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Hoondiggi95
member
Reged: 04/22/09
Posts: 11
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Okay, so I just got my Astromaster 90 AZ in the beginning of May and have been out for many viewing sessions. I live in a very light polluted area (just outside of Chicago) and have found the Jupiter and Saturn with no problem but am getting bored of that. So tonight I used my planishpere to find messier 13 and Andromeda. I was fairly impressed with the star cluster but it was very dim. Then I turned to Andromeda and it was very dissapointing. No structure or color whatsoever. Just a boring yellow thing that was so dim I had to squint to see it. Is there anything that I can do to improve deep sky objects without buying a new scope? Any eyepieces, filters, etc.? I am thinking that it might just be the light pollution but am not sure. Any help would be appreciated! Thanks!!!
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Achernar
Postmaster
Reged: 02/25/06
Posts: 5024
Loc: Mobile, Alabama, USA
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Small apertures and severe light pollution ensure deep sky objects are underwhelming, if they can be seen at all. I use a 10-inch from home to observe deep sky objects, and many of them are also very dim looking due to heavy light and air pollution. You have no other choice but to go to darker skies when the moon is not shining brightly also. Then you can at least see them better. If you want to even see hints of details on the dimmer ones, you'll need at least an 8-inch, and there's many deep sky objects that are a tough one for 12-inch telescopes from dark skies too. I would look for the Messier objects and the brighter NGC objects as well. There's a number of big but bright star clusters and some nebulae and galaxies that will be worth looking at from a dark site.
Taras
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15-inch F/4.5 Dob under construction
10-inch F/4.5 Discovery Dob
6-inch F/8 Homebuilt Dob
4 1/4-inch F/4 Homebuilt reflector
A whole bunch of eyepieces, filters and other accessories....
Two curious cats
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Hoondiggi95
member
Reged: 04/22/09
Posts: 11
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Can anyone give me list of deep sky objects that would look okay through my small scope and their location. Also would like a deep sky filter help on galaxies and clusters, as I know it helps nebulas drastically in light polluted skies. It is also called a skyglow filter.
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Scott K
Pooh-Bah
Reged: 09/13/07
Posts: 1407
Loc: Dallas, TX & Eufaula, OK
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Quote:
Also would like a deep sky filter help on galaxies and clusters, as I know it helps nebulas drastically in light polluted skies. It is also called a skyglow filter.
To be totally honest, the gas filter is far superior to a light pollution filter. What I mean is that from a major metropolitan area, there is so much light at all frequencies that it doesn't matter that you filtering most of it out - the OIII & HBeta lines that these filters allow to pass are overwhelmed by random lights from your surroundings.
Don't get me wrong, when I observed from my yard in Dallas, I would use a LP filter. (It's especially effective on relatively high surface brightness objects like many planetary nebula.) But the filtered views from my backyard paled in comparison to what I saw from a dark site - with no filter. (With a filter the same stuff was better still.)
Filters aren't going to help you much with galaxies or star clusters, unfortunately, but they will help with planetary and diffuse nebulae.
Some tips:
1. Join a club that has a dark sky site, and visit this as often as you can. You will be simply astounded.
2. Sometimes you have no choice but to observe from your home - I was in this situation for years. Blocking the ambient light around you as best you can helps a lot. (The goal is to get your eyes dark adapted.)
3. If you can find a darker, safe location near to your home, that is worthwhile too. Even in a big city, some places are darker than others. (Although in a big metropolitan area, you are just going to have to get out of town before you see a huge difference.) Anyway, you can't really escape local light pollution without driving a LONG way - but if you can get someplace where you can at least get fairly well dark adapted yourself, you'll actually SEE more.
Anyway, not trying to put you off of purchasing a light pollution filter. They are very useful tools! But they really can't fix overwhelmingly bad light pollution. (I was rather surprised myself to find that my LP filters were MORE useful in darker skies that had much, much less light pollution! That just seems - wrong!)
Best of luck to you.
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Doug Brown
sage
Reged: 02/24/06
Posts: 407
Loc: Fort Worth
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I know of only one thing you can buy to get better views of these deep sky things!
A tank of gas and go to a dark sky site.
The best thing to have is dark skies, and the next best thing is bigger scopes. It is like the old adage about a rising tide razes all boats equal. Well darker skies make all scopes better.
