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Differences between 10 and 12"

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#26 Jon Isaacs

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Posted 26 July 2021 - 03:45 PM

You're certainly entitled to your opinion. My experience is that they are more different, by a wide margin,  than they are similar...

 

We're both entitled to our opinions. 

 

It's a half magnitude and 25% in resolution.  In my book, that's not a wide margin. A wide has to be at least a full magnitude. From the same location,  on a good night the 10 inch will show as much as the 12.5 inch on a mediocre night.

 

Jon


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#27 RLK1

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Posted 26 July 2021 - 03:49 PM

It's a half magnitude and 25% in resolution.  In my book, that's not a wide margin. A wide has to be at least a full magnitude.

 

Jon

I knew I would get the numbers game. That's why I emphasized image scale...



#28 cuzimthedad

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Posted 26 July 2021 - 03:55 PM

Ok folks time to get back on topic. Take the arguing to the PM room please.


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#29 turtle86

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Posted 26 July 2021 - 04:49 PM

Funny thing. The older gentleman who sold me 12" it's retiring from this hobby. Also his friend probably the same age it's retiring From this hobby too and he have 16" lightbridge. Now we are trying to Negotiate I'm buying it from him the 16"

 

Let us know if you wind up getting the 16".  That would definitely be a significant jump in aperture from the 10".


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#30 Woj2007

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Posted 26 July 2021 - 05:37 PM

Comparing my 10" f/4.8 and 12" f/5.3  I'd say that optically both are delivering great views.

The 12" usually has a slight edge on details when it comes to globulars like M3, Jupiter or Saturn. With the washed out skies, viewing nebulae indicates a difference in light gathering, but not a dramatic one.

Eventually, 10" solid tube is my city scope, and 12" truss is taken to dark skies to impress me with faint cotton candies smile.gif

If I only could have one of them, that would be the 12", provided premium optics and coatings ceteris paribus.


Edited by Woj2007, 26 July 2021 - 05:48 PM.

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#31 turtle86

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Posted 26 July 2021 - 05:44 PM

Comparing my 10" f/4.8 and 12" f/5.3  I'd say that optically both are delivering great views.

The 12" usually has a slight edge on details when it comes to globulars like M3, Jupiter or Saturn. With the washed out skies, viewing nebulae indicates a difference in light gatherimg, but not a dramatic one.

Eventually, 10" solid tube is my city scope, and 12" truss is taken to dark skies to impress me with faint cotton candies smile.gif

If I only could have one of them, that would be the 12", provided that optics and coatings were premium. 

 

That's exactly what I do. I use my 10" tube Dob in my light-polluted backyard, and take my 12.5" Dob to dark skies where it can perform much better.


Edited by turtle86, 26 July 2021 - 05:59 PM.

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#32 Pitu

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Posted 26 July 2021 - 09:18 PM

Let us know if you wind up getting the 16".  That would definitely be a significant jump in aperture from the 10".

Hope I can get and I think it will by good but in my 50s look i have to join the gym to put some muscles


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#33 Keith Rivich

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Posted 26 July 2021 - 10:28 PM

Hope I can get and I think it will by good but in my 50s look i have to join the gym to put some muscles

Its funny you mention this as I do do exercises in the gym that mimic the lifting I need to work with my 25" smile.gif


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#34 sopticals

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Posted 27 July 2021 - 12:34 AM

Its funny you mention this as I do do exercises in the gym that mimic the lifting I need to work with my 25" smile.gif

Don't go to the gym as such, but do try to keep strength up by doing daily press ups and pull ups to keep my 76 1/2 year old frame up to the task of moving my large scopes.

 

Stephen.(45deg.S.)


Edited by sopticals, 27 July 2021 - 12:35 AM.

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#35 Illinois

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Posted 27 July 2021 - 06:16 AM

Let us know if you wind up getting the 16".  That would definitely be a significant jump in aperture from the 10".

Jump to 16 inch from 10 inch is big difference but 16 inch is BIG and HEAVY! You can see picture of me and my 16 inch dobsonian! That’s why I use homemade ball bearing base that I can move it out and in of my garage. It’s great in Wisconsin that is much darker sky for deep sky objects.  I enjoy my refractor as grab and go also 180mm MakCass for planetary at my home. 


Edited by Illinois, 27 July 2021 - 06:18 AM.

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#36 turtle86

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Posted 27 July 2021 - 07:14 AM

Hope I can get and I think it will by good but in my 50s look i have to join the gym to put some muscles

 

It definitely helps to be in decent shape when handling these bigger scopes.  I actually got my 12.5" Dob *after* I already had my 18", for those times when my lower back strongly objected to me handling the 18".  lol.gif  


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#37 dragonstar4565

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Posted 27 July 2021 - 12:36 PM

Hello there, this is how I see it: The difference between a 10", and 12" scope is small and really is just an incremental jump in brightness and resolution. This small difference is not enough to outweigh the other hassles of the bigger scope.

