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[DSLF] Digest Number 1449

There are 7 messages in this issue.

Topics in this digest:

      1. Re: green design
           From: glennlaser@aol...
      2. Re: "blue" radiation - incandescent vs. fluorescent
           From: Jan Hollan <jhollan@amper....muni.cz>
      3. Re: Rocket Science
           From: ctstarwchr@aol...
      4. Re: Re: green design
           From: ctstarwchr@aol...
      5. Watch out for those planners
           From: Jack Liebenthal <jackl@tetontel...>
      6. La Silla LP
           From: "Fabio Falchi" <fabio_falchi@yahoo...>
      7. Re: Watch out for those planners
           From: ctstarwchr@aol...


Message: 1         
   Date: Tue, 14 Sep 2004 08:35:11 EDT
   From: glennlaser@aol...
Subject: Re: green design

I can't find any reference to "Green Lighting Designer" in the article.  
Please clarify.
Glenn Heinmiller, LC
In a message dated 9/13/2004 09:52:35 AM Eastern Daylight Time,  
DarkSky-list@yahoogroups... writes:

This  program looks like it might be worth looking  into.


Has  anyone here been certified as a Green Lighting Designer?  Can 
anyone  provide more information about what being green certified 
has done for  your career or your employer's bottom line?


[Non-text portions of this message have been removed]


Message: 2         
   Date: Tue, 14 Sep 2004 19:41:49 +0200 (CEST)
   From: Jan Hollan <jhollan@amper....muni.cz>
Subject: Re: "blue" radiation - incandescent vs. fluorescent

> http://www.rednova.com/news/stories/2/2004/09/10/story003.html

... a very good media report from that breakthrough conference,
 -- thanks to the excellent organisers and participants like Russel Reiter
and Russel Foster. From the presentation of the second one I can offer an
image of action spectrum of melatonin suppression by non-image-forming
visual system, they are files act*.jpg within the directory
 -- the reference for human spectra are given in the larger images.
I have just the data for the first two papers, ``Brainard'' and ``Thapan''
one, they are shown as blue and red points in the Russel Foster's graph.

In spite the spectrum being not known very well, its crude shape
agrees for all authors and for humans and mice (and probably for another
mammals as well). The differences in the violet wing are not very serious,
absorption in the human lens makes the sensitivity to fall very steeply
toward 390 nm (the curve shown there is rather just for some opsin, not
for the whole eye including the yellowish lens).

Computation of melatonin-suppressing radiation can and has surely be done,
using this spectra, for wavelengths in the whole region 390 nm to 600 nm,
as the sensitivity curve is as broad as the scotopic or photopic one.
I advise to you to try it, Dave. I'll send you some formula describing the
curve including the violet brahch.

Apart from computation, the ``melanoptic'' lumens  (``melanoptic'' may
be a premature designation, it's still not sure what the pigments are,
even if melanopsin is the chief candidate, another ones may play a role
too) can be measured by ordinary CCD cameras with Bayer matrices. For two
types I've demonstrated that on a poster at the conference, see
 within the http://amper.ped.muni.cz/noc/english/

(in the poster, reference to the source of scotopic and photopic curves
is missing, they the files  logssvl2e_1.txt and scvle.txt taken from
         Stockman and Sharpe
    URL: http://cvision.ucsd.edu/
 -- the lens filtering effect is given there too, as lensss.txt)

I suppose to start measuring the blue-green (it's probably better name
then melanoptic) lumens (luxes, nits) of various sources soon, by our Fuji
S5000, to have some new results for the Graz conference.

> Back to the theories of radiometry versus photometry, would it be
> possible for you to provide any insight on why the data that Glen
> received included the */1000 lumens* metric in the spectral data?

Cliff, per 1000 lm of emitted light, there are some watts emitted as well
(say, for a source with efficiency of 100 lm/W it's 10 W).  They are
emitted in UV, visual, short and long infrared. Just a fraction is emitted
in the blue-green radiation, and that's the number. Multiply it by the
total lumens of the source.

The metrics is just as for the luminaires: there are candelas per 1000
lumens given, describing specific luminous intensities. If the source
has 10000 lm, multiply these numbers by ten to get numeric values of
actual luminous intensities.

healthy natural night,


Message: 3         
   Date: Mon, 13 Sep 2004 13:30:51 EDT
   From: ctstarwchr@aol...
Subject: Re: Rocket Science

It is great when nearby residents care enough to make the time it requires to 
take a stand and express their concerns about new construction in force.  I 
have seen many of these stores that have been constructed in Connecticut, Mass, 
Vermont, and New Hampshire that use only full cutoff lighting and fully 
shielded floodlights to illuminate the facade of the building.

