Mixed Results of Bleaching under T8 Setup

[gonewild]

There is also a "green" color factor that the human brain manipulates. For example when you have not seen any thing green for a period of time and suddenly you see a bunch of green your brain has a pleasure response and you see the most brilliant green and you feel pleasure. Then the next day when you see the same green again it is just normal green. :rollhappy:

This is what photographers have to deal with in trying to capture reality using natural light. The example I gave above is not mine it is from a former friend, Galen Rowell, who was one of the best mountain photographers ever. he wrote about the color of light in one of his books "Mountain Light".

This does not have anything to do with what light color grows better plants but it does show that you should not rely on judging growth on the color of green.
(But there is an exception to that also)

 

[garysan]

I checked the reading by the window and under the T8 lights.
The reading is crazy high. Then, the app shoots up this prompt saying I have to put a diffuser. So, I did as it directs.
Now the reading is crazy low. Even when I place the phone screen right up against the light, it is barely 1,050 fc. At the plant level, it is from 890 (short plants) to 1,000 tall plants that are about 8-10 inches away from the light.
This cannot be right I thought, then the app says the reading is abnormal and I need to calibrate. It is cloudy so I cannot do it.
It says I have to do it outside when it is sunny.
It is supposed to be rainy for the next few days, so I guess I will have to wait till some time next week.

Did you use white sheet of paper as a diffuser as the app asks to do?
I wonder if it's not white sheet of paper but clear paper as is shown in its demo pages?
I wonder this because when the white paper (I used an envelope), the reading was too low.

You definitely have to use a diffuser in order to get accurate readings but I think envelope paper is going to be too thick - might also have some 'design' on the inside which will confuse things further. I used standard 80gsm or 90gsm copier paper on mine but to be honest, I never calibrated it once I'd made the diffuser as the light levels I was seeing were what I was expecting to see (at the window, under old lighting setup, new setup, etc).

I am planning on investing in a proper light meter though as they're not hugely expensive and I want things to be as accurate as they can be.

No one seems to mention this, so I'm not sure if the detail in the original posting was all read, but majority of the plants are fine.
Some are even greening up. Hence the topic name, mixed results.
I don't really see anything consistant, and this is crazy!

It's worth noting that different species/hybrids/clones are used to or require differing light intensities. This is why you might be experiencing different results amongst your plants.

If it was me, I'd kill tubes 2 & 4 for the time being and to compensate for the plants that are doing well under your lights, perhaps move just those ones up a few inches closer to the lights you still have on and see how things develop (or leave them where they are and see how they adjust).

Further to Lance's suggestion about switching some lights on first to acclimatise the plants to morning and then doing the reverse at night; I think it's a great common sense idea that I'm mildly annoyed I didn't have myself when I built my rack....

Much the same as you, I'm not sure how I can easily integrate this to make it work now but will give it some thought for sure.

 

[Justin]

4 bulbs per shelf is way too much. Use only 2.

 

[gego]

The first time i used LED lights, my vanda got burned on one spot of the leaf which was not the closest to the light. Consider the angle of the light with the surface of the leaf. Since the light is not moving, the intensity is directed to that spot continuosly. Maybe just move those plants or position them differently. Then they will get used to it later. Consider the heat too
from those bulbs. It helps if you can change the angle of the light like what was suggested here by turning on/off the tubes.
Artificial lights can be decieving, At 1500 fc, I was able to bloom two spikes in my vanda. It may not read high in a meter but it really looks bright.

Sent from my HTC One using Tapatalk

 

[Happypaphy7]

Definitely yes

I guess my question was incomplete. lol
Sure, they are different!

What I meant to ask should have been, "is there something different in artificial light that might bring out this results?"

I know the basic mechanism of how visible light works with respect to the perception of human eyes.

Regarding the green color, a few plants whose leaf color was bleached and those that have not been affect (yet) are accurate because I noticed this difference when I took them out of the light stand to water them.

