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[DSLF] Digest Number 515
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There are 9 messages in this issue.
Topics in this digest:
1. Inexpensive Mass-Produced Night Sky Brightness Photometer
From: "doesper" <DaveOesper@aol...>
2. Help needed on raising awareness
From: Scott Griswold <griz@sky...>
3. cities with little or no streetlighting
From: Dave DeSantis <silverliner_12@yahoo...>
4. Re: Inexpensive Mass-Produced Night Sky Brightness Photometer
From: ctstarwchr@aol...
5. RE: cities with little or no streetlighting
From: "John Nusbaum" <jnusbaum@bellatlantic...>
6. Re: Inexpensive Mass-Produced Night Sky Brightness Photometer
From: "Terry McGowan" <lighting@ieee...>
7. Fw: [CFDS] Italian Amateur Astronomers' Union charter
From: "Karolyn Beebe" <keedos@earthlink...>
8. File - SplitLink.txt
From: DarkSky-list
9. Re: cities with little or no streetlighting
From: Mysids@aol...
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Message: 1
Date: Sat, 08 Dec 2001 19:13:46 -0000
From: "doesper" <DaveOesper@aol...>
Subject: Inexpensive Mass-Produced Night Sky Brightness Photometer
There is a tremendous need for an inexpensive, mass-produced night
sky brightness photometer. My company (Outdoor Lighting Associates,
Inc.) would like to add such an item to our product line, but I doubt
such a product yet exists, and I'm not yet convinced as to the best
way to go about developing one, though I am certainly willing to give
it a try.
Many of us would like to monitor trends in sky brightness, as well as
to compare the sky brightness at different locations. For example, I
am developing an observational astronomy course for a class size
limited to six students, and would like to have each student
regularly monitor sky brightness throughout the course.
What I envision is a (nearly) all-sky integrating sphere with some
sort of digital readout of sky brightness. Perhaps a sensitive
illuminance meter could be employed, but I'm not sure that any exist
that can read down to 0.001 fc (or less); even if such a unit exists,
I'm sure it will not be affordable.
I would like a unit that is affordable, easy to use, and that can
make measurements quickly. Am I asking too much?
Thanks,
David Oesper
Ames, Iowa
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Message: 2
Date: Sat, 8 Dec 2001 17:26:46 -0500
From: Scott Griswold <griz@sky...>
Subject: Help needed on raising awareness
Greetings everyone. I am looking for some help. I am working on my
photo archive web site and need some images for it. I have decided to
change the focus of my Goodlight/Badlight site and point directly to
examples of before and after shielding examples. The simpler the
example the better. I am looking for do-it-yourselfer type of things
as well that any home owner can do to help improve the effects of
their lights on their neighbor and commercial lighting retrofits. A
daytime shot of the fixture along with a before and after night shot
would be fantastic. At the very least a night time before and after
will do.
I am trying to bring this problem down to earth and explain simple
ways of correcting it. Please send an e-mail to griz@sky...
Attach the photo in JPG format. Please keep it under 100k. For each
image.
Thank you for any help you can give.
Peace & Dark Skies,
Scott Griswold
Woodstock, VT
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Message: 3
Date: Sat, 8 Dec 2001 14:44:24 -0800 (PST)
From: Dave DeSantis <silverliner_12@yahoo...>
Subject: cities with little or no streetlighting
I'm going to mention a few cities in the Bay
Area/Silicon Valley metropolian area which might be of
interest to you. There are two cities in the Silicon
Valley area (Santa Clara County) which only have very
limited use of streetlighting...only where
needed...the majority of the streets are dark and
illuminated only by the moon and stars and the porch
lights from the wealthy residences.
Plus at least one more city in the pensisula (San
Mateo County, the area south of San Francisco) is also
largely unlit with limited use of streetlighting.
Again this is a wealthy area.
Seems that many rich people do not like the aesthics
of streetlighting so they prefer that their streets
are to be left in the dark or at least lit by
incandescent streetlights at low levels (1000 lumens).
