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Unsatisfying first attempts at viewing DSO

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#1 jrschmidt2

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Posted 04 August 2020 - 10:50 PM

After a few sessions of viewing the easy objects (moon, Jupiter, Saturn, Venus), I thought I should expand my horizons and try for a few "simple" DSO.  Things didn't go so well.  I am using a 102 Mak on a very basic EQ-1 mount.  After some newbie struggles star hopping I have thus far managed to find / view the open "easy" (?) open clusters M13 and M22.  Both came out as faint blurry patches, far cries from what I might have (naively?) been hoping for.  I realize the setup is basic and I am willing to make an investment to so that I can further enjoy this hobby, but I'm a bit at a loss of what is limiting the viewing right now -- and guessing could be a very expensive experiment!

 

Possible issues:

 

1) Light pollution:  Viewing from what I think are roughly Bortle 5 skies (outer suburbs of Madison, WI), although I do have some direct street lights to deal with.  I have installed a dew/light shield to block direct light into the scope but didn't notice much of a difference.  I read that a CCD/camera might help overcome this, but I'm not sure that this is the limiting factor.

 

2) Resolving power:  With only a 4" scope, should I expect more than a fuzzy blob?  Yet I would think that I could resolve at least a FEW bright stars out of the blur.

 

3) Light collection:  I realize that aperture gets me more light collection as well, but a simple CCD would presumably also help with this with via longer exposures.

 

Advice from some seasoned experts as to what I should be expecting and the most effective "upgrade" path would be useful.  Note that I am well aware that moving to darker skies would be ideal, but given 3 young kids I am looking for a setup that might be able to give acceptable results for simple DSO in typical "suburban" settings so I can actually USE my setup on a regular basis.

 

Thanks so much for your advice!



#2 scottinash

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Posted 04 August 2020 - 10:57 PM

You really should be enjoying more detail. What eyepieces are you using? When you view the moon how great is your focus/clarity? 
 

Here is a useful reference/comparison that I had saved compliments of our CN host “Astronomics” I believe:

 

 

 

Attached Thumbnails

  • 763DE98B-A349-4BCB-ABE4-15FAC2FDBB59.jpeg

Edited by scottinash, 04 August 2020 - 11:14 PM.

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#3 Xtatic

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Posted 04 August 2020 - 11:51 PM

That is a great illustration of what to expect.  It's not my thread but thanks for it.  


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#4 havasman

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Posted 05 August 2020 - 12:19 AM

You have chosen excellent targets. M22 & M13 are spectacular. The problem right now is likely the moon is full and that washes out a lot of objects. Keep observing and see if over the next couple of weeks things don't show marked improvement.

 

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Edited by havasman, 05 August 2020 - 12:20 AM.

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#5 Glory Eye

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Posted 05 August 2020 - 12:31 AM

I don't want to be a discouragement at all to you, but I have to concur with the thumbnails in post no.2 as it is almost perfectly representative of my direct experience. I started with a 5" aperture reflector and could not get anything as good as the picture labeled 4.5" telescopes. I "rushed to large aperture", purchased an Orion 16", and now I get excellent views of globulars similar to the picture of the 14".



#6 SeattleScott

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Posted 05 August 2020 - 12:55 AM

Keep in mind M13 and M22 are globular clusters, NOT open clusters. So they need magnification to resolve them. If you have dark skies and use 150-200x magnification, you are in for a treat.

In city skies, or full moon skies, they disappoint.

Scott
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#7 Redbetter

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Posted 05 August 2020 - 01:04 AM

Welcome to CN.  

 

The first and most obvious problem is that you are attempting to view DSO's from the suburbs of a city of 250,000 during a full Moon.  For a small telescope that is a big order even for bright globulars. Direct streetlights mean glare to you as the observer, so you are probably not dark adapting significantly either.  You will likely need to improvise some sort of observing hood if you continue to observe with the lights glaring on you.  Even so, it should improve somewhat when the Moon is out of the way.  Obviously, getting away to some rural skies without the Moon will improve things even more.

