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NEWMOON
member
Reged: 08/16/08
Posts: 15
Loc: Woodridge, Illinois, USA
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Have been reading forum posts about light shades. Also light filters. If you use light filters why would you need light screens (shades)?
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Celestron Nexstar 130mm
Celestron Omni 2x Barlow
Lasermate Collimater
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vinnie
Latinist
Reged: 01/05/08
Posts: 1446
Loc: Queensland, Australia
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G'Day New Moon and welcome to CN!
I am a bit unclear as to what you mean here so I could be way of line, still it wouldn't be unusual for me.
I guess you are referring to a light shade or screen that is a barrier like a tarp or similar around your set up to cut down incidental light from lamp posts, passing cars etc, as opposed to fitting a filter to the light train of your scope.
I could only say that filters are used to enhance viewing of various objects and under given conditions. Despite some claims, I have my doubts that any filter is actually going to help overcome glare from a streetlight outside your house.
As far as the so called "LP" filters are concerned, I have no experience as I don't have light pollution here, but my understanding is that these are to help with sky glow, as opposed to direct light, where you would try to shield your scope with a barrier.
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Silicon Owl
scholastic sledgehammer
Reged: 11/25/05
Posts: 943
Loc: Waimea, Hawaii
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Filters may help with light pollution but they do nothing to help you against direct light shining on you. Direct lights will prevent your eyes from adapting fully to the dark. The human eye becomes many times more sensitive to light in full dark and amateur astronomers have learned to use that.
Light shades to block local lights, or simply finding a site that has no direct lights will help in viewing, even in a somewhat light polluted area. The back yard may be far better than the front driveway if you can escape direct lights.
My driveway is a good (and horrible) example. I have dark skies, you can see the Milky Way very nicely overhead. But there are also several streetlights, one right across from my driveway. The driveway is awful for visual observing as it is far too bright with direct light, my eyes have no chance to dark adapt. It works fine for astrophotography, where I can use filters to eliminate the yellow light from the LPS streetlights. Get just 100yds outside the neighborhood, and block and direct lights, and I have skies darker than most of the continental US.
The newly planted, and carefully situated, royal poinciana just needs to grows another six feet or so and my driveway will be a lot darker.
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Andrew Cooper
Personal Website and CN Gallery
Handmade 18" Dob / NS11GPS / 6" RFT / 90mm APO / TV-76 ...and a twin 10m
"I have loved the stars too fondly to be fearful of the night." --Sarah Williams
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d1anderson
sage
Reged: 10/11/07
Posts: 268
Loc: North Central Texas
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Hi and welcome to CN. In answer to your question. Like Vin said, a shade will block the light from entering your eye thereby allowing your eyes get closer to dark adapted while a filter will prevent some light from passing through your telescope. If you have the correct filter certain objects are much more easily seen.
Clear Skies
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Dewayne
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Z12 dob
MEADE DS2130AT NEWT 494goto
MEADE NG60 REFRACTOR
A Bunch of supplied Eye Pieces
The more you look the more you'll see! 
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Joe Aguiar
professor emeritus
Reged: 02/10/07
Posts: 728
Loc: Toront,Ontario
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you guys answered that perfect nothing more to add
Joe
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Protheus
Vaguely offended
Reged: 09/01/07
Posts: 4658
Loc: Illinois, US
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Actually, I think that certain filters (a UHC, for example) will have a noticeable, though small, effect on direct glare coming into the objective of the instrument. If the light is behind you, though, it's not going to do any good at all. Getting away from the light will be much better either way.
Chris
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"To tread the sharp edge of a sword;
to run on smooth-frozen ice,
one needs no footsteps to follow..."
"Well, people sometimes ask me 'how did you get involved in astronomy?' I said 'I got born, what's your problem?'" -- John Dobson
"In discussing the large-scale structure of the cosmos, astronomers sometimes say that space is curved, or that the universe is finite but unbounded. Whatever are they talking about?" -- Carl Sagan
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NEWMOON
member
Reged: 08/16/08
Posts: 15
Loc: Woodridge, Illinois, USA
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Thanks to all for the information. It seems night vision is most important. But if you were to use a lp filter would you recommend and get more use from a narrow band (UHC) filter to start with.
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Celestron Nexstar 130mm
Celestron Omni 2x Barlow
Lasermate Collimater
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GeorgeDuke
Pooh-Bah
Reged: 04/24/03
Posts: 1173
Loc: PARADISE! (So.Florida)
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These filters are for different situations. You need to read up on them and decide which one you will use the most.
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George
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LX200GPS 203mm f10
StellarVue SV102ED2 Feathertouch Ser#0018
Celestron 130mm f15.4 Mak
LXD75 GOTO with Orion 16" pier extension
Desert Sky DSV1 dual head ALT-AZ mount
Baader Hyperion 8mm ,13mm, 21mm and 8-24mm Zoom + FTRs
2" GSO ED barlow, Orion 2" Prism Diag. 2" WO Dielectric
Chinese Scopes, Chinese Eyepieces, Chinese Wife, Love them all!
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THEPLOUGH
Nailed Again
Reged: 01/11/08
Posts: 3957
Loc: Carlisle, Cumbria, ENGLAND
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By light shade do you mean a dew/lightshield that fits over the end of the scope. These are good for preventing any stray light hitting the back of the mirror. The only filter I use is a MOON filter.....
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Geoff...
Nexstar 8SE -- 9X50 RACI Finder scope... 6.3 F/R.-- 13 & 17mm Hyperion EPs.. 25mm Celestron E- Lux EP.. 2X Celestron X-Cel Barlow----- Celestron solar filter + A few bits and pieces..
Never give up on any one..... MIRACLES happen every day....
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wrather1
AstroBear
Reged: 10/25/05
Posts: 2935
Loc: Dallas, Texas
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FWIW, I live in a SEVERLEY light-polluted area. In order to see some of the faint-fuzzies, I have to use light-block panels, a shroud, AND an LP filter sometimes!
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"Don't worry about what telescope you own, or its quality. Just get out under the night sky, and enjoy God's wondrous universe." - T. M. Back
Meade RCX400-12 on JMI trolley "Ursa Major"
TMB 130SS on EQ6 PRO "Ursus Polaris"
Orion ED80 "Ursa Minor", WO ZS66ED "grab-'n'-go"
Canon EOS 30D (Hutech), Meade DSI, Philips ToUcam Pro
North Texas Clear Sky Chart
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NEWMOON
member
Reged: 08/16/08
Posts: 15
Loc: Woodridge, Illinois, USA
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Thanks for the additional info. Can see time and research will bring answers. Did order a 2x Barlow and a UHC which I will use for nebulae mostly. THEPLOUGH you mentioned Dew/Light shades, can you point me to some info on these? By the way I own a Celestron NextStar SLT 130mm, which came with a 25mm and 9mm EP. Have recently got a Lasermate collimator which seems to work well. I guess I'm looking to find the basic equipment to start this hobby. Already want more magnification hence the Barlow. Don't want to go crazy just be prepared.
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Celestron Nexstar 130mm
Celestron Omni 2x Barlow
Lasermate Collimater
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