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roccodm
member
Reged: 01/15/08
Posts: 36
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I am using an ar-5 and for the life of me i m51 continues to elude me- i was out a couple of nights ago and had no trouble with m81,m82 m10 and m12- from the books i look at m51 is given a wow factor of 5 out of 5 so i think it should be easy to spot- i am thinking that maybe i need an ultra block filter or perhaps a sky glo filter although my skies are not bad- all advice welcome-clear skies rocco
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FirstSight
Carpal Tunnel
Reged: 12/26/05
Posts: 2516
Loc: Raleigh, NC
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Are you trying to find M51 against any even modest degree of suburban light pollution? If so, you should realize that for all its fame as one of the brighter, "showcase" spiral galaxies, it is notoriously susceptible to being not just washed out, but difficult to find in even moderately light-polluted conditions, unless you have fairly big aperture (such as a 10" or 12" dob). And even then it can be horribly washed out and a minor chore to find, compared to its appearance at a dark site, which is magnificent.
Though M51 is not nearly as susceptible to wash-out as M101 (which is perhaps the most notorious prominent galaxy of all for fainting to invisibility against even the slightest suburban skyglow), it is equally frustrating for being located in what sure SEEMS like it should be such an obvious, easily findable location, yet can be so maddeningly elusive against any light pollution. What's doubly maddening about M51 and M101 is that they're both so teasingly, almost trivially easy to find from a true dark site, even in binoculars.
It took me quite awhile to find it last night under good (for summer North Carolina suburban) conditions in my 90mm APO refractor, and it was just a very dim, subtle smudge then that I would never have found or recognized, had I not visited it many times before.
M81 and M82 OTOH, are enough brighter compared to M51 that behind only M31 (Andromeda), they are the most hardily resistant galaxies to light-pollution, even in modest aperture (they still can look very washed-out compared to their dark site appearance). Also, insofar as M10 and M12 go, globular clusters (especially the brighter Messier globular clusters) are vastly more resistant to becoming too washed-out to be easy to find under moderate light pollution than are galaxies. GC's resolution and beauty suffers from light pollution, but they remain relatively easy to find, provided helpful starhopping landmarks are still visible.
And NO, filters (including skyglow or ultrablock) won't help at all with making galaxies more visible, since galaxies are broad-spectrum emitters and all you accomplish with a filter is to proportionately reduce the already dim amount of light visible from them to just the bands passed by the filter. Objects which are helped by these types of filters differentially pass a higher percentage of their light within the bandpass spectrums allowed by the filters. A skyglow filter might, however help some if you're directly being blinded by the harsh glare of e.g a streetlight - it just won't help any with galaxies against generalized background suburban skyglow.
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Chris M., aka "First Sight"
Orion XT12i Dob with Moonlite CR-2 focuser
WO Megrez 90 refractor on UniStar Light mount
Nikon 10x50 Binoculars
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MaxTheHitman
super member
Reged: 12/11/07
Posts: 104
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heeeeeeelllllo 4 days ago I set the challenge to find the M51 it eluded me also for a couple of month and I failed to get it until this lucky time I knew I saw something hazy and I was able to distinguish the spiral a little and the two cores. The sky was probably moderately dark. M51 really needs a dark dark site!.. Iam using a 6"refractor FL:750
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6" acrhomatic refractor F/5
CG5-GT
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HaleBopper
sage
Reged: 01/14/08
Posts: 259
Loc: Great White North
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M51, along with M1, gave me fits for years. My skies are usually around 4.2, and that makes nabbing M51 that much harder.
I used to have a 4.5" reflector, it was a Tasco department store scope I had as a kid. I was always able to star hop to M81 and M82 using it. The view was not spectacular, but I saw those galaxies. I used to think that M51 would be a cinch. It was maddening, all the time I spent, trying to find it. I just could not. Today I have an 8" SCT, and I can see it from my yard, but only the nucleus as well as the nucleus of the companion. No spiral structure to be seen. You really have to be at a dark site to boost contrast or M51 will be washed out.
I'm of the opinion that filters won't help, for the reasons stated in one of your responses. However, there have been claims that the Baader Moon and Skyglow-Filter enhances deep sky galaxies. At least that is what their advertisment states. I have this filter, but I have not tried it on galaxies yet to test this calim.