 

A 12" has a mere 20% better resolving power, and 44% or 0.4 magnitudes more penetration then a 10" scope, which is not a lot at all. At the very limit of both scopes, this small increase would be very subtle.

 

For example: If you were looking at the very faint Perseus cluster of galaxies, you would see that the fainter members would be at the edge of detection for the 10" scope, and just visible with direct averted vision with the 12" under the same skies.

 

This is the kind of change you can expect, for other very faint objects, that are at the limit of both scopes, under the same skies, which is quit minuscule. This type of small increase in brightness is so subtle, that I would be happy with either scope.

 

The 10" scope operating at 100x, will be just as bright as a 12" scope operating at 120x, and the image scale is only just very slightly larger for the 12" at the same power for the 10". This is somewhat noticeable, but it is a small change.

 

The contrast remains unchanged, and the eye does does not perceive this increase in brightness in a linear way, but rather logarithmic ally, so the increase in brightness and resolution is small to the eye. The 10" scope, and 12" scope are more similar then different.

 

In a nutshell there is nothing a good 12" scope can see, that a good 10" can't see under similar skies, the 12" scope will just be a hair brighter at the same power, but this difference is not enough, to discount a 10" scope over a 12" scope...clear skies...smile.gif     


Edited by dragonstar4565, 27 July 2021 - 01:39 PM.

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#38 Redbetter

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Posted 27 July 2021 - 01:24 PM

 

In a nutshell there is nothing a good 12" scope can see, that a good 10" can't see under similar skies, the 12" scope will just be a hair brighter at the same power, but this difference is not enough, to discount a 10" scope over a 12" scope...clear skies...smile.gif     

That is just not accurate.  In similar skies, the extra light grasp means the 12" can go about 0.4 magnitude deeper.  A full magnitude will reveal about 3x more galaxies, while .4 magnitude corresponds to about 55% more.  

 

I guarantee you that given equivalent scope quality, I could find things with a 12" that could not be detected in a 10".  It would be easy to do in the Perseus galaxy cluster that you mention, as it has quite a range of galaxy magnitudes--I have seen at least 150 of them with the 20".    It would be rather easy with supernovae as well, since 0.4 magnitude is well within the range of detection or non-detection.  

 

The reality is that when someone says they can use smaller aperture to see anything an incrementally larger aperture will show, they are really saying that they won't push the larger aperture to its limits, but they will push the smaller aperture to its limits.  It is an apples and oranges comparison.


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#39 turtle86

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Posted 27 July 2021 - 01:27 PM

Hello there, this is how I see it: The difference between a 10", and 12" scope is small and really is just an incremental jump in brightness and resolution. This small difference is not enough to outweigh the other hassles of the bigger scope.

 

A 12" has a mere 20% better resolving power, and 44% or .4 magnitudes more penetration then a 10" scope, which is not a lot at all. At the very limit of both scopes, this small increase would be very subtle.

 

For example: If you were looking at the very faint Perseus cluster of galaxies, you would see that the fainter members would be at the edge of detection for the 10" scope, and just visible with direct averted vision with the 12" under the same skies.

 

This is the kind of change you can expect, for other very faint objects, that are at the limit of both scopes, under the same skies, which is quit minuscule. This type of small increase in brightness is so subtle, that I would be happy with either scope.

 

The 10" scope operating at 100x, will be just as bright as a 12" scope operating at 120x, and the image scale is only just very slightly larger for the 12" at the same power for the 10". This is somewhat noticeable, but it is a small change.

 

The contrast remains unchanged, and the eye does does not perceive this increase in brightness in a linear way, but rather logarithmic ally, so the increase in brightness and resolution is small to the eye. The 10" scope, and 12" scope are more similar then different.

 

In a nutshell there is nothing a good 12" scope can see, that a good 10" can't see under similar skies, the 12" scope will just be a hair brighter at the same power, but this difference is not enough, to discount a 10" scope over a 12" scope...clear skies...smile.gif     

 

Under equal conditions, a 12" does indeed go a little deeper than a 10" as Redbetter points out, but it's up to the individual to decide if the juice is worth the squeeze, since the 12" is going to be a bit heavier, as in the OP's case. For someone who needs to travel to a dark site to escape light pollution, the 10" would be the better choice if that person finds a 12" too bothersome to transport.  The best scope is the one you use, and a 10" under a dark sky will beat a 12" under a light-polluted sky every time.


Edited by turtle86, 27 July 2021 - 01:40 PM.

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#40 Starman1

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Posted 27 July 2021 - 02:23 PM

Let's see:

12" f/5 has an image scale of 2.26'/mm of focal plane

10" f/5 has an image scale of 2.71'/mm of focal plane.

The 10" has a slightly smaller image scale--by around 20%. 

I can see where that might be considered significant.

 

Light grasp has already been discussed.

 

The question is whether, on the really bright objects the OP describes, there would be an appreciable difference, and I don't think there would be.

