LFS_worker
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An excerpt from one of the references that you have cited :


Indoors, light levels are very poor. Though imperceptible to the human eye, light levels drop rapidly the further you are from a natural source of light. It is said that light levels halve every 50cm further from a window you are. This means that for most tree species light levels are too low, even when stood on a bright window-sill. It needs to be understood that glass filters out many of the UV rays that plants require for the process of photosynthesis; many trees species can fail to receive enough light on a south-facing window-sill even though the heat of the sunlight is burning their leaves.


This is absolutely incorrect Through studies of light and UV filtering glass in the saltwater hobby it is KNOWN that this information is wrong.

In plain daylight there is about 100,000 lumens of light this is with no cloud cover in late may in upstate New York.

The exact same sunlight at same time of year behind Low E tripple pane argon filled glass is about 45,000 lumens, and at 5 ' from the windpw there is about 44,000. These windows are one of the most energy efficient windows on the market as of current. There is more than ample light to encourage photosynthesis at these lumen levels.

For the record these are not P.A.R. levels or P.U.R. levels and please do not be confused if you are looking for P.A.R. levels I can do that into the future but for argument sake the article is wrong.

If you want your tropicals and others to do well indoors you will need to rotate then to provide a decent quality of light to the entire plant ... remember that outdoors the sun rises and sets durring that time 90% of the tree/ plant gets light. our job is to mimic what mother nature has done so well.


First post and I'm already hated!! J/K and please remember that these are my test results on my own light meter and in no way do I mean to undermine anyone! Happy Bonsai-ing

Brian

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Brian,

Hello and welcome to the forum.
First post and I'm already hated!! J/K
Why do you say this unless you are trying to "stir the pot"? What does j/k mean?

Putting aside the technical aspects of your post, Ynot is not responsible for anything that Harry Harrington has written or posted on his website. Furthermore, how does this address the question by the OP? Junipers are ill suited to indoor culture for various reasons.

Norm

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Gnome wrote:What does j/k mean?
j/k = Just Kidding

LFS worker,

Welcome to the forum,

Your results hinge on several things that are not universal. IE: The type of glass you refer to as well as your location and methodology.

As well as several that are unknown to us. IE: The size/orientation of the window you refer to and again the specifics of how you measure.
LFS worker wrote: and please remember that these are my test results on my own light meter
IMO This is the most important part of your post.

And perhaps you should be more specific wrt where your specific claims of what is "absolutely incorrect" refer to.

There are facts that you dismiss with a broad statement as opposed to simply commenting on the glass statement.
[Which seems to be where your comment is directed and I don't understand considering you admittedly are not using typical glass.]
Citing the source{via a link} is a common courtesy as well.
HH wrote:Indoors, light levels are very poor. Though imperceptible to the human eye, light levels drop rapidly the further you are from a natural source of light.
Both of these sentences are indisputably true.

HH wrote:It is said that light levels halve every 50cm further from a window you are.
This also is well known. The formula may vary slightly but essentially the available lumens decrease equal to the square of the distance.
HH wrote: This means that for most tree species light levels are too low, even when stood on a bright window-sill.
I would have a difficult time calling this inaccurate.
LFW wrote: This is absolutely incorrect Through studies of light and UV filtering glass in the saltwater hobby it is KNOWN that this information is wrong.
Do much saltwater hobby outside?...j/k.
This 'KNOWN' information refers only to the sentence below and yet you seem intent on throwing the baby {previous three quotes} out with the bath water. Considering your reference using state of the art glass I have a hard time seeing the relevance of your 'experiment' to the average citizen.
HH wrote: It needs to be understood that glass filters out many of the UV rays that plants require for the process of photosynthesis; many trees species can fail to receive enough light on a south-facing window-sill even though the heat of the sunlight is burning their leaves.
LFW wrote: In plain daylight there is about 100,000 lumens of light this is with no cloud cover in late may in upstate New York.
That is excellent for Upstate New Yorkers...What relevance does it have for the rest of us?
HH wrote: The exact same sunlight at same time of year behind Low E tripple pane argon filled glass is about 45,000 lumens, and at 5 ' from the windpw there is about 44,000. These windows are one of the most energy efficient windows on the market as of current. There is more than ample light to encourage photosynthesis at these lumen levels.
Considering you left us to guess at the dimensions of windows and when you add that to the use of special glass it hardly equates to a typical environment that the participant here uses.
I think the article is accurate in not presuming that everyone has 'the most energy efficient windows on the market as of current' and I find that difference to be relevant to if your results are applicable for everyone else.
LFW wrote:/snip...but for argument sake the article is wrong.
For arguments sake...? Is there a reason you didn't take this issue to the author of the article?

