Problems with the andromeda galaxy

[Adamchiv]

Yeah finding the red dot is similar to finding your car keys, or finding pluto

[D4N]

56 minutes ago, Adamchiv said:

I agree the widefield view looks perfect and I do wish I had a wider field, I have been contemplating getting the skywatcher 80ed on a heq 5 mount, but thought more aperture was better which is why I was also considering the big dobsonians. Im a teeny bit confused about these circles on this image, the reason being I can understand that a 40mm eyepiece is going to give you a wider field, but how much narrower would that 40mm be on a 10-12" newtonion reflector? Im kind of confused about whether I should go for the quality of a refractor, or the good value for money large aperture of a reflector

It's not a question of quality, you can have poor quality refractors and good quality reflectors.

Typically scopes with larger apertures will have longer focal lengths (they get very expensive to make otherwise).  The longer focal length will provide more magnification but at the cost of a reduced field of view.

You can have extremes like scopes with over 2m focal length that will only show a very tiny patch of sky no matter what eyepiece you use or the other way around you can get very small scopes that give a wide field of view but will be unable to reach high magnifications.

[Adamchiv]

52 minutes ago, D4N said:

It's not a question of quality, you can have poor quality refractors and good quality reflectors.

Typically scopes with larger apertures will have longer focal lengths (they get very expensive to make otherwise).  The longer focal length will provide more magnification but at the cost of a reduced field of view.

You can have extremes like scopes with over 2m focal length that will only show a very tiny patch of sky no matter what eyepiece you use or the other way around you can get very small scopes that give a wide field of view but will be unable to reach high magnifications.

Yeah totally, but whats suprising me is that usually when people say they want to observe deep sky targets, large aperture dobsonian reflectors seem to be mentioned more than any other. Ive also read a lot of people saying large aperture more light gathering the better. Thats why im a little confused. Now im certainly thinking about a refractor as I dont want to only see a small part of nebulae and clusters etc, but then why do people use/crave massive newtonians for that type of thing? Is it the fact that very deep sky targets will be small in the eyepiece so the long focal length plus the light gathering power is perfect for them?

[rockystar]

maybe a simple way to look at it is that a large dob will show you fainter things and a wide field frac will show you bigger things - on a simplistic level.

other than Andromeda, which as you've seen can look huge under the right conditions - most galaxies are small and faint. Whereas some of the emission nebulae and super nova remnants are quite large.

 

[Adamchiv]

17 minutes ago, rockystar said:

maybe a simple way to look at it is that a large dob will show you fainter things and a wide field frac will show you bigger things - on a simplistic level.

other than Andromeda, which as you've seen can look huge under the right conditions - most galaxies are small and faint. Whereas some of the emission nebulae and super nova remnants are quite large.

 

That makes total sense and is what Ive managed to grasp finally lol. It does make it hard for me to decide what to go for when I upgrade now but thats not for a while yet. Going back to andromeda, I live a mile from heaton park, am I being a bit optimistic trying to see the andromeda galaxy? 

[rockystar]

7 minutes ago, Adamchiv said:

That makes total sense and is what Ive managed to grasp finally lol. It does make it hard for me to decide what to go for when I upgrade now but thats not for a while yet. Going back to andromeda, I live a mile from heaton park, am I being a bit optimistic trying to see the andromeda galaxy? 

that's why I've decide that I'll eventually get both

I think you should be able to see it, but it will only be the bright core, I've seen it in my binocular from there. You'll know it once you find it.

if it's clear next Thursday (8th Dec), I'll come down to the meeting, come find me, I'll give you a hand. (can't make this week, other plans and the weather is looking like clouds anyway)

[D4N]

Andromeda can be seen naked eye from a reasonably dark location, it can be seen with binoculars even from fairly light polluted areas but it really shines at dark sites where you start to see the spiral structure.

[Adamchiv]

 

2 minutes ago, rockystar said:

that's why I've decide that I'll eventually get both

I think you should be able to see it, but it will only be the bright core, I've seen it in my binocular from there. You'll know it once you find it.

if it's clear next Thursday (8th Dec), I'll come down to the meeting, come find me, I'll give you a hand. (can't make this week, other plans and the weather is looking like clouds anyway)

Thanks a lot, ok I'll pm you if you like, would be good to get some one on one help. I always like to learn

[Peter Drew]

If you can get over to us at the Astronomy Centre, on a clear night we can show you what the Andromeda galaxy looks like with the naked eye, binoculars or through wide field refractors and large and small Dobsonians. 