 

You might want to post what magnifications (or eyepiece focal lengths) you have used for the globulars so far.  What diagonal are you using and which Mak is this?  Have you done a basic star test and collimation check just to make things are working properly?  It is not uncommon for a new scope to require collimation after shipping...yes, even a Mak; been there, done that.  RACI diagonals introduce some optical issues as well that show up at higher magnifications.

 

Imaging questions are for another forum that you can check as described in the forum description.

 

As for the visual side of it, I just did a quick check in my suburban back yard (somewhat larger city) with the full Moon rising.  I was using a 72ED refractor in windy conditions.  I stayed at low power, 86x because of the lousy seeing.  Both M13 and M22 partially resolved this way, despite the influence of the Moon and my Bortle 5/6 transition skies.  They still look decent like this, but are certainly not bright or contrasty as they are in dark sky where they better resolve.   A 102mm Mak has slightly less effective light gathering than a 90mm refractor, but because of the large central obstruction the Mak might show stars closer to limit of an 80mm ED/APO refractor, or a little better than that.

 

It is possible that your specific conditions and the Moon are causing much of the trouble.  However, it would be a good idea to do some basic star testing and a collimation check, just to verify that the shape of the diffraction pattern is uniform in the center of the field.  Polaris should be handy for this.  Collimation should not be hard to adjust, and makes a world of difference to a Mak or SCT.

 

What sort of detail have you seen on the planets, particularly Jupiter?  They are rather far south this year, and you are far enough north that the images will suffer, but what you are seeing can give us an idea of whether the scope is performing as expected.


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#8 bjulihn

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Posted 05 August 2020 - 01:07 AM

Hi There;

 

So, you are experiencing what most of us have experienced early on in this hobby. It is not as easy as it looks! First rule of thumb, the problem with most things is not so much that they are small but that they are faint. Planets and Planetary Nebula are indeed small. But most DSO's are quite a bit bigger. There is a reason people call telescopes "Light buckets". The pupil of your eye is 5 to 7 mm when fully dark adapted. Your telescope is 104mm. That means it is catching many times the light your naked eye can catch. When you double the aperture, the light captured increases by the square, so 4X the light.

 

Now magnification spreads out that light. So increasing magnification makes things both dimmer and fuzzier. Many objects are clearest and brightest at lower magnifications. I had an Obsession 18" telescope. It had massive light gathering capability but I rarely observed much above 80X. I don't know what you have for eyepieces but you do need at least a low, a medium, and a higher power eyepiece.

 

A CCD, CMOS, or digital camera is also a "light bucket". But instead of increasing the aperture to catch more light and direct it to your eye, it increases both the sensitivity of the sensor and the time over which the light is captured. A Mallincam video camera could work to increase what you can see, but if you want to go to photography, you are going to need a much better mount.


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#9 Sketcher

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Posted 05 August 2020 - 01:09 AM

In general, for observing deep-sky objects:

 

Observe them only when the sun is at least 18 degrees below your horizon (between evening and morning twilight); and only when the moon is below your horizon.

 

Then there's dark adaptation for the eye.  This takes in the neighborhood of 30 minutes without the eye seeing (being exposed to) any lights that appear to be brighter than the stars one sees in the telescope's eyepiece.  Catch one glimpse of a streetlight, or a car's headlights and the dark adaptation process pretty much has to start over again.

 

The use of "averted vision" is usually of critical importance.  If you're unfamiliar with the term, look it up and learn how to use it.  The use of averted vision can make a huge difference in what can be seen.

 

Try to focus your attention on those DSOs that are high in your sky or near your south meridian.  You want to minimize the column of atmosphere you're looking through.

 

M22 and M13 may have appeared "faint" in your telescope; but under a sky that is free from light pollution, moonlight, etc. both are visible to the naked eye.  So yes, light pollution can have a very significant effect on the visibility of deep-sky objects.

 

The good news is that some deep-sky  objects are far easier to see and far more spectacular than others.  M13 and M22 are not open clusters, they're globular clusters.  In general, the stars in open clusters will be easier to see with a 4-inch telescope than the stars in globular clusters.  So on your next dark, moonless night, after twilight has ended, try for some of the Messier open clusters.