Overall, I just don't see the your results as being relevant to an average person.

As Gnome notes wrt the OP, Indoors is not suitable for a juniper...

ynot

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hey all :) thanks for being kind I in no way mean to stir the pot and upset anyone. I'm the kind of guy who doubts everything and test to verify for myself :)

HH wrote:
Indoors, light levels are very poor. Though imperceptible to the human eye, light levels drop rapidly the further you are from a natural source of light.
Both of these sentences are indisputably true.

These are the statements I refer to as being absolutely incorrect .. Even up to 6 feet away from a window there is no lumen drop from 1" from the window. ( The light meter I am using at the high levels of lumens is only acurate to 1000 lumens , But for all intensive purposes the drop that is being mentioned would be fully detectable.)

50cm = 19.68503935inches . Now according to the article cited it is stating that evey 19"(being nice) the light would be halved. Now at the glass there are 44,000 lumens and at six feet away there should be appx 6,000 lumens folowing the formula that is stated halved every 50cm. This information could not be more wrong. As stated at six feet there is no lumen drop on my light meter. For the record the article is stating that a 20' skylight will have almost no light at the floor.

In regards to the light levels in the saltwater hobby. Alot of people grow nasty algae in aquariums that get even ambient sunlight. There are other probems that accompany this but the sun offers enough light through a skylight into a fish tank through the water to grow algae and coral.

LFS_worker wrote:

In plain daylight there is about 100,000 lumens of light this is with no cloud cover in late may in upstate New York.
That is excellent for Upstate New Yorkers...What relevance does it have for the rest of us?

I was simply offering a baseline for those whom have little understanding of light measured in lumens. With that information it is showing that the windows do offer a serious resistance to light. This information would make no sence to anyone if the scientific method would not be repeatable.

I will take this to the autor of the article but there again even he/she does not cite his/her works or where they got that information.

I don't profess to be a bonsai expert I'm still new to the hobby and I love it. But Light quality and quantity I do know my fair share about.

Thanks again for your kindness and I wish you all the best!
Happy bonsai-ing :)
Brian

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after talk with a friend of mine there are a couple missing details of my my posts

The light meter is a velleman DVM1300 lightmeter.
There was no humidity measurement outdoors or indoors. there should be minimal affect due to measurements being at about 6 feet.

the measurement of 6' was taken from center of a closed window with no screen covering the window along the hypoteneus following the angle following the sun.

the window is 48 x 36 side sliding window that is tint free. The window is relatively clean and cleaned using an alcohol based cleaner.

don't ask why this stuff is important but I guess it is. He states that My info is only good if it is fully repeatable and anyone anywhere could repeat the exact same experiment, and get similar results.

here is the window

ynot
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I really wish this weren't necessary...
LFS_worker wrote:don't ask why this stuff is important but I guess it is. He states that My info is only good if it is fully repeatable and anyone anywhere could repeat the exact same experiment, and get similar results.
LOL, No need to ask, He correctly refers you to aspects of the [url=https://en.wikipedia.org/wiki/Scientific_method]Scientific Method.[/url]

I am not sure what you were stating wrt Glass and UV rays but According to [url=https://www.uhs.berkeley.edu/home/healthtopics/sunsafety.shtml]here.[/url]
UC Berkeley wrote:UVA vs. UVB Radiation:

* UVA rays have longer wavelengths and are recognized as a deep-penetrating radiation. Long-term exposure can damage the skin's connective tissues, leading to premature aging and playing a role in the development of skin cancer. This type of ray is used in tanning salons. UVA rays pass through window glass.
* UVB rays have shorter wavelengths and are primarily responsible for sunburn (think B=burning rays) and skin cancer. UVB rays are blocked by window glass.
My understanding of UV rays wrt plants is fairly limited but some studies have suggested that excessive UVB does lower yields in some food crops.
This is not related to our topic but does suggest that it has a role to play in plants, Google for further info. The above quote addresses if [various] UV wavelengths transmit through glass.