Also, there is one city that I am sure you all have
heard of, it's Palo Alto which is famous because of
Stanford. Palo Alto is 100 percent FCO when it comes
to cobraheads. Yes there are some acorns and teardrop
pendants, but the majority are cobrahead FCOs. Not one
semi-cutoff, NONE.
Hope this is of some interest for some of you.
Dave
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Message: 4
Date: Sat, 8 Dec 2001 18:02:14 EST
From: ctstarwchr@aol...
Subject: Re: Inexpensive Mass-Produced Night Sky Brightness Photometer
Hi Dave:
I am involved in a project to measure skyglow that is currently underway. We
applied for a grant last week to get some operating capital to begin
constructing ten sample *comparative photometers* specifically designed to
measure sky brightness. I am presently working out the finer details of the
mechanical aspects of the design and considering various jigs to create and
construct it.
The device we are working on will not include a digital readout in any
industry standard luminance or radiance measurement metric, however.
Something sensitive enough to do that would require a device like a
spectroradiometer with a very high resolution factor and extremely low signal
to noise ratio circuitry. No illuminance meter that I know of would be able
to measure sky brightness even in the worst imaginable conditions because
they are not sophisticated enough to handle this task.
A relevant measurement metric for skyglow might be scotopic radiant flux
stated in watts per square meter at a given wavelength or averaged over a
range of wavelengths rather than being stated in footcandles. Most of the
spectroradiometers I have seen can only measure down to 0.001 candela per
square meter, which would probably not even perk the scale on the meter when
measuring skyglow brightness. The following device available from
Biospherical Instruments is perfect for performing this task we are striving
for with an accurate degree of repeatability...
http://www.biospherical.com/products/wlr-2800.pdf
Looks pretty expensive though. More insight on the subject of measuring all
kinds of light can be gathered from the Light Measurement Handbook published
by International Light, Inc., found at:
http://www.intl-light.com/handbook/index.html
The device we are presently working on will have a high subjectivity factor
because it is a visual comparison device similar to what appeared in Sky &
Telescope about 15 years ago. Another similar device appeared in the
February issue. Due to their inherent lack of sophistication, the readings
from devices like these are subject to the eye sensitivity of the user rather
than giving a distinct reading of some kind on a meter that relates to a
known measurement metric.
In spite of that, it will be interesting to see what develops when measuring
same site areas under different weather conditions and comparing data to
other sites with similar data logs. It would be nice to be able to say just
how much scotopic spectral radiance is emitting from the sky though. That
could provide a relatively accurate and tangible indication of how much waste
is occurring just to generate skyglow and also measure the results of actions
taken to address it.
Clear skies and good seeing,
Keep looking up!
Cliff Haas
Chair Light Pollution Education
Astronomical Society of Greater Hartford
http://members.aol.com/ctstarwchr
In a message dated 12/8/01 2:14:55 PM Eastern Standard Time,
DaveOesper@aol... writes:
> There is a tremendous need for an inexpensive, mass-produced night
> sky brightness photometer. My company (Outdoor Lighting Associates,
> Inc.) would like to add such an item to our product line, but I doubt
> such a product yet exists, and I'm not yet convinced as to the best
> way to go about developing one, though I am certainly willing to give
> it a try.
>
> Many of us would like to monitor trends in sky brightness, as well as
> to compare the sky brightness at different locations. For example, I
> am developing an observational astronomy course for a class size
> limited to six students, and would like to have each student
> regularly monitor sky brightness throughout the course.
>
[Non-text portions of this message have been removed]
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Message: 5
Date: Sat, 8 Dec 2001 19:33:41 -0500
From: "John Nusbaum" <jnusbaum@bellatlantic...>
Subject: RE: cities with little or no streetlighting
Dave DeSantis said:
>Seems that many rich people do not like the aesthics
>of streetlighting so they prefer that their streets
>are to be left in the dark or at least lit by
>incandescent streetlights at low levels....