 

The planetary nebulae, M57 and M27 should also be worth looking at.

 

In all cases, experiment with different magnifications.  Some objects are better at low magnifications.  Others are better at high magnifications.  Experimentation while observing is essential.

 

While all deep-sky objects will be better under a darker sky; many can be seen under your sky conditions; and some will be quite beautiful.

 

Your telescope is quite capable when it comes to the Messier objects.  The Messier Album by Mallas and Kreimer and The Messier Objects by O'Meara both contain observing notes and sketches of the Messier objects based on observations made with 4-inch telescopes.  Your views will be a bit compromised due to light-pollution.  But by paying attention to the various suggestions already mentioned, you'll still be able to see quite a bit -- from your location -- with your telescope.

 

One other thing of importance is observer experience.  As your experience grows, you'll be able to see more and more with the telescope you already have.  Sometimes one person with a "small" telescope is able to see more than another is able to see with a considerably larger telescope.

 

Hopefully, some night you'll be able to get away from the city lights and enjoy some of the same objects under more favorable conditions.  Darker skies can make for a small difference with some objects and a much larger difference with other objects.


Edited by Sketcher, 05 August 2020 - 01:13 AM.

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#10 MikeTelescope

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Posted 05 August 2020 - 01:58 AM

What eyepiece focal length were you using?  That 102mm Mak probably has a focal ratio of f/13.  If you are using an eyepiece focal length of much less than 10mm, expect dim views of DSOs.  Rule of thumb is minimum about 7mm, but in many cases this will be pushing it.  If you have something in the 13mm range, use it.  That will be enough magnification to start with.  If the views at 13mm don't look OK, something is wrong.  

 

Maks like that take a long time to reach ambient temperature.  If you didn't let it acclimate for at least 30 mins after taking it outside, and then start pushing magnification, expect images not to resolve well.  An hour would be better. 

 

Unless you dropped the scope, it should be fairly well collimated from the factory.  But a simple star test on Polaris should be able to check this.  Defocus on Polaris and check for a concentric diffraction pattern that is roughly the same on either side of focus.  

 

For globular clusters, don't expect to see many individual stars with 102mm of aperture.  Maybe some on the outer fringe, but the rest should be a tight fuzzy ball.  


Edited by MikeTelescope, 05 August 2020 - 02:05 AM.


#11 Jon Isaacs

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Posted 05 August 2020 - 04:01 AM

JR:

 

Hello and welcome.gif to Cloudy Nights.

 

You have gotten lots of good stuff so far.

 

I just want to encourage you to stick with it, hang in there. 

 

Observing, star gazing is are a set of skills one develops.  The more you do it, the better you get at it, the more you see.  It's really a life time of learning, experimenting and understanding.  

 

M13 and M22 are both globular clusters so you will only partially resolve them.  Open clusters are more easily seen and resolved.  M11 would be a good object though it's quite faint.  M6 and M7 are two amazing clusters but quite low on the horizon from Madison.  Two good DSOs are the nebulae M27, the Dumbbell and M57 the ring nebula.  

 

A 102 mm Mak is a good instrument for binary stars.  These can take higher magnifications so more eyepieces may be needed.  Alberio is a must see.  Epsilon Lyrae, the double-double, is a pair of stars that are each double stars. They might take a 100x or more to separate and a stable atmosphere, "good seeing."

 

The reality of amateur astronomy is that most objects are small and faint.  A bigger scope helps one see more but generally what happens is you end up just looking at even smaller, fainter objects.

 

Jon


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#12 Xarast

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Posted 05 August 2020 - 06:33 AM

Hi All. I am new and this is my first post.

I found this thread very useful.

 

I am trying to understand whether I could also improve my experience with DSOs.

My reflector telescope is 130mm aperture and 650mm focal length. I predominantly use 25mm and 10mm eyepieces.

I am not sure how good these eyepieces are as I paid around USD15/25 for each.