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8" SCT CG5 mount
Canon Digital Rebel 400
Kodak Easyshare 2.0 Megapixels
5, 8, 13, 17, 21, 24mm Orion Stratus
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RAKing
scholastic sledgehammer
Reged: 12/28/07
Posts: 819
Loc: Clouds-ville, Virginia
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Quote:
Though M51 is not nearly as susceptible to wash-out as M101 (which is perhaps the most notorious prominent galaxy of all for fainting to invisibility against even the slightest suburban skyglow), it is equally frustrating for being located in what sure SEEMS like it should be such an obvious, easily findable location, yet can be so maddeningly elusive against any light pollution. What's doubly maddening about M51 and M101 is that they're both so teasingly, almost trivially easy to find from a true dark site, even in binoculars.
Wow. Truer words were never spoken. These galaxies can be terribly difficult to study. There are many nights where M51 and its buddy, 5195, are faint glows and M101 could be mistaken for a dim star.
Keep trying. I did and was finally rewarded with a view of the spiral structure of M51. Definitely worth the effort.
Ron
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Time spent looking at the stars is added to your life.
Orion XT10i / Moonlite CR2 -- The New "Time Machine"
"Hi Def" TV-102
C925-CF SCT
Ethos and Naglers
GM-8 GEM / A-P Portable Pier
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vanhooglesnort
member
Reged: 02/18/08
Posts: 42
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Glad to hear this sucker is hard for other city-folks...I thought it was just me! I got M81-82, and M51 was pointed toward a darker part of the sky. Guess I'll table that one untill my next trip to darkness.
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Supercharged ETX-125PE
90mm f/10 Homegrown Achromat
Meade 4000 Super Plossls
One Lonely Nagler 16mmT5
10X50 Nikon Binos
Phenix City AL Clearsky Clock
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roccodm
member
Reged: 01/15/08
Posts: 36
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Thanks for the resonses looks like i am going to have to take a smaller scope and head out to a good dark location. think i will save my money and invest in a good ep instead of the filters clear skies rocco
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David Knisely
Postmaster
Reged: 04/19/04
Posts: 6783
Loc: Beatrice, Nebraska
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FirstSight posted:
Quote:
And NO, filters (including skyglow or ultrablock) won't help at all with making galaxies more visible, since galaxies are broad-spectrum emitters and all you accomplish with a filter is to proportionately reduce the already dim amount of light visible from them to just the bands passed by the filter. Objects which are helped by these types of filters differentially pass a higher percentage of their light within the bandpass spectrums allowed by the filters. A skyglow filter might, however help some if you're directly being blinded by the harsh glare of e.g a streetlight - it just won't help any with galaxies against generalized background suburban skyglow.
Well, I can't really agree with a blanket statement like this. When used properly (correct power range (3.5x to 9.9x per inch of aperture) and with full dark adaptation), certain broadband "light pollution" filters *do* help some galaxies, at least at a modest level. They filter out some of the glow from Mercury and Sodium vapor lighting while passing a lot of the rest of the visual spectrum. They do tend to saturate to some degree for moderate to severe levels of skyglow, but under mild skyglow levels (ZLM 5 and fainter), they will help some galaxies stand out to some degree. I found this to be the case on Sunday night while observing M51 with my NexStar 9.25 inch SCT. At 78x and 98x, the galaxy looked somewhat better when using the Lumicon Deep-sky broadband filter than it did without the filter. Some galaxies tend to be rather bluish in the outer arm regions, so the passband of the Deep-sky filter tends to let much of that light through while still blocking the stuff we don't want. The level of improvement is fairly mild to be sure, so some people judge these broadband filters to not be worth the money, but some people do like the extra kick in contrast which these filters can sometimes provide. Here is what the Deep-sky does to a nearby sodium vapor streetlight:
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David W. Knisely
Hyde Memorial Observatory
http://www.hydeobservatory.info
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JakeT93
member
Reged: 06/28/08
Posts: 177
Loc: Williamstown, NJ
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I had trouble last night too...couldn't get it. Tonight in South NJ is clear, and I found it. Hop from Alnitak, and in your finder is another little star, go left a tiny bit, and start scanning, you'll see a grouping of stars, go a little more, and you'll see two lights above another faint-ish star. It was pretty faint, I was scanning the area in my 25mm for about 30 seconds, saw a star, and two small patches....then gasped...then said holy !@#$, then put in the Barlow with the 25mm, and it looked great! Surprised, as the galaxy was in the glow of Philly. M63 was great too, and it was a little brighter. Above Cor Caroli, is a group of stars resembling what I thought of as an awwor, go up a little, and slightly turn the scope right. Start scanning for a little patch next to a star. Dave, do they make specific filters for galaxies?