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Doug Brown
Though my soul may set in darkness, it will rise in perfect light;
I have loved the stars too truly to be fearfull of the night. ---Sarah Williams, 1868
10” Mead converted to Dob
Broken 20 x 70’s
7 x 50’s
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David A Rodger
sage
Reged: 08/12/03
Posts: 444
Loc: North Vancouver, BC, Canada
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Double stars, bright open clusters, some globulars and planetary nebulae are your best bets for in-city deep-sky observing. But I agree with others here that you need to get to a dark sky and, if possible, a bigger telescope. I observe mostly from a light-polluted major metropolitan area, and those are my primary targets with a CPC-1100, NP-127 refractor and a 10-inch Dobsonian.
Check out Rod Mollise's Urban Observers Guide. You'll find this book very helpful.
DAR
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Sky-Watcher 10-inch Dob
Orion 100mm ED and EON 120 refractors
Tele Vue NP-127 refractor
Celestron CPC 1100 SCT
Celestron Classic C-8
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JayinUT
I'm not Sleepy
Reged: 09/19/08
Posts: 940
Loc: Utah
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You could try the Urban Club list from the Astronomical League. The list is at the bottom of the page as a link, one for deep sky objects and one for double stars.
AL Urban Club List
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Jay in Utah
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Location: Lat: 40.514N Long: -112.032W
Mortal as I am, I know that I am born for a day. But when I follow at my pleasure the serried multitude of the stars in their circular course, my feet no longer touch the earth.
— Ptolemy, c.150 AD
My Blog
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Achernar
Postmaster
Reged: 02/25/06
Posts: 5024
Loc: Mobile, Alabama, USA
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You can use a broad or narrow band nebula filter, but the number of nebulae you could see will still be small compared to what will be visible from a dark site, or through a larger telescope. In fact, the bigger the telescope, the better a nebula filter works by virtue of the fact more objects benefit from a nebula filter. At that, you'll be looking at nebulae such as M-8, M-17 and M-27, but again all will be a lot better from a dark site. From a dark site you can even see the Veil Nebula with a 90mm scope, especially with a narrow band nebula. If you must observe from a city, a narrow band nebula filter is better than nothing but you also have to block glare from nearby lights as well. You can find a shadowed area in which to observe, or you can make a portable light screen like this one pictured below. It's not a substitute for a dark sky, but it will help. With a 10-inch I have looked at quite dim objects from my house this way. A light screen will also keep some of the wind off you too, but forget about setting one up if the wind is howling at 30 or 40mph.
Taras
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15-inch F/4.5 Dob under construction
10-inch F/4.5 Discovery Dob
6-inch F/8 Homebuilt Dob
4 1/4-inch F/4 Homebuilt reflector
A whole bunch of eyepieces, filters and other accessories....
Two curious cats
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Hoondiggi95
member
Reged: 04/22/09
Posts: 11
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I will try going up to one of the local parks where all of the trees are blocking the lights. But do you think that if I went to a very dark area the deep sky objects would look different and be brighter and more detailed instead of being dim little blobs? It could have also been bad though because of the moon or all of the lights on the houses that where close to me.
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Doug Brown
sage
Reged: 02/24/06
Posts: 407
Loc: Fort Worth
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Moon light and all light will wash out all galaxies and most nebulas. You may still find them but under better darkness you will see more no matter the size of your scope. Have fun with what you have and get to a star party somewhere and look through others stuff before any more scopes are thought about. Thing about joining a club as well.
Keep looking up
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Doug Brown
Though my soul may set in darkness, it will rise in perfect light;
I have loved the stars too truly to be fearfull of the night. ---Sarah Williams, 1868
10” Mead converted to Dob
Broken 20 x 70’s
7 x 50’s
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tatarjj
Pooh-Bah
Reged: 04/20/04
Posts: 1134
Loc: Austin, TX
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Hoondiggi, you have alot of things going against you right now.
1) Light pollution- frankly, everything except planets and a few very bright planetary nebulae are gonna look bad under light pollution.
2) Small telescope- when you combine light pollution with a small telescope, you're REALLY gonna limit your views. However, even a 90mm will show interesting details in many Messier objects if you get it out to a dark sky. A 90mm, operating at low power, will give spectacular views under a dark sky.
3)Inexperience- as one gains more experience in seeing faint objects, it becomes possible to see more and more details in them. A beginner will simply not be able to see the level of detail an intermediate or advanced observer will see
4) High expectations- considering all that you have going against you, you shouldn't expect to see much in DSOs. Expecting to see more than you actually do just leads to feeling let-down, and that is no fun at all. What you really need is to pick up some astronomy books for beginners, so you can get an idea of what you SHOULD expect to see. I am not up to date on what current books might be, maybe Nightwatch (that's what I've seen alot of people recommend, but never read it myself).