Wal-Mart's corporate headquarters is located in Arkansas, so they may have 
done it right by preference to serve as a 'showpiece' considering the negative 
press with people all over the country speaking out objecting to the enormous 
impacts from new construction on undeveloped land from corporate giants in 
their areas.  They can and will be a good neighbor if the zoning department has 
the courage to give them acceptable guidelines.  Too often town officials cave 
in to fear of loosing that huge corporate tax revenue on their grand list.

I have designed outdoor lighting for several Wal-Marts by exceeding minimum 
RP-20-98 recommendations for low impact, meaning what I installed was not as 
bad as what I could have used had I followed RP-20-98 to its maximum limits.  
The company's corporate design criteria does not say anything about shielding 
fixtures and only provides the illuminance limit requirements they expect on the 
site.  Their criteria are extremely reasonable if compared to most other big 
box operations and it falls below the limits of maximum lighting in RP-20-98 
for basic needs with a max of 3 footcandles in their specs.  With a 20:1 
max/min ratio and a 0.2 fc horizontal minimum the max level is 4 fc in RP-20-98.

It is bad practice to judge a whole corporate structure based on one or two 
badly designed sites, but that fractional influence might be obnoxious enough 
to engulf our entire world if it is installed in our back yards.  Ya wanna see 
a reason to complain?  Take a look at the conditions in my back yard every 
night coming from an empty building that was abandoned over 2 years ago and I 
have been complaining about to my town officials requesting them to enforce the 
town's lighting code since 1986!


The town manager tells me she likes to walk at night and feels safe because 
it is bright, but facts are that two pedestrians have already been killed in 
the past 15 years while walking along the road with that glare blasting into 
drivers eyes, so go figure.  I am convinced by this example and many others that 
idiots are all around us and educating them is not always possible.  
Impeachment works a lot better if you can get the public support!  >:-)

Clear skies and good seeing,
Keep looking up!

Cliff Haas
Author Light Pollution Awareness Website (LiPAW)


In a message dated 9/13/2004 11:54:58 AM Eastern Daylight Time, 
lr722@swbell... writes:
FWIW, our new WM Stuporcenter in Little Rock, AR is the most dark-sky 
friendly big box store in town.  FCO lighting on short poles.  Even the 
loading dock and rear wall packs are FCO. 

This only happened because nearby residents objected to the giant store 
being built in a neighborhood that's very close to a beautiful state 

[Non-text portions of this message have been removed]


Message: 4         
   Date: Tue, 14 Sep 2004 16:26:31 EDT
   From: ctstarwchr@aol...
Subject: Re: Re: green design

Hi Glen:

I could not find any reference to GLD in the article either.  That was
why I was compelled to pose the question.  The reference to becoming 
Green Certified appeared in the "Green Design" teaser found at this URL.


It is the last article under the Key Issues heading.  I haven't had time 
to check the USGBC web site.

Clear skies,


In a message dated 9/14/2004 1:17:13 PM Eastern Daylight Time, 
glennlaser@aol... writes:

> I can't find any reference to "Green Lighting Designer" in the article.  
> Please clarify.

[Non-text portions of this message have been removed]


Message: 5         
   Date: Wed, 15 Sep 2004 02:19:18 -0600
   From: Jack Liebenthal <jackl@tetontel...>
Subject: Watch out for those planners

I just learned that the Planners Dictionary, from the APA, the American 
Planning Association, has the following definition of Full Shielded Light 
Fixture and that it is interchangeable with Full Cut Off [according to them].

*A hooded light fixture that is shielded in such a way that light rays 
emitted by the fixture is [sic] projected below a horizontal plane running 
through the lowest point on the fixture where light is emitted.*

Every light fixture that is pointed sort of down meets the definition 
because [some, it doesn't say all] light rays are projected below a 
horizontal plane.  I can imagine that some FCO lights might not be 
considered "hooded" and might fail the definition.  Moreover, the light 
seems in their mind to be emitted in a different place from where the light 
rays are emitted.

If you propose an ordinance, make sure that the definitions don't fall into 
the hands of a planner.  I found this out at a hearing on my ordinance 

Real question -- does anyone see a legal problem with a reference by an 
ordinance to IES for definitions?

