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George Normandin
July 23rd 03, 04:31 AM
Last year at Stellafane a friend & I found that our CCD'ing laptop was
annoying nearby visual observers. I would think that "star party etiquette"
would have to be that bright laptops are not acceptable.

So: How does one use a laptop or other PC at a star party or popular
observing site? Anybody have suggestions on how to cut the screen light down
to levels acceptable for visual observers? Keep it under a box? :)

George Normandin

Chris L Peterson
July 23rd 03, 05:55 AM
On Wed, 23 Jul 2003 03:31:29 GMT, "George Normandin" >
wrote:

> Last year at Stellafane a friend & I found that our CCD'ing laptop was
>annoying nearby visual observers. I would think that "star party etiquette"
>would have to be that bright laptops are not acceptable.
>
> So: How does one use a laptop or other PC at a star party or popular
>observing site? Anybody have suggestions on how to cut the screen light down
>to levels acceptable for visual observers? Keep it under a box? :)

A box isn't a bad idea, and would give good dew protection.

First, make a screen filter out of a couple of layers of neutral gray limousine
window tinting. Second, design a night vision color scheme that works well for
you, featuring mostly reds and dark colors most likely. Finally, if you want to
go the extra mile try adding a privacy filter (people use them on airplanes to
keep their seat mate from seeing the screen.) They block off-axis light, which
is the real problem with modern LCD displays. Do all that, and not only will
nobody complain, but your own night vision will be fairly well preserved.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

Roger Hamlett
July 23rd 03, 09:18 AM
"George Normandin" > wrote in message
...
> Last year at Stellafane a friend & I found that our CCD'ing laptop
was
> annoying nearby visual observers. I would think that "star party
etiquette"
> would have to be that bright laptops are not acceptable.
>
> So: How does one use a laptop or other PC at a star party or popular
> observing site? Anybody have suggestions on how to cut the screen light
down
> to levels acceptable for visual observers? Keep it under a box? :)
>
> George Normandin
Four stages:
1) Set the screen brightness as low as possible.
2) Select a largely 'red based' colour scheme.
3) Add a darkish filter material over the screen (Rubylith), possibly even
two layers.
4) Add dark 'edges' to the screen, standing about 1"-1.5" above the existing
screen edge.
This last is really the 'critical' one. A lot of LCD screens, 'leak light',
at small angles. Hence you can have your screen set to give a darkish image
when looked at nearly perpendicular to the screen, and bring this down even
lower with filters, but then find that if you look at a shallow angle to the
screen, the light is several times brighter than the actual image. It is the
leakage, that is the real 'pain'. If you sit the screen effectively in the
bottom of a 'tray', this stray light gets massively attenuated (ideally you
wand these edges lined with something like flock).
Some of the modern screens, with very wide 'viewing angles', have less of
this leakage, but more and more designs, conversely, don't let you turn the
intensity down very far...
There are also special filters sold which are meant to block this stray
light, but I have never found them to be as effective as the edges.

Best Wishes

Jim Barclay
July 23rd 03, 10:24 AM
Two ways to solve this:

Have laptop facing _away_ from the visual group, or do what I do: Place
the lappy in a big thick cardboard box with some plastic sheeting over
same to stop dew soaking into box. Paint inside box with flat black
paint and have red light and screen down to a min. brightness.

Jim

George Normandin wrote:

> Last year at Stellafane a friend & I found that our CCD'ing laptop was
> annoying nearby visual observers. I would think that "star party etiquette"
> would have to be that bright laptops are not acceptable.
>
> So: How does one use a laptop or other PC at a star party or popular
> observing site? Anybody have suggestions on how to cut the screen light down
> to levels acceptable for visual observers? Keep it under a box? :)
>
> George Normandin
>
>

Davoud
July 23rd 03, 12:42 PM
George Normandin:
> Last year at Stellafane a friend & I found that our CCD'ing laptop was
> annoying nearby visual observers. I would think that "star party etiquette"
> would have to be that bright laptops are not acceptable.
> So: How does one use a laptop or other PC at a star party or popular
> observing site? Anybody have suggestions on how to cut the screen light down
> to levels acceptable for visual observers? Keep it under a box? :)

*****

Keep it under a laptop privacy/sunshield hood. Follow this link
<http://www.google.com/search?as_q=&num=100&hl=en&ie=ISO-8859-1&newwindo
w=1&btnG=Google+Search&as_epq=laptop+hood&as_oq=&as_eq=&lr=&as_ft=i&as_f
iletype=&as_qdr=all&as_occt=any&as_dt=i&as_sitesearch=&safe=images> and
you will find a number of sources from which to purchase the Hoodman
model. Read a review at
<http://www.steves-digicams.com/hoodman_e2000.html>.