Excellent observation Dave!
I have a page on the Virginia Outdoor Lighting Taskforce website that is
a Sky Glow map of the entire Washington DC metro area. It documents
this very fact. Here is the link:
http://www.volt.org/Geteducated/sgpicpg1.html
There is only one reasonably dark spot (colored purple) in the whole
area ... It is centered on the Great Falls region ... the wealthiest
part of the metro area.
For what it is worth, it has been my observation that the wealthy tend
to believe strongly in what they are doing, don't take no for an answer,
and, have generally worked harder and smarter than the rest of us. In
short, they know how to get what they want.
Bright glary outdoor lighting is either an advertising scheme or a
mistake. There is no good reason for it.
If we want better lighting in our neighborhoods, in our cities, in our
states, or in our world, we have got to be willing to stick our neck out
and make it happen.
John Nusbaum
Herndon VA
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Message: 6
Date: Sat, 8 Dec 2001 19:22:02 -0500
From: "Terry McGowan" <lighting@ieee...>
Subject: Re: Inexpensive Mass-Produced Night Sky Brightness Photometer
That's a top-priority item for the IDA Research Working Group too, Dave.
Any and all ideas carefully and cheerfully evaluated.
Terry McGowan, Chair
IDA Research WG
----- Original Message -----
From: doesper <DaveOesper@aol...>
Sent: Saturday, December 08, 2001 2:13 PM
> There is a tremendous need for an inexpensive, mass-produced night
> sky brightness photometer. My company (Outdoor Lighting Associates,
> Inc.) would like to add such an item to our product line, but I doubt
> such a product yet exists, and I'm not yet convinced as to the best
> way to go about developing one, though I am certainly willing to give
> it a try.
>
> Many of us would like to monitor trends in sky brightness, as well as
> to compare the sky brightness at different locations. For example, I
> am developing an observational astronomy course for a class size
> limited to six students, and would like to have each student
> regularly monitor sky brightness throughout the course.
>
________________________________________________________________________
________________________________________________________________________
Message: 7
Date: Sat, 8 Dec 2001 23:08:43 -0600
From: "Karolyn Beebe" <keedos@earthlink...>
Subject: Fw: [CFDS] Italian Amateur Astronomers' Union charter
----- Original Message -----
From: <http://www.mizar-astro.freeserve.co.uk/mailsend.htm>
To: <liz@darksky...>
Cc: <CFDS@yahoogroups...>; <gregorh@cpre....uk>
Sent: Saturday, December 08, 2001 1:57 PM
Subject: [CFDS] Italian Amateur Astronomers' Union charter
>From Bob Mizon
dear IDA/CfDS/CPRE persons,
I have been sent the following 'charter for ethical skies' from Dr Carlo
Rossi, who has asked me to distribute it further. Comments to Dr Rossi,
please. <inqlum@uai...>
--------
ITALIAN AMATEUR ASTRONOMERS UNION
c/ or Università degli Studi of Padova
Department of Astronomy
Vicolo dell'Osservatorio, 5 35122 Padova
Internet site: www. uai.it
e-mail : HYPERLINK "mailto:info@uai..." info@uai...
National Light Pollution Committee
Via B.Medici 12 00053 Civitavecchia
P.E.: HYPERLINK "mailto:inqlum@uai..." inqlum@uai...
Tel.: 0766/507371
Charter of celestial ethics
A river of artificial light has cancelled out the stars. The night sky is
dying. Light pollution, the effect of light wasted upwards defies the
natural balance of day and night, light and dark. The charter of celestial
ethics is a behavioural code with the aim of saving the night sky.