Teton Valley Dark Skies
Seeking to preserve the natural features of Teton Valley nights
More at
Jack Liebenthal

[Non-text portions of this message have been removed]


Message: 6         
   Date: Wed, 15 Sep 2004 15:50:09 +0200
   From: "Fabio Falchi" <fabio_falchi@yahoo...>
Subject: La Silla LP

An interesting image of the glow of La Serena as seen from more than 100 km
away is here:
Paradigmatic of the mean astronomer thought is the worring about reassuring
us about the quality of the observation taken in La Silla:
'This is the reflection of the city lights of the city of La Serena, about
100 km away and too faint to disturb observations of celestial objects high
above La Silla.'
They should have pointed out the growth of La Serena LP, instead!
Dark Skies, if they still exist somewhere.
Fabio Falchi


Message: 7         
   Date: Wed, 15 Sep 2004 09:07:10 EDT
   From: ctstarwchr@aol...
Subject: Re: Watch out for those planners

In a message dated 9/15/2004 4:24:29 AM Eastern Daylight Time, 
jackl@tetontel... writes:

> If you propose an ordinance, make sure that the definitions don't 
> fall into the hands of a planner.  I found this out at a hearing 
> on my ordinance proposal.
> Real question -- does anyone see a legal problem with a reference 
> by an ordinance to IES for definitions?


You made an excellent point.  The *definition* of full cutoff has 
been bastardized by many people who write zoning codes or ordinances,
and professional planners with AICP certifications are no different.  
It seems some misinformation, likely the results after reviewing many
technically incorrect lighting codes, has crept into their publications 
department also.  

The question may be, is bad or inaccurate information in the hands
of lighting laymen better than no information at all?  In this case 
it seems to be in my opinion, simply because serious attention is 
finally being paid to the LP problems we face today.  Can they and
we do any better?  Of course, and further education is the answer.

The definition at the APA web site is the most common technical error 
I have seen creep into codes written by well meaning people, but what 
was published is the definition of *fully shielded* lighting.  Your 
sharp eyes and heightened awareness picked up on that immediately as 
well as the potential implications of improper aiming I'm proud to say.
Great work!  Now the question remains how can we possibly reduce the
potential for outdoor lighting abuse in a more effective way?

Your concerns are absolutely justified regarding the *sort of downward*
aiming criterion, but there is no simple answer to this conundrum due
to many different types of fixtures available.  For example, what would 
one put in a lighting code to assure the Providence full cutoff post top 
by Architectural Area Lighting, or similar fixtures by others, perform to 
provide the cutoff classification they were designed to achieve?  Unless 
installed in a vertical position neither a post top nor a bollard performs 
to the cutoff standard it was designed and advertised to achieve.

It may not be true and hopefully others will challenge this statement, 
but I do not believe any simple *engineeringesque* (i.e., layman friendly 
language) phrasing in a lighting code can provide 100% assurance that all
code enforcers, plan reviewers, lighting designers and fixture specifiers 
or installers will interpret with the same understanding, but we might be 
able to minimize the propensity for misunderstandings by sticking with 
industry standards like IES cutoff definitions and using good graphics 
that clearly explain the relationships between angles and emissions 
allowed.  See the Photometry folder in the Photos section of this Forum 
for some that might help assure a better level of understanding occurs.

If an enforcement issue finds its way into a court of law, sticking 
with the industry standards like IES cutoff classifications rather 
than using home brewed criterions like *fully shielded* or a *percentage 
of zonal fixture lumens of uplight* will always stand a better chance 
of surviving legal scrutiny because they should be commonly accepted 
and well understood throughout the lighting design and manufacturing 

Human perception is a really funky thing because even some of the 
largest luminaire manufacturers and IES Fellows who write technical 
articles for LD+A and other publications either do not, cannot or 
will not interpret, comprehend, or convey the IES cutoff definitions 
correctly when pen gets put to paper.  This may be due to a legacy of 
prematurely published standards appearing in the previous iteration 
of RP-8-83 that compels many people to conveniently omit the *at or 
above* criterion for intensity beginning at both the 80 and 90 vertical 
degree terminators up from nadir that define the glare and uplighting 

Illuminating engineering is not an exact science, and in many ways it 
continues to evolve inferring we don't know everything yet and are 
still learning as we go.  The RP-8-00 has the only *correct* definitions 
for the three IES cutoff classes that attenuate intensity, so be careful 
to assure those are the definitions you apply if you are going to specify 
these criteria in a legal document like a zoning code or local ordinance.
You can find these definitions explained at the Citizens for Responsible 
Lighting (CRL) web site in the Tech section of the Engineering tab and 
the Luminaires section under the Links tab at:  http://www.crlaction.org

Perpetuating misinformation like what you discovered the APA doing at 
their web site may not have been intentional on their part, but this 
does not provide justification for the authors, nor does it preclude 
compounded problems that occur by the time the codes get written and
the fixtures go into application then introduce enforcement challenges.
Rather than demonize them I try to praise their efforts and do what I 
can to further educate them in a constructive way with the hope more 
effective solutions can be achieved.