 

[Happypaphy7]

You definitely have to use a diffuser in order to get accurate readings but I think envelope paper is going to be too thick - might also have some 'design' on the inside which will confuse things further. I used standard 80gsm or 90gsm copier paper on mine but to be honest, I never calibrated it once I'd made the diffuser as the light levels I was seeing were what I was expecting to see (at the window, under old lighting setup, new setup, etc).

I am planning on investing in a proper light meter though as they're not hugely expensive and I want things to be as accurate as they can be.



It's worth noting that different species/hybrids/clones are used to or require differing light intensities. This is why you might be experiencing different results amongst your plants.

If it was me, I'd kill tubes 2 & 4 for the time being and to compensate for the plants that are doing well under your lights, perhaps move just those ones up a few inches closer to the lights you still have on and see how things develop (or leave them where they are and see how they adjust).

Further to Lance's suggestion about switching some lights on first to acclimatise the plants to morning and then doing the reverse at night; I think it's a great common sense idea that I'm mildly annoyed I didn't have myself when I built my rack....

Much the same as you, I'm not sure how I can easily integrate this to make it work now but will give it some thought for sure.

I can't wait until sunday (supposed to be sunny then) so I could calibrate the light meter app and use it. Hopefully it will work properly then.

Thanks for the suggestions. I will give one more week and see if anything changes for the worse. Then start playing around.

Interesting thing is the kind of plants that are affected. There are no patterns. One maudiae (among almost 20!) for example, and one Ho Chi Minh is also paler while the other HCM is perfectly fine.
The light "indicator" plant is getting darker, not brighter.
Oh, well...again, I hope the light meter will work properly on sunday and then I will continue on watching the plants for any change.

I will most likely make a change as you suggest and Lance's idea of dimming the lights.

Thanks, all!

 

[Happypaphy7]

4 bulbs per shelf is way too much. Use only 2.

Alright.

 

[Happypaphy7]

The first time i used LED lights, my vanda got burned on one spot of the leaf which was not the closest to the light. Consider the angle of the light with the surface of the leaf. Since the light is not moving, the intensity is directed to that spot continuosly. Maybe just move those plants or position them differently. Then they will get used to it later. Consider the heat too
from those bulbs. It helps if you can change the angle of the light like what was suggested here by turning on/off the tubes.
Artificial lights can be decieving, At 1500 fc, I was able to bloom two spikes in my vanda. It may not read high in a meter but it really looks bright.

Sent from my HTC One using Tapatalk

Great point!
Moving light vs. in-place light hitting on the plants for 12 hours straight in same intensity!

Heat is something I was initially concerned about.
After visiting people with T5 HO, the heat was just amazingly high.
While heat my T8s are giving off are not that bad, but I can definitely feel it when I just walk by the stand.

I guess I'll put a small fan on or something.
I don't like to use any fan unless I am hot in the summer time. lol

Somehow, I always had this idea that T8 is not as strong as T5.
Can't imagine how terrible results might have been had I started out with T5. Yikes!

 

[gonewild]

I guess my question was incomplete. lol
Sure, they are different!

What I meant to ask should have been, "is there something different in artificial light that might bring out this results?"

The answer is still...yes.
Besides the color spectrum of artificial light which will cause the leaves to react differently and grow differently depending on which color tube you use they are also different from natural light.

Artificial light is very constant in intensity where sunlight fluctuates all day long and as discussed earlier the suns light intensity is in constant change from sunrise to sunset. It may be that constant non fluctuating light has a different overall effect from fluctuating natural light. Maybe the plants don't really like to function at a constant maximum output provided from artificial light??

When one plant in a group gets bleached out and the others look perfect then most likely genetics may be the cause. Each plant has it's own individual tolerance to stress and will react differently from it's siblings. Just because they are all the same species or hybrid does not mean they all have exactly the same behavior.

Of course this all assumes that the bleached plants are healthy and have equal roots to to others.