bill. But you really refresh my knowledge about the light requirement of neps. I never know that 1000 lux is enough for neps. Even in bright shade, the light intensity is about 10,000 lux, and I was told that never keep neps in bright shade for ever. But my neps are mostly HL. I know, for LL, the light requirement can be reduced much.

Anyway, my point is, if one can let his/her neps get sunlight, then do it. High light can encourage pitcher forming, color up pitchers, fasten growth, and make neps robust to disease.

All my neps are growing outdoor receiving direct sunlight for several hourse. I only grow two helis and a nep seedling under the artificial light. With a small tank, reflectors on the tank walls, and the bulb put 4 inch away, I can easily achieve the intensity from 15,000 lux - 28,000 lux depending on locations of the tank.

Zhilin,

I'm not disagreeing with you, the more light the better. But even with a 250w light, the best you can get for a small nepenthes is around 4000 lux, unless you are growing a baby plant inside a jam jar, and you can place most of the plant a few inches from the light source, not realistic for anything approaching an adult flowering size plant.

I also agree 1000 lux seems to be around the lower end of the range for growth, good colour needs more light, or possibly uv. Not sure I would distinguish low and highlanders in the same way, never noticed any difference with regards to light.

[manders]

Thanks for the link Cello.

I see it says T5 are more efficient than T12 and I was going to ask if T8 tubes which I use are about in the middle - BUT I've just discovered that things have changed.

The tubes I was buying seem to have recently been discontinued and replaced. It seems they were halophosphur tubes, which have now been replaced with Triphosphur tubes and the info says "A new generation of triphosphor coated fluorescent tubes.

Using T8 triphosphor tubes in place of T12 and T8 halophosphor tubes, increases light levels and extends lamp life, up to 20000 hours when used with electronic control gear, improves colour rendering performance and reduces maintenance and energy costs."

It say's they have a 5-10% increased luminaire efficiency.

The technical data for a 3ft tube (30W) (I use 2ft and 4ft tubes) says 'output(lm) 3250. looking at the light chart for daylight tubes it has peaks at about 440, 550 with a main peak about 610 and a smaller peak about 410.

http://www.tlc-direct.co.uk/Main_Index/Lig...phor/index.html

So, does anyone know anything about this new technology and how these T8's will compare to T5 ?

I also wondered if anybody has tried these?

http://cgi.ebay.co.uk/2ft-LED-Tube-T8-in-S...e#ht_2270wt_785

[Phil Green]

That's freaky - never seen anything like that before