Havn't seen M81, or M82 yet, but really want to. Tried but failed on the Sombrero, but got in these 2 galaxies. Pretty cool knowing what you are seeing is over 50 million LY away, and outside your own galaxy...nice!  Never thought I'd find them...Galaxies are REALLY something else arn't they.
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-Jake the Snake
My equipment:
Orion DSE 10" Light Bucket!
10x50 Finder and ebay bracket
40mm GSO Plossl
32mm Celestron Plossl
2x Antares Barlow
25mm and 6.7mm Meade 3000 Plossls
Orion Explorer II 10mm and 17mm Kellners
Orion SkyGlow Ultrablock
Antares ND25
70 M's Obsreved
All Planets seen
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David Knisely
Postmaster
Reged: 04/19/04
Posts: 6783
Loc: Beatrice, Nebraska
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Quote:
I had trouble last night too...couldn't get it. Tonight in South NJ is clear, and I found it. Hop from Alnitak, and in your finder is another little star, go left a tiny bit, and start scanning, you'll see a grouping of stars, go a little more, and you'll see two lights above another faint-ish star. It was pretty faint, I was scanning the area in my 25mm for about 30 seconds, saw a star, and two small patches....then gasped...then said holy !@#$, then put in the Barlow with the 25mm, and it looked great! Surprised, as the galaxy was in the glow of Philly. M63 was great too, and it was a little brighter. Above Cor Caroli, is a group of stars resembling what I thought of as an awwor, go up a little, and slightly turn the scope right. Start scanning for a little patch next to a star. Dave, do they make specific filters for galaxies?
Havn't seen M81, or M82 yet, but really want to. Tried but failed on the Sombrero, but got in these 2 galaxies. Pretty cool knowing what you are seeing is over 50 million LY away, and outside your own galaxy...nice! Never thought I'd find them...Galaxies are REALLY something else arn't they.
Well, the Lumicon Deep-sky filter does help some galaxies a little, as does the DGM Optics GCE "Galaxy Contrast Enhancement" filter, although under light pollution, the Deep-sky filter might provide just a tad better rejection of the skyglow. However, once the skyglow gets to a certain level, neither filter will help very much on galaxies. Clear skies to you.
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David W. Knisely
Hyde Memorial Observatory
http://www.hydeobservatory.info
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OldDeadOne
Pooh-Bah
Reged: 09/09/06
Posts: 1083
Loc: West Virginia
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That's why I'm a Galaxy and DSO man,I love looking at galaxies and DSO's. M51 is awesome in my 10"!
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Bert O'Dell
PROUD GOTO USER
LX200 10" Classic
various meade plossi's eyepieces
Konig MX70 40mm" eyepiece
11mm T6
7mm T1
Insane under a full moon
I duck from Iron Skillets
Charleston WV clearsky
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MikeRatcliff
Pooh-Bah
Reged: 06/12/04
Posts: 1107
Loc: Redlands, CA
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M33, the Pinwheel Galaxy in Triangulum, is another deceptively tough one for light polluted backyards.
Magnitude of 5.7! With that number alone you would expect something really easy. But the light is spread out over a large area. It will be coming up in the next few months.
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16" f/4.9 dob
Tele Vue Plossls 32,25,20,15,11
13 Nagler T6
10.5 Pentax XL
Brandon 32, 16
12.5 UO ortho, 9 Circle T ortho
2x TV Barlow
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wysky
member
Reged: 05/27/08
Posts: 51
Loc: wyoming
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I love the Whirlpool galaxy. On good nights I can easily see the arms spiraling around the core with it's NGC partner. Equally enjoyable is going to the galaxies in Virgo-M87 etc. Seeing 3 or 4 galaxies at a time in the eyepiece is amazing.