5) Location- not only is your backyard bad, but so is the entire state of Illinois if light pollution maps are to be believed. A truely dark sky is "grey" or "black" on light pollution maps- none of these exist in Illinois that I have ever seen. However, a "blue" or "green" zone should be within driving distance for you, and a green zone will be vastly, VASTLY improved over what you are currently using. I observed for years under a green zone, and it wasn't THAT bad. However, try to get out to a grey or black zone sometime and see what dark skies are REALLY like!
What you DO have going for you, if I am reading you correctly, is that you found M13 and M31 without the aid of computer pointing systems. This means you seem to have a pretty good grasp of the sky.
As far as filters go, get a UHC or OIII. The OIII will block even more light pollution than a UHC, but the OIII will also block some of a diffuse nebula's light. The OIII is the best filter for planetary nebulae, though. I personally haven't tested UHC vs OIII under light pollution, but under dark skies, the UHC outperforms the OIII on something like 65% of the diffuse nebulae, while the OIII outperforms the UHC on something like 98% of all planetary nebulae. Because the OIII blocks more light pollution and only barely loses out (IMO) to the UHC on many emission nebulae, then in fact, this trend may reverse under severe light pollution and the OIII could become the best all-around filter. Can anyone who observes USING BOTH FILTERS under light pollution confirm or deny this?
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John T.
Austin, TX
25" f/4.2 Dob
18" Obsession #701
4" Stellar Vue Achromat
8X56 Binos
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jmcdonald
Carpal Tunnel
Reged: 06/01/05
Posts: 1516
Loc: Tucson, AZ
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All of the above is good advice. Your main problem is light pollution. You've done better than most in finding M13 and M31 so that's a good start.
In addition to the recommendations above, see if you can track down the M57, the Ring Nebula, in Lyra. It will be very small but should look interesting at least and it takes magnification well.
Also M6 and M7 in Scorpio should at least be some fun.
You can also try some double stars. There are a number in Lyra that are interesting including the double-double - although you probably won't be able to split the two doubles. It's fun to look at all of the bright stars in Lyra because there are some pretty doubles with nice color contrasts.
In light polluted skies I stick to star clusters (globular or open), planets, double stars, and emission nebulae (with an OIII filter). Galaxies and reflection nebula all wash out.
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Jerel
Discovery 12.5" modified truss DOB
Garret 15x70 LW Binoculars
22-T4,13-T6
IDA Membership
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Achernar
Postmaster
Reged: 02/25/06
Posts: 5024
Loc: Mobile, Alabama, USA
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Yes, you will see them much better than from where you've been observing now. You should be able to find all of the Messier objects, a good many of the bright NGC and IC objects, even a few others. Messier had a telescope that was very inferior to yours and he had to make do with murky skies in Europe, so you're not as under-equipped as it may seem. Go to a dark site with no moon around on a clear night and you will be amazed at what a small telescope with good eyepieces can do. I have seen the Veil Nebula, the North American Nebula, and many Messier objects with an 80mm refractor. The Pleiades, Double Cluster, M-7 and other big open clusters are good objects from a less than stellar site. Even from a light polluted area you should be able to see the Ring and Dumbell nebulae at least some of the time. I went to a site that was still light polluted but much darker than my house. I routinely see objects with a 6-inch from dark sites that are utterly impossible with a 10 or 12-inch at home because of light pollution alone. Tatarjj also pointed out one other problem I overlooked, namely it takes time at the telescope to be a good observer. The more you observe, the more you see. That is how I am able to find objects from a light polluted area at all.
You should sign up for a regional and national star party, and take your telescope along. Look at everything you can think of with that telescope, and look through other people's telescopes too. Have a good time and enjoy some time under truly dark skies. I also encourage you to join a local club, which likely has access to some dark sites where your telescope can show you some deep sky objects. You are not going to see Hubble like views on them in most cases even with a large telescope. However, you should be able to see at least hints of their structure even with a 90mm refractor. You can see drawings here and at my web site as to how deep sky objects actually look like through telescopes. Some of those objects you will see drawings were devilishly hard to see with a 10-inch, even though I did go to a very dark site. Some of them were made with a 6 and a 4 1/4-inch telescope and many of these drawings were made in spite sometimes atrocious light pollution. Taras's web page
Taras
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15-inch F/4.5 Dob under construction
10-inch F/4.5 Discovery Dob
6-inch F/8 Homebuilt Dob
4 1/4-inch F/4 Homebuilt reflector
A whole bunch of eyepieces, filters and other accessories....