[Stu]

Adam, the tricky concept to get your head around is that a big dob can never make give a higher surface brightness than you observe with the naked eye. What they are able to do is maintain that surface brightness at larger image scales. Your eye is sensitive to brightness, contrast but also image scale i.e. Larger image scale gives higher perceived contrast. They really come into their own when observing smaller fainter objects under a dark sky such as galaxies. You are able to increase the size whilst keeping the brightness and the results can be amazing.

As a comparison on M31, with a widefield refractor under a dark sky you would be able to take in the whole extent of the Galaxy and start to see its spiral arms. They are very subtle but the detail is there.
In a big dob (16 to 20" say) you would be able to see the finer detail and perhaps observe some of the brighter globular clusters around it.
Another major benefit of aperture is resolution. Stick a big dob on M13 and you will fall off your observing chair!

There aren't that many large objects up there, so most of the time it is not so much of an issue, but personally I really enjoy scanning the Milky Way with a 3, 4 or even 5 degree afov. I will dig out my Genesis report from Dorset and add it to this post.

With some of these larger objects such as the North America Nebula or Rosette, if you don't have sufficient afov you can end up looking through the object, i.e. The fov is filled with similar surface brightness and you cannot detect any contrast because the edges are outside the fov. The image posted shows a 12" f5.3 scope with three eyepieces, a 40mm 2" TMB Paragon, a 24mm 68 degree Panoptic and a 12.5mm BGO.

As you can see, with the BGO it is doubtful you would detect the Nebula. With the Panoptic you might catch an edge and be able to trace around the object, but with the 40mm you would see the object in context and your eye would pick up the contrast at the edges.

For reference the last image shows the fov of the 40mm when used in a Televue NP101, a scope with a lovely short focal length but which maintains a flat field.

Enough rambling, hope that helps a little.

Stu

Observing reports below

https://stargazerslounge.com/topic/223288-genesis-under-dorset-dark-skies/#comment-2402055

https://stargazerslounge.com/topic/223732-dorset-sagittarius-adventures/#comment-2406891

 

[Adamchiv]

2 hours ago, Peter Drew said:

If you can get over to us at the Astronomy Centre, on a clear night we can show you what the Andromeda galaxy looks like with the naked eye, binoculars or through wide field refractors and large and small Dobsonians. 

I mentioned this possibility to my girlfriend the other night and she said we should go, id have to rent a car though but im sure it would be well worth it. Thanks peter

[Peter Drew]

3 minutes ago, Adamchiv said:

I mentioned this possibility to my girlfriend the other night and she said we should go, id have to rent a car though but im sure it would be well worth it. Thanks peter

You will be welcome any Saturday evening. Keep an eye on the weather though if you're having to rent a car, it must be clear to see anything.  

[Adamchiv]

Thankyou stu that was a very informative post. I liked your report too I bet that was a superb trip! 

I think having learned all this I have to decide what it is I most want to see. Faint galaxies are what really interest me the most and always have done. 

So a big dobs would be more suitable I think to take advantage of darker skies looking for those further away galaxies. But then part of me wants to get into very basic imaging, and having a skywatcher 80 on a heq5 mount would give me a bit more leverage than having a dobs and then having to spend more money. 

So I will have to wait and see just how much I want to image, because right now I get such a high out of observing that I dont want it to change.

Something for me to think on anyway, thanks again

[Adamchiv]

I will have to keep an eye on the weather peter, thats whats gona ruin it but it has been pretty good so far this week

[Dave In Vermont]

My signature below shows my way of covering the bases of high-to-low magnification, wide-field - low-power, narrow-field - high-power, medium-power & FOV refractor, and going way-deep with high-power-possible, telescope collection. The 150mm F/12 Maksutov being my last acquisition for solar-system objects and the Moon.

It didn't happen overnight. So don't race yourself to the Poor-House. You'll get there, slowly, as your interests shift and zero-in.