Davoud

--
usenet *at* davidillig dawt com

Cliff Wright
July 23rd 03, 10:21 PM
George Normandin wrote:
> Last year at Stellafane a friend & I found that our CCD'ing laptop was
> annoying nearby visual observers. I would think that "star party etiquette"
> would have to be that bright laptops are not acceptable.
>
> So: How does one use a laptop or other PC at a star party or popular
> observing site? Anybody have suggestions on how to cut the screen light down
> to levels acceptable for visual observers? Keep it under a box? :)
>
> George Normandin
>
> Good Day George.
I have another suggestion.
Do a search for a programme called "powerstrip" on Google. It is available
from some sites as freeware. Using that on my Dell laptop I can adjust the
screen settings to give almost any level of illumination you might want. It
also allows control of individual colours and clour temperature if
required.
It is very useful for Patrick Chevally's "Cartes du Ceil" programme which I
use instead of setting circles on my 8" scope I use for field work.
I use a digital level for altitude and a home made "circle" on the base
which gives azimuth. Thus my Dob mount has effectively got setting circles.
Hope this helps.
Good seeing!
Regards Cliff Wright.

Chris L Peterson
July 23rd 03, 10:43 PM
On Thu, 24 Jul 2003 09:21:51 +1200, Cliff Wright >
wrote:

> I have another suggestion.
>Do a search for a programme called "powerstrip" on Google. It is available
> from some sites as freeware. Using that on my Dell laptop I can adjust the
> screen settings to give almost any level of illumination you might want. It
> also allows control of individual colours and clour temperature if
>required.

The problem is that any modern LCD panel requires some kind of external
shielding. This is because they leak light at oblique angles. You can turn off
every pixel on the screen, making it as black as is physically possible through
the electronics, and the screen will still look like a searchlight once you are
dark adapted. What is needed is the ability to greatly reduce the brightness of
the fluorescent backlight. I haven't seen any laptops that let you dim them all
the way do nothing.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

Gregory Phillips
July 24th 03, 01:05 AM
I simply bought some tinted plexi-glass at a local Home Base store and cut
a couple of pieces the size of the LCD screen. It turned out that two stacked pieces
were needed once your eyes got totally adapted. It actually worked quite well,
give it a try.

On Wed, 23 Jul 2003 03:31:29 GMT, "George Normandin" > wrote:

> Last year at Stellafane a friend & I found that our CCD'ing laptop was
>annoying nearby visual observers. I would think that "star party etiquette"
>would have to be that bright laptops are not acceptable.
>
> So: How does one use a laptop or other PC at a star party or popular
>observing site? Anybody have suggestions on how to cut the screen light down
>to levels acceptable for visual observers? Keep it under a box? :)
>
>George Normandin
>

---
Gregory Phillips Seattle, Washington, USA

George Normandin
July 27th 03, 06:23 PM
"David Nakamoto" <> wrote

> I got something from an art store called Rubellite (spelling?), which is a
> thick
> cellophane-like stuff that is thick enough......

Thanks guys for all of the neat ideas!

I'll try one or more until I get to what I want. Maybe I'll buy a few of
those red sheets and offer them to others.

However, if I never post here again you will know I failed and some irate
visual observer at Stellafane or the Black Forest Star Party, etc, killed
me! :)

George Normandin

David Nakamoto
July 28th 03, 05:09 AM
There's a way to avoid death. Point to the guy using a bright green laser
into the sky and when the attention shifts, pack up everything and leave in
a hurry ! :-)

--
----------------------------------------------------------------------
Never be afraid of trying something new for the love of it.
Remember... amateurs built the Ark.
Professionals built the Titanic!


----------------------------------------------------------------------

"George Normandin" > wrote in message
...
>
> "David Nakamoto" <> wrote
>
> > I got something from an art store called Rubellite (spelling?), which is
a
> > thick
> > cellophane-like stuff that is thick enough......
>
> Thanks guys for all of the neat ideas!
>
> I'll try one or more until I get to what I want. Maybe I'll buy a few of
> those red sheets and offer them to others.
>
> However, if I never post here again you will know I failed and some irate
> visual observer at Stellafane or the Black Forest Star Party, etc, killed
> me! :)
>
> George Normandin

Matthew B. Ota
July 30th 03, 10:38 AM
Put a sheet of red rubylith or a cut rectangle of #2423 red plexiglas ove the
screen.
The plex can be held in place with strips of velcro.

I will be at Stellafane this year. Come and see me and I may have an extra piece
of plex for you.

George Normandin wrote:

> Last year at Stellafane a friend & I found that our CCD'ing laptop was
> annoying nearby visual observers. I would think that "star party etiquette"
> would have to be that bright laptops are not acceptable.
>
> So: How does one use a laptop or other PC at a star party or popular
> observing site? Anybody have suggestions on how to cut the screen light down
> to levels acceptable for visual observers? Keep it under a box? :)
>
> George Normandin

--
--------------------------------------------------------------
Matthew B. Ota
Orange County Astronomers Astroimagers SIG
http://www.ocastronomers.org/
Telescopes In Education (TIE)
http://tie.jpl.nasa.gov/tie/index.html
Jet Propulsion Laboratory Saturn Observation Campaign
http://soc.jpl.nasa.gov/index.cfm
--------------------------------------------------------------