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cpc1100
2x televue big barlow
ethos13mm
2" ultima 32 and 17mm
lumicon filters planetary, polarizing, and OIII
C5 spotting scope
11x80 celestron bino's
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xfile101
professor emeritus
Reged: 12/08/07
Posts: 739
Loc: Ocean Gate, NJ
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M51 is very tough in LP skies. Many, many years ago I had viewed this galaxy in my Astroscan and remember it as wonderful and easily found. Now, some, 15-20 years later, the LP has just about washed it out. In fact for the last year or so, I haven't been able to find it but about a month ago I finally found it and it doesn't look anywhere near what I remembered in the Astrscan. LP has killed it all I get is 2 fuzzy "stars". I have never seen M101 even though I KNOW it was dead in the center of the FOV (I use a COL and it is spot on). Keep searching, you will eventually find them, persistance is a big factor in this hobby. I have been looking for the Veil for something like 20+ years and FINALLY saw it the other night, so keep plugging. 
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Orion XT8I
Celestron 114EQ Firstscope
Meade 70mm
Astroscan
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Old Dinosaur
scholastic sledgehammer
Reged: 05/08/07
Posts: 839
Loc: Out in the sagebrush
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Wysky, where abouts are you? My CSC shows where my obs is.
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WRS Observatory
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mv1000
super member
Reged: 05/27/07
Posts: 114
Loc: WI
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Here's a comparison for you. July 4 I spent the evening doing a decent first light with my Megrez 90. I was in mag 6.2 skies. I saw spiral structure in m 51. A hint of spiral structure in m 101. Mottling in m 82. The brighter globulars were sprinkled with individual stars. Not to the core obviously, but I was impressed.
Now compare that with my 14.5 Starmaster in my light polluted backyard. m 101 is pretty much invisable. m 51 shows maybe a hint of spiral structure. Same with nebulae. I won't even waste my time. What I'm trying to say is, I would rather do my observing in a dark sky with a small scope than in town with even the biggest dob. Instead, I stick with doubles, planets, and maybe the moon.
Now, the Starmaster in a dark sky? Ummm, I don't have words for that.
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Starmaster 14.5 Hybrid/Sky Tracker
TV 60
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MaxTheHitman
super member
Reged: 12/11/07
Posts: 104
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I can hit M51 but usually iam off to the north and drifting somewhere so I go south by a few degree maybe 2 to get this M51. Seriously I can barely see this spiral shape but due to humidity is killing me!!! M101 remains a nightmare to me that I can never find...:(( I end up tracking andromeda !what a beautiful Galaxy and M81,M82!
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6" acrhomatic refractor F/5
CG5-GT
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PeterSurma
member
Reged: 08/24/06
Posts: 84
Loc: Heidelberg, Germany
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Hi,
the answer is pretty straight: forget galaxies if you cannot reach a dark sky with faintest stars of (at least) 5+ mag. For impressive pictures you need 6+mag skies. Galaxies are the most demanding objects in terms of night sky brightness. The reason is simple: the number of photons that they emit on a square-arcsec area of e.g. their spiral arms is pretty close to the number of photons that are coming down from the sky itself (again per square-arcsec area). So they simply drown in the sky. You can also not get much help with filters, because night sky brightness and galaxies have similar light (spectra) and no filter can discriminate the one from the other very well.
Two classes of objects exist which are very different:
- stars (and star clusters, mostly open ones) stick out more easily as they concentrate all their photons on a very small area
- emission nebula can be MADE to stick out by using filters that suppress normal light and let through the specific nebula light, so again the contrast is enhanced above normal
You might also draw another conclusion from this: if you own a reasonable scope already (say 8" or even better), and you are having trouble with seeing galaxies: don't invest into more aperture, but binvest into (transportation +) seeing better skies (get a good site and a good car :-).
Get to good skies and you'll easily + impressively see galaxies.
Good luck,
Peter
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Web: http://www.eyes4skies.de/home_EnglishVersion.htm
Edited by PeterSurma (07/07/08 08:57 AM)
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