Dave

[Adamchiv]

10 minutes ago, Dave In Vermont said:

My signature below shows my way of covering the bases of high-to-low magnification, wide-field - low-power, narrow-field - high-power, medium-power & FOV refractor, and going way-deep with high-power-possible, telescope collection. The 150mm F/12 Maksutov being my last acquisition for solar-system objects and the Moon.

It didn't happen overnight. Sodon't race yourself to the Poor-House. You'll get there, slowly, as your interests shift and zero-in.

Dave

Thanks dave thats good advice

[valleyman]

try finding it with Binos first. That will give you a good idea where it is. Then when using the finder scope keep both eyes open. Use one eye on the location and the 2nd eye on the finder.Bring the two views together and you should find it.

 

Bit like using a mechanical range finder

[Stu]

On 29/11/2016 at 15:49, Adamchiv said:

Thankyou stu that was a very informative post. I liked your report too I bet that was a superb trip! 

I think having learned all this I have to decide what it is I most want to see. Faint galaxies are what really interest me the most and always have done. 

So a big dobs would be more suitable I think to take advantage of darker skies looking for those further away galaxies. But then part of me wants to get into very basic imaging, and having a skywatcher 80 on a heq5 mount would give me a bit more leverage than having a dobs and then having to spend more money. 

So I will have to wait and see just how much I want to image, because right now I get such a high out of observing that I dont want it to change.

Something for me to think on anyway, thanks again

No problem Adam. I would agree that for faint galaxies, which are often small, a big dob is what you need. The only qualification I would add to that is the ability to get it to dark skies. If the galaxies are drowned out by LP then it doesn't matter how big your scope, you won't see the galaxies!

[Adamchiv]

16 minutes ago, valleyman said:

try finding it with Binos first. That will give you a good idea where it is. Then when using the finder scope keep both eyes open. Use one eye on the location and the 2nd eye on the finder.Bring the two views together and you should find it.

 

Bit like using a mechanical range finder

Thats a good idea, I do that with the finder scope but if my binos will see through the lp and locate it that will really help. thanks

[Adamchiv]

1 minute ago, Stu said:

No problem Adam. I would agree that for faint galaxies, which are often small, a big dob is what you need. The only qualification I would add to that is the ability to get it to dark skies. If the galaxies are drowned out by LP then it doesn't matter how big your scope, you won't see the galaxies!

Thats very true stu, that is my aim next year to go to as many dark sites as possible, otherwise spending 500+ pounds or whatever it may be will not be worth it

[hobsey]

On Tuesday, November 29, 2016 at 03:14, MBJ said:

Look for the great square of pegasus.....a near perfect large square of four stars tilted over.....the far left star which is alpheratz.....count 2 stars in a line to the left of alpheratz and then 2 stars up and that is where andromeda is.

Yep, I use this method too.

It's fool proof, I find Andromeda every time.

[Adamchiv]

Heres a realistic rendition of what I could see, as you can see only the first pointer star next to mirach is visable (barely) which for some reason I mistook for andromeda itself (bad day at the office). the second pointer star wasnt visable at all which makes it hard for me to know where to point. I would have to guess it pretty much

[Stu]

On 30/11/2016 at 19:40, Adamchiv said:

Heres a realistic rendition of what I could see, as you can see only the first pointer star next to mirach is visable (barely) which for some reason I mistook for andromeda itself (bad day at the office). the second pointer star wasnt visable at all which makes it hard for me to know where to point. I would have to guess it pretty much

That does look a bit tough. Get yourself somewhere darker. Remember the surface brightness of M31 is not dissimilar to the Milky Way, so if you are getting a good clear view of the MW, the Andromeda Galaxy should be a naked eye object just about.

[Adamchiv]

12 hours ago, Stu said:

That does look a bit tough. Get yourself somewhere darker. Remember the surface brightness of M31 is not dissimilar to the Milky Way, so if you are getting a good clear view of the MW, the Andromeda Galaxy should be a naked eye object just about.

I think my location is the biggest detriment to my observing by a long way. With these skys I really dont believe there is much after pleiades and the planets

[John]

17 minutes ago, Adamchiv said:

....... With these skys I really dont believe there is much after pleiades and the planets

Double stars, clusters, planetary nebulae ?