Ok, From here on out it is not going to be pretty... You were warned :P 8).
...But Light quality and quantity I do know my fair share about.
If you say so...

This refers to info from the article.
I will take this to the autor of the article but there again even he/she does not cite his/her works or where they got that information.
[img]https://www.mysmilie.de/english/green/smilies/confused/5.gif[/img]...High School Physics
The light meter is a velleman DVM1300 lightmeter.
Yes, Thank you.
By the way that model measures in Lux not Lumens according to the [url=https://www.designnotes.com/downloads/Dvm1300GBNLFRDES.pdf]instructions[/url] where it is Officially called the 'DVM1300 - Luxmeter'. [url=https://www.designnotes.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=DVM1300&Category_Code=spm]This[/url] is it right?

[Not being mean here but as you measured 'lux' and referred to 'lumens' so frequently, I am curious] Did you:

Not notice?

Not understand the difference?

Not care?

Or an option I have left out.

Am I being presumptuous in thinking that you did not do any math to get to your numbers [From the measured Lux to the stated Lumens]?

I bet my presumption is safe considering that your stated daylight measurements closely match what the actual Lux #s would be.

Also a factor is that you did not post any light measurement conversions such as:

{ For our purposes; FC=Footcandle, Lux=Lux, Lumen=Lumen}

Since: 1 FC=1 Lumen/square foot,

and 1 Lux=1 Lumen/square meter,

and 1 square foot=0.0929 square meters

then;
1 Lux=0.0929 FC, and 1 FC=10.76 Lux

[Feel free to check the math] This means that 1 Lumen is equal to 10.76 Lux.

This puts your math off by a bit I should say, Which may not seem all that relevant but read on...
These are the statements I refer to as being absolutely incorrect .. Even up to 6 feet away from a window there is no lumen drop from 1" from the window. ( The light meter I am using at the high levels of lumens is only acurate to 1000 lumens , But for all intensive purposes the drop that is being mentioned would be fully detectable.)

50cm = 19.68503935inches . Now according to the article cited it is stating that evey 19"(being nice) the light would be halved. Now at the glass there are 44,000 lumens and at six feet away there should be appx 6,000 lumens folowing the formula that is stated halved every 50cm. This information could not be more wrong. As stated at six feet there is no lumen drop on my light meter. For the record the article is stating that a 20' skylight will have almost no light at the floor.
That blue bit above is my favorite part, :P 8) If you applied it to the quote it is in...It would be the truest thing IN the quote it's in.:lol:

For the record you either purposefully misrepresent or truly do not understand what he said in the article, The [url=https://csep10.phys.utk.edu/astr162/lect/light/intensity.html]Inverse Square Law of Physics[/url] disagrees with your assessment also

[url=https://www.starhop.com/High/SolInt-19.pdf]A student textbook explanation,[/url] Visit the [url=https://en.wikipedia.org/wiki/Inverse-square_law]Wiki page[/url] or google it for more info.
here is the window
Would it be possible to replace that advertisement with picture of the actual window in situ? [It also causes side-scrolling which is annoying...lol.]
...But Light quality and quantity I do know my fair share about.
If you say so... Still, It helps to actually be right when correcting someone, It helps a lot in fact.

Welcome to bonsai :D

ynot

LFS_worker
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very well done ynot you are truely a brain to be reconed with I have to go to lunch and I shall return. You are 100% correct in your math and quantum light theorys.

The conversion is correct also but I had a mental typo and kept typing lumens not lux ... for this I am sorry. funny the doctor I had checking everything even he didnt notice. LOL


Brian

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Brian,

:shrugs:...Nah,
Thanks man, But everybody has those moments where they don't shine so bright and everybody has moments where they simply shine...[img]https://www.mysmilie.de/english/green/smilies/characters/2/30.gif[/img]

It's only a moment man... Good or bad it's just life you know 8).

I am wrong about all kinds of stuff on a fairly regular basis, {WAIT: Nevermind, I am mistaken about that. ;) } I just don't post it. :P:lol:

Lucky for me I don't sleep :twisted: so I have time to research what ever topic it happens to be...lol

Keep posting :D

ynot

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The real fact of the matter is that his/her statement is incorrect. every 50cm does not half the light. Ive proved it myself, and anyone can test it for themselves. Light quality is not the reason for plants not doing well indoors.