Municipal, regional or state codes striving to assure the acceptable 
equipment is installed and operates as it was designed to perform is 
not an unrealistic expectation, but writing specifications in a way 
that is both technically correct and is easy enough for average people 
to understand properly is a significant challenge.  Like Edison said 
when he was striving to produce a successful incandescent bulb, we
now know 8,000 things that don't work.  That bogus definition for full 
cutoff is one of them, and its perpetuation into more codes needs to
stop and be improved so added confusion is not generated in the future.

I prefer to see instructions included on lighting plans that provide 
clear and explicit guidelines for installers and plan reviewers where 
post tops are assured to be installed vertically plumb and flat lens 
fixtures are verified to be level in two perpendicular intersecting 
planes to assure the fixtures' performance will *resemble* what appears 
in the manufacturer's photometric reports.  A diagram that I created 
several years ago is in the Photometry folder of the Photos section 
to help others clearly understand what this means.

This also helps code enforcement officials realize what is necessary 
to verify when they visit sites after construction has been completed.  
Due to tolerance stackups, many different methods applied for testing 
luminaire photometrically in the labs, and lamp manufacturing variance, 
every link in the chain of assembly develops dynamics that practically 
assure it is unlikely any fixture will ever exactly match its photometric 
report, but hopefully they will come pretty close.  Maybe this helps to 
clarify why I always say illuminating engineering is NOT an exact science.

The fact is, even if a code clearly specifies no outdoor area lighting 
other than full cutoff are allowed, unless the fixtures are actually 
installed in a level position **as it relates to 90 vertical degrees 
in the photometric reports provided by the manufacturer** with zero 
degrees of upward tilt, roll and spin, the fixtures may not perform 
to the IES cutoff classification they were designed and advertised to 
achieve.  This is a very important issue that needs to be addressed 
comprehensively in any codes that are developed to assure conformance 
can be achieved and enforced.

A classic example is fast food restaurants and convenience stores who 
install full cutoff fixtures that could provide outstanding aesthetic 
appeal with more than adequate performance, but they tilt them upward 
at vertical angles of 20 degrees or more above horizontal so harsh 
glare shines in everyone's eyes.  THEY believe this will attract more 
customers like moths to their establishments.  Certainly that practice 
never improves safety or security for either the establishment or its 
visiting patrons.  If more people boycotted because of that and wrote
letters to the owners objecting to this practice we might eventually 
see significant change in that trend mandated at the corporate level.

If we remember the four IES cutoff classifications are only *performance 
standards* and NOT luminaire hardware features it opens a new world of 
awareness and understanding about the potential implications that can
occur when the hardware (luminaire) is not installed properly.  A fully
shielded fixture will produce no direct uplight if installed correctly, 
but it may not work as well as a fixture offering full cutoff performance 
when it comes to reducing visible glare or light trespass impact because 
no attenuation of intensity at and above vertical angles of 80 degrees 
are specified with fully shielded fixtures.  They are also not recognized 
as an industry standard, but that criterion opens the field of available 
products to all four cutoff classes with the sole provision they emit no 
light above the horizontal.  There are both advantages and disadvantages 
to this shielding criterion.

To complicate the issues even more, the IES terminated their Cutoff
Committee a few months ago and the Lighting Research Center has been 
awarded the RFP from IESNA to redefine their existing cutoff standards, 
so it is anyone's guess right now what future classifications will soon 
bring to the horizon, or perhaps maybe more of a concern, what degree 
of uplight will be permitted to emit ABOVE the horizontal plane in direct 
emissions?  I personally hope they do more to address emissions below 80 
vertical degrees affecting the non-target areas occurring on the house 
side of the fixtures to help further mitigate light trespass problems.

Most people here would like to explore the feelings of others on this 
issue.  Please generously share your thoughts and ideas on what we can 
possibly do to improve the language in lighting codes to assure they 
effectively reduce the amount of direct uplight and light trespass.
How can we also improve the average person's level of understanding at 
the same time?  Might there be an easier way to explain things that 
common practice of the past has continued to overlook?  Please share 
your ideas and thanks for listening.

Clear skies and good seeing,
Keep looking up!

Cliff Haas
Author Light Pollution Awareness Website (LiPAW)


[Non-text portions of this message have been removed]


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