I can observe planets such as Jupiter in sufficient details, but when I turn to, say, the Andromeda galaxy all I see is an extremely faint nebula like splodge. Even with clear sky and reasonably low light pollution (I live in the countryside far from light sources).

As I am not planning to upgrade the scope just yet, I was wondering whether investing in a better eyepiece would be wise instead?

 

Thank you!


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#13 Voyager 3

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Posted 05 August 2020 - 08:46 AM

I will say that for DSOs your experience comes next to light pollution! You just found Andromeda right? OBSERVE it rather than VIEWING it . Wait till your eyes get dark adapted (usually 30 mins) and use averted vision when observing it . You will get to know after , gaining some experience that you can see more details than before . OBSERVE OBSERVE OBSERVE ... And gd luck on your next hunt 👍🏻

#14 rhetfield

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Posted 05 August 2020 - 09:05 AM

Keep in mind M13 and M22 are globular clusters, NOT open clusters. So they need magnification to resolve them. If you have dark skies and use 150-200x magnification, you are in for a treat.

In city skies, or full moon skies, they disappoint.

Scott

In my 5", it takes both dark skies and good viewing to see detail in the globulars.  They are relatively dim and I would not try to go much above 100x mag in your scope.  Much of what is seen in the picture grid above is the loss of resolution that smaller scopes see when they go too high in magnification.


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#15 Waddensky

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Posted 05 August 2020 - 09:07 AM

but when I turn to, say, the Andromeda galaxy all I see is an extremely faint nebula like splodge.

May I ask what you expected to see? The Andromeda Galaxy will always be a reasonably bright but featureless smudge in smaller apertures. But a smudge at a distance of 2.5 million light-years!

 

I agree with Voyager 3, learning to observe will improve your skills tremendously. You will become much better in discerning tiny contrasts and small details if you give yourself the time to build up experience.

 

A better eyepiece will give you more observing comfort, better eye relief, higher contrast, a wider field of view and such but doesn't suddenly turn a smudge into a photographic picture wink.gif.

 

Oh, and welcome! smile.gif


Edited by Waddensky, 05 August 2020 - 09:15 AM.

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#16 Xarast

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Posted 05 August 2020 - 09:11 AM

I will say that for DSOs your experience comes next to light pollution! You just found Andromeda right? OBSERVE it rather than VIEWING it . Wait till your eyes get dark adapted (usually 30 mins) and use averted vision when observing it . You will get to know after , gaining some experience that you can see more details than before . OBSERVE OBSERVE OBSERVE ... And gd luck on your next hunt

Thanks. That's really wise advice.



#17 rhetfield

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Posted 05 August 2020 - 09:12 AM

Hi All. I am new and this is my first post.

I found this thread very useful.

 

I am trying to understand whether I could also improve my experience with DSOs.

My reflector telescope is 130mm aperture and 650mm focal length. I predominantly use 25mm and 10mm eyepieces.

I am not sure how good these eyepieces are as I paid around USD15/25 for each.

I can observe planets such as Jupiter in sufficient details, but when I turn to, say, the Andromeda galaxy all I see is an extremely faint nebula like splodge. Even with clear sky and reasonably low light pollution (I live in the countryside far from light sources).

As I am not planning to upgrade the scope just yet, I was wondering whether investing in a better eyepiece would be wise instead?

 

Thank you!

Even in dark skies, galaxies tend toward being relatively dim.  The globulars are much easier to work with.  If you get into bortle 1 or 2 skies, you can see a bit more detail in the galaxies.  They, along with nebulas are very much hit or miss.  I have the same experience with the galaxies using the same scope.  Even when I can see them with the binos.  Pretty much need bigger aperture to do much better.  Different eyepieces will make only a very subtle difference.  Different eyepieces would be more noticable on the planets and open clusters/stars.  Fine tuning your star collimation will make as much a difference as different eyepieces. 



#18 Xarast

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Posted 05 August 2020 - 09:17 AM

May I ask what you expected to see? The Andromeda Galaxy will always be a reasonably bright but featureless smudge in smaller apertures. But a smudge at a distance of 2.5 million light-years!