I will post more later :) Been one heck of a day

Brian

ynot
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bonsaiboy,
I apologise for what happened to your thread, I will no longer continue to participate in this hijack.
LFS_worker wrote:The real fact of the matter is that his/her statement is incorrect. every 50cm does not half the light. Ive proved it myself, and anyone can test it for themselves. Light quality is not the reason for plants not doing well indoors.

I will post more later :) Been one heck of a day

Brian
Brian, I cannot emphasize enough that I am NOT interested.
As you insist on continuing to hijack this thread with the ERRONEOUS off topic posts, It only confirms to me that you are trolling. [EDIT: See next post for confirmation of this.]
The fact that you have not even bothered to discover the gender [much less the name] of the person your critiquing speaks volumes.

He stated this in his article:
It is said that light levels halve every 50cm further from a window you are.
It is hardly required that he be surgically precise with that statement, Just let it go.
LFS worker wrote:I don't profess to be a bonsai expert I'm still new to the hobby and I love it. But Light quality and quantity I do know my fair share about.
Take a moment to think about this:
Considering your demonstrated application/understanding on the topics that you...[As you say]
"do know my fair share about."
Imagine the anticipation of your wisdom on a topic in which you declare "I don't profess to be a bonsai expert I'm still new to the hobby

Let me be very specific about the amount of anticipation, There isn't any.
LFS worker wrote: Light quality is not the reason for plants not doing well indoors.

There is NOT any single reason for it, It has multiple factors of causation.

ynot

EDIT: Removed the plea to remove photo.
Last edited by ynot on Sun Jun 03, 2007 11:30 pm, edited 2 times in total.

LFS_worker
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so I guess that we are no longer harboring this statement from the please read before posting:

The Helpful Gardener is a relaxed and friendly place to post about gardening issues. Please help us keep it that way. Smile Unlike other forums, we do not tolerate personal attacks or insults. Anyone caught insulting another member will be permanently banned.

So I guess I have chosen the wrong forum instead of having this be a friendly conversation about Light quantity and quality it has turned into a I told you so thing.

FTR: Before I sign off A letter from the gentleman whom was the author of the article.

Thanks for your mail.
I am no expert on glass but I know we don't use the same glass in our
windows at home as you might in a fish tank :-P (Certainly in the UK we
use graded glass that filters UV).
That light levels are reduced indoors is well and widely known; while I
don't have any specific 'evidence' to hand to back this up (and won't
start to look now), there are too many other perfectly valid reasons
for
not keeping bonsai indoors that they make any arguments over glass
pretty
obsolete.
In all honesty I think the poster is just trying to validate keeping
his
trees indoors. On the other hand, if he wishes to ignore the advice of
possibly more experienced growers, he is very welcome, they are his
trees!
If he has experince of growing bonsai indoors and outside and has found
that the former is superior to the latter, fair enough, but I very much
doubt it :-P

Feel free to quote me.

Harry



Signing off My last post on helpfulgardener.com

Brian

ynot
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LFS_worker wrote:
So I guess I have chosen the wrong forum instead of having this be a friendly conversation about Light quantity and quality it has turned into a I told you so thing.
That's news to me.
It is science that tells all of us so, I am just the messenger 8).
The Helpful Gardener is a relaxed and friendly place to post about gardening issues. Please help us keep it that way. Smile Unlike other forums, we do not tolerate personal attacks or insults. Anyone caught insulting another member will be permanently banned.
Sorry dude, This is not relevant, Apathy by definition is not personal or insulting.

Brian,

To put it quite simply, It is unrealistic to expect anyone to throw you a party when you attack well known scientific principles with statements such as :
This is absolutely incorrect
These are the statements I refer to as being absolutely incorrect
The real fact of the matter is that his/her statement is incorrect. every 50cm does not half the light. Ive proved it myself, and anyone can test it for themselves. Light quality is not the reason for plants not doing well indoors.
Making statements such as the above [WRT what they refer to] when you have nothing to back them up and which are in fact completely refuted by a body scientific of evidence is not something that is rewarded, You know?

Perhaps a less confrontational introduction of the topic would lead to a more reasonable discourse.

To blame me for following in your footsteps with regard to the aggressive assertion of the facts involved subsequent to the discovery [by you] that the facts do not support your statements is moving the goalposts, Nothing more.

It is a strawman.

Having said that I am glad you posted the reply from Harry, Thank you.

ynot



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