General Terms
The starry sky , a visual and real image of the universe, is the heritage of
humankind;
let's not alter the day-night natural balance;
let's not send artificial light towards the vault of heaven;
let's respect flora and fauna;
let's not upset the psychological and physical balance of people;
let's not dazzle people and animals;
let's not destroy the astronomical culture inherited from our forefathers;
let's not hinder scientific observation and astronomical research;
let's save energy and the economic resources;
let's not reduce the chlorophyllian synthesis of plants.
Particular Terms
let's use shielded outdoor light sources;
let's light from the top downwards;
let's reduce bright emissions late at night;
let's not use excessive floodlights on monuments, churches, and areas of
archaeological interest;
let's send light only where people need it;
let's not project images towards the vault of heaven, on land or facades;
let's not use skybeams and laser beacons;
let's use monochrome lamps or slightly "hot" (pink/orange colours) and limit
their use;
let's use highly efficient lamps;
let's turn on/off fittings at civil twilight;
let's turn off fittings when not needed;
the terms of this charter should serve for the planning of exterior lighting
schemes;
let's respect and spread the celestial ethical charter;
Those who do not abide by the requirements of the celestial ethical charter
will be counted among the many destroyers and spoilers of the starry sky, to
their shame: will posterity remember their names?
August 2001
Edited by Eng.Carlo Rossi, National Light Pollution Committee of the
Italian Amateur Astronomers Union, Civitavecchia, Rome, Italy
Translation Prof. Renato Palomba, Amateur Astronomers Monti della Tolfa,
Civitavecchia, Rome, Italy, and Bob Mizon, British Astronomical Association
Campaign for Dark Skies.
--
Bob Mizon.
<http://www.mizar-astro.freeserve.co.uk/mailsend.htm>
38 The Vineries, Colehill, Wimborne, Dorset, BH21 2PX, UK.
International: +44 1202 887084 National (UK): 01202 887084
Coordinator, British Astronomical Association Campaign for Dark Skies
<http://www.dark-skies.freeserve.co.uk/>
Mizar Travelling Planetarium
<http://www.mizar-astro.freeserve.co.uk/>
Wessex Astronomical Society
<http://www.wessex-astro-society.freeserve.co.uk/>
Author: 'Light Pollution' (Springer, Nov 2001; ISBN 1-85233-497-5);
orders@svl....uk
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Message: 8
Date: 9 Dec 2001 10:33:37 -0000
From: DarkSky-list
Subject: File - SplitLink.txt
Forum Productivity Hint -- Long Internet Links
This is an automated message so please do not respond in
the general messages. Any questions may be directed to:
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It appears the YahooGroups system has recently undergone
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PLEASE DO NOT INCLUDE THIS CHARACTER when you paste split
links to your web browsers because it does not belong there
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Some Yahoo in the programming department has screwed up by
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With links that split you must post each line to your browser
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sure the first part that has already been pasted is not highlighted
in your address bar when the next part is pasted or it will cause
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Sorry for the inconvenience this has caused. There is nothing
that I can do about this problem with the available system
settings from a sysop standpoint.
Best regards,
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Message: 9
Date: Sun, 9 Dec 2001 11:24:55 EST
From: Mysids@aol...
Subject: Re: cities with little or no streetlighting
In the State of Florida, there is a closed (for the rich) municipality in Key
Largo called Ocean Reef. This is a well manicured community situated and
surrounded by mangroves and Atlantic Ocean barrier islands (the Keys)
ecosystems. Streetlights are nonexistent. Only a few lowly porches and
pedestrian walkways are illuminated by shielded incandescent lights and even
these are considered obnoxious. Of interest is the nightly illumination
by starlight. 3:00 am starlight illumination is very comfortable and you can
even read a newspaper without an artifical light. Distant vision is
unimpeded and superclear. Nocturnal wildlife abounds in the yards, gardens,
mangroves and bioluminescence (living marine organisms glowing the
phosphorous in their systems at night) radiates from the waters.
Unfortunately, only homeowners and nonresidents cleared by invitation may
enter. This community would be a good news article piece for LP education.
JNoles
[Non-text portions of this message have been removed]
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