 

I agree with Voyager 3, learning to observe will improve your skills tremendously. You will become much better in discerning tiny contrasts and small details if you give yourself the time to build up experience.

 

A better eyepiece will give you more observing comfort, better eye relief, higher contrast, a wider field of view and such but doesn't suddenly turn a smudge into a photographic picture wink.gif.

I guess I was just hoping for a 'brighter' experience with Andromeda. I am not expecting to see much details but probably more light. To me it looked like a very faint cloud AND with no detail whatsoever.

If that is what I should be seeing, even with better eyepieces, then I will just re-assess my expectations.

I just want to make sure I am not doing anything wrong.

Thanks!


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#19 rhetfield

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Posted 05 August 2020 - 09:22 AM

One that is worth finding is M11.  That one is a small, but dense open cluster.  It looks nice at around 100x mag or so.


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#20 Xarast

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Posted 05 August 2020 - 09:23 AM

Even in dark skies, galaxies tend toward being relatively dim.  The globulars are much easier to work with.  If you get into bortle 1 or 2 skies, you can see a bit more detail in the galaxies.  They, along with nebulas are very much hit or miss.  I have the same experience with the galaxies using the same scope.  Even when I can see them with the binos.  Pretty much need bigger aperture to do much better.  Different eyepieces will make only a very subtle difference.  Different eyepieces would be more noticable on the planets and open clusters/stars.  Fine tuning your star collimation will make as much a difference as different eyepieces. 

Thanks, that's very good to know!

I was about to spend a couple of hundreds on a new eyepiece. I might think about getting a wider scope instead. Hopefully it will go on my mount.

Thinking about it, I remember having a decent view of the Orion nebula last winter, which is allegedly higher magnitude than Andromeda (?)

I will have another go with Andromeda.



#21 Waddensky

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Posted 05 August 2020 - 09:24 AM

I guess I was just hoping for a 'brighter' experience with Andromeda. I am not expecting to see much details but probably more light. To me it looked like a very faint cloud AND with no detail whatsoever.

If that is what I should be seeing, even with better eyepieces, then I will just re-assess my expectations.

I just want to make sure I am not doing anything wrong.

Thanks!

That sounds about right, you're not doing anything wrong as far as I can tell (although I wouldn't describe M31 as very faint from the countryside, it's a naked object if you know where to look). Make sure you don't use too much magnification, your 25 mm eyepiece is probably best. M32 will look like a fuzzy star at that magnification next to M31, M110 is also nearby but a bit more challenging than its brighter neighbours. Good luck!


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#22 Migwan

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Posted 05 August 2020 - 09:27 AM

Hi All. I am new and this is my first post.

I found this thread very useful.

 

I am trying to understand whether I could also improve my experience with DSOs.

My reflector telescope is 130mm aperture and 650mm focal length. I predominantly use 25mm and 10mm eyepieces.

I am not sure how good these eyepieces are as I paid around USD15/25 for each.

I can observe planets such as Jupiter in sufficient details, but when I turn to, say, the Andromeda galaxy all I see is an extremely faint nebula like splodge. Even with clear sky and reasonably low light pollution (I live in the countryside far from light sources).

As I am not planning to upgrade the scope just yet, I was wondering whether investing in a better eyepiece would be wise instead?

 

Thank you!

M31 is quite diffuse and 3° across.  Its a difficult target for even bigger scopes.  Your 25mm (if a Plossl) gives you a 2° field of view.  So on a good transparent dark night (no moon or light pollution), see if you can observe the extent of M31 by slowly moving the scope back and forth and up and down.  If you manage to see the extent of M31, you have done well Grasshopper. 

 

Assuming you are limited to a 1.25" eyepiece, your maximum field of view would limited to around 2.5° with a 32mm Plossl, a 24mm68° or similar.  Considering that, you might not want jump into another EP specifically for M31.   However, there are other targets that would benefit from that, but why hurry.  