Two curious cats
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scopethis
professor emeritus
Reged: 05/30/08
Posts: 625
Loc: Kingman, Ks
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Somehow, any way possible, go to a darker location where you can see the stars of the Milky Way stretch across the sky. This should be your 1st objective.
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azure1961p
professor emeritus
Reged: 01/17/09
Posts: 731
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If I was stuck with a near-metro sky and my aperture was 90mm
I'd narrow my targets in terms of deepsky to emission nebula and planetaries. The benefit is you get to use effective filters that allow the light of the nebula to come through with the skyglow being impeded moderatly to impressively.
I'd get atleast a UHC for your skys. An OIII is wonderful but it also might be a little too dark for your aperture.
I dont know what a 90mm AZ is. If you can get down to 20x though, the OIII is good then for that aperture. Higher mags are more suited to a uhc perhaps.
The downside...
1. These filters are about a hundred bucks a piece.
2. They work so well on emission nebula like M42 and M17 and all planeteries that youll be sorry that there isnt such a thing as a "galaxy filter" or star cluster filter. Some folks like the less restrictive nebula filters for this, but the gain is nothing like m57 for example through a UHC or OIII.
Change your targets, get a neb filter. Boy you'll be happy.
Pete
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Edited by azure1961p (08/14/09 07:43 PM)
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Hoondiggi95
member
Reged: 04/22/09
Posts: 11
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Thanks for all of the help! I will try to head out to darker skies soon but tonight I will have to observe from my backyard again. Any tips on what objects to search for? M13 even looked pretty cool from my skies, anything else like that? Also I am only 14 but can I still allowed to join a club or star party?
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azure1961p
professor emeritus
Reged: 01/17/09
Posts: 731
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M57...really nice - ring nebula
If you want something a little more challenging - but still "bright, go with NGC6210 - excellent tho tiny planetary nebula
My fav plnetary of summer besides those two is NGC 7027.
The above planetary nebula i gavce you are good surface brightness objects. But they are deepsky so they are still dim. The trick with the last two, and they are bright is to use enough magnification to show them as not stars. At low power they will appear starlike. Around 100x u should do fine. Even 70x is good but be careful and scan slow.
The above objects are roughly the brightness of the core of m31 - kinda. Surface brightness can be a very technical measure. I'm giving you a shrug and a best guesstimate.
I love these objects though.
Pete
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Edited by azure1961p (08/14/09 08:18 PM)
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Hoondiggi95
member
Reged: 04/22/09
Posts: 11
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Also so my eyes will stay used darkness I will tape some paper over my flashlight so when I am looking at my planisphere to find my way around i am not blinding myself. I think that was another problem last night.
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MikeRatcliff
Pooh-Bah
Reged: 06/12/04
Posts: 1327
Loc: Redlands, CA
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Those are good suggestions.
You can usually find UHC filters on the used market for $80 or so.
On the Urban List mentioned in a previous post, there are some challenging ones even on that list. For example NGC 129, the first entry, isn't that easy for me in my backyard, and isnt' really a beginners object in my opinion.
I'd try out the ones with the lowest (brightest) magnitudes first. This time of year, mid to late summer: M6, M7, M8, M11, M13, M17, M22, M24, M25, M27, M39, M57. A mix of globular and open clusters and a few nebula. The UHC will help with the nebula but not the clusters.
Fall and winter you can add M34, M35, M36, M37, M38, M41, M42, M44, M45, M46, M47, M67 and the "Double Cluster" NGC884/869 which are all brighter open clusters.
Good luck and happy hunting,
Mike
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16" f/4.9 dob, 1.25" Paracorr, 24 TV Widefield, 18 Circle T ortho, 13 Nagler T6, 12.5 UO ortho,
9 Circle T ortho, 2x TV Barlow 1.25"
Edited by MikeRatcliff (08/14/09 08:19 PM)
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Hoondiggi95
member
Reged: 04/22/09
Posts: 11
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I just found out that M57 is in lyra and am so suprised because I was using that constellation all night to find my way around the sky and didn't even know it was there. I will definitely look at the nebula tonight though.
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