 

jd


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#23 MalVeauX

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Posted 05 August 2020 - 09:28 AM

Hrm,

 

Well, with a 4" aperture you're really not going to see nebula, galaxies, etc, for the most part except for a few really bright ones, more than just seeing them as a slightly brighter smudge than surrounding darker sky; and that's from a very dark sky location, out of light pollution to get the best surface brightness on your subjects. These small apertures are much better suited to solar system visual (planets, moon, sun) and things like clusters, globs, doubles, etc, things that are basically stars and not simply collections of lots of stars & dust. It takes a lot of aperture to see detail in a galaxy and nebula visually under light pollution. I say this in the context of someone having less experience viewing DSO in the first place, compared to someone who's very experienced and will know the location and spot the DSO. But they're not magically seeing more than you are if both are dark adapted, they just know more about what they are seeing (which a new observer may miss or not notice as signfiicant).

 

Very best,


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#24 Xarast

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Posted 05 August 2020 - 09:48 AM

Thank you all for your input waytogo.gif



#25 Sketcher

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Posted 05 August 2020 - 11:47 AM

I am trying to understand whether I could also improve my experience with DSOs.

My reflector telescope is 130mm aperture and 650mm focal length. I predominantly use 25mm and 10mm eyepieces.

I am not sure how good these eyepieces are as I paid around USD15/25 for each.

I can observe planets such as Jupiter in sufficient details, but when I turn to, say, the Andromeda galaxy all I see is an extremely faint nebula like splodge. Even with clear sky and reasonably low light pollution (I live in the countryside far from light sources).

As I am not planning to upgrade the scope just yet, I was wondering whether investing in a better eyepiece would be wise instead?

In my opinion, the two best ways of improving one's experience with DSOs are:

 

1.  Observing from a darker sky -- yes, it really can make a huge difference!

2.  Increasing one's experience in observing DSOs -- this also can make a huge difference!

 

Combine 1 and 2 above and your views become "unworldly" contrasted to that with which most are accustomed to seeing.

 

Different eyepieces have different advantages, but mostly, what one gets by paying more for an eyepiece are:

 

 a.  wider apparent fields of view than one can get with the less expensive eyepieces

 b.  sharper views near the edge of one's field of view

 c.  more comfortable to use -- better eye-relief

 

That which you see near the center of the field of view will be pretty much the same (assuming the magnification is the same) regardless of the price and design of the eyepiece one uses.

 

Yet, it's amazing how many people go out of their way to purchase those expensive, wide-field eyepieces in the hope of seeing everything better.

 

* * * * * * * * * * * * * * * * * * 

Now for the Andromeda Galaxy:

 

From a light-polluted location (even with relatively mild light-pollution) the outer regions of M31 will be too faint to see -- pretty much regardless of the aperture of one's telescope.  Aperture cannot change the contrast of those outer regions with the (brighter) background sky.  So forget about getting much of an "Andromeda advantage" by purchasing a bigger telescope.

 

Similarly, an eyepiece that provides a wider true field of view may also lead to disappointment -- because chances are, the eyepieces you're currently using already provide you with a wide enough true field to enclose the entire region of M31 that's bright enough for you to see, under your sky conditions, etc.

 

To translate all of this into an image (or more precisely, a sketch) I'm going to do something that I usually try to avoid on the beginner's forum.  I avoid it in order to not give people unrealistic expectations.  After all, the following sketch was made under some of the darkest skies available in the continental U.S. by an observer who's lived and observed under such a sky for a number of decades.

 

That being said, the eyepiece used was a relatively inexpensive, Orion 20mm Expanse.  The true field of view encompassed by the sketch is about 3.3 degrees.  Be sure to take note of the aperture used!  For there-in lies the crux of the matter:

 

M31 32 110  1 inch aperture 5 Dec 2018 20x Sketcher   text 1
 
Notice also that three galaxies appear in the above sketch.
 
One further note:  Sketches of deep-sky objects will often transform details that were "just" visible in the eyepiece into details that can be quickly noticed by just a brief glance at the sketch.  So don't assume the entire majestic extent of M31, as seen in the above sketch, was as obvious in the eyepiece as it appears in the sketch.  That would be a mistake.  But with experience, seeing faint details become easier and easier and easier and more and more obvious to an experienced eye.behind an eyepiece.



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