But, as the objects get fainter, the 12" would come into its own:

--it would be able to use slightly higher magnifications without the object becoming too dim.

--it would pick up fainter objects and see details in objects the 10" won't.

 

On the other hand, the improved resolution of small details in the 12" might be moot if the scope cannot be used at high powers due to the seeing.

 

Personally, I'd rather have a 12" than a 10", but if the OP is confined to the city and only the brightest DSOs, the 10" might be easier to use.

0.4 magnitudes is a paltry amount when you could gain a few magnitudes by taking the scope to a darker sky site.  A 10" at a dark site trumps a 12" in the city.

The secondary mirrors in most newtonian scopes results in a 0.4 magnitude drop at the edge of the field and yet we don't notice the edge of the field is darker.

I'm just sayin'.

 

There is some truth in every post in the thread.  Sometimes the scope choice is a balancing act: Weight vs. Light grasp, Transportability vs. image scale.

I won't upgrade my 12.5" to a 16" because the half magnitude gain is not significant to me.  I want a full magnitude difference (20"), but the 20" scope isn't in the cards for me.

I'll settle for the 12.5" and try to get more time to observe.  It doesn't matter what the scope size is if you aren't using it.


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#41 rgk901

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Posted 27 July 2021 - 05:31 PM

I do not own a 12" but I do own a 5" & 10" and would just like to confirm the importance of a darker sky.

 

At home (B-8/9) the 5" sees m13 just barely as a faint fuzz ball, the 10" sees a faint fuzzball but larger and stars on edge start to resolve a tiny bit.

 

Last family camping trip I just couldn't fit the 10" so took the 5" along and at B-2/3 m13 was better resolved in the 5" than it was in the 10" at home! And that's half the mirror size. Can't wait to bring the 10" to a dark sky but at the same time I enjoyed the 5" very much. Given I am talking about a 5" &10" and still enjoyed the 5" I see no reason to think a 10" & 12" would be anywhere near that great of a disparity and either will definitely offer enjoyable views, I'm sure.

 

Sometimes have to put the calculations aside and enjoy the view :) but I do understand FOMO as I have it too :)



#42 dragonstar4565

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Posted 27 July 2021 - 06:17 PM

Hello again, I have used both apertures extensively, so I've done my homework. 0.4 magnitudes, is the difference between  detecting an object at the limit of detection in the 10", to seeing the object with averted vision with the 12" scope. 

 

Under dark skies, this would be more noticeable, however it is not a big improvement, and even seeing a very faint 15.5v magnitude or slightly fainter star in the 10" would be detectable 50% of the time in the 10", and detectable with the 12" scope 75% of the time when used at the same power, under the same conditions.

 

When you increase the power in both scopes, fainter stars will be easier to see, and a star right at the limit of both scopes like stated above would have a similar effect, although the star being scrutinized will be slightly easier in the 12" scope allowing the observer to detect the star 25% longer then the 10" scope, at any given time.

 

If you really want to brighten up a 15v magnitude star you will need at least a 22" or bigger scope. Even in this aperture the true limit is usually not reached because of seeing conditions, and other factors, such as collimation, although 15v magnitude or fainter is rather routine in this aperture.

 

This is how it works, sense the eye does not see this change in a linear way, the object perceived in both scopes, will have a similar visual response. Yes the 12" will be brighter, but only a smidge brighter.

 

In situations like this it is really to close to call, to choose between a 10" or a 12" scope. I have both, so it doesn't matter. I have compared them both on the same objects, and the difference is there, but you have to look for it.

 

The jump from an 8" to a 10" is more noticeable on all objects, while the small jump in brightness from a 10" scope to a 12" scope is not enough to really discount the 10" by any means, so either one would satisfy. For galaxies you need to subtract 2 magnitudes from the stellar limit, depending on the surface brightness of the object.

 

Deep sky objects like globular clusters will be a smidge more crisp in the 12", and smaller objects like planetary nebula will have a smidge more color and luster, but not much more.

 

The Ultimate Test: I will see if I can get a glimpse of the extremely faint globular cluster, NGC 6749 in Aquila on the next dark, and clear moonless night through both scopes, to test the two aperture's visual power...clear skies...laugh.gif


Edited by dragonstar4565, 27 July 2021 - 07:49 PM.


#43 Starman1

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Posted 27 July 2021 - 06:55 PM

Hello again, I have used both apertures extensively, so I've done my homework. 0.4 magnitudes, is the difference between  detecting an object at the limit of detection in the 10", to seeing the object with averted vision with the 12" scope. 

 

Under dark skies, this would be more noticeable, however it is not a big improvement, and even seeing a very faint 15.5v magnitude or slightly fainter star in the 10" would be detectable 50% of the time in the 10", and detectable with the 12" scope 75% of the time when used at the same power, under the same conditions.

 

When you increase the power in both scopes, fainter stars will be easier to see, and a star right at the limit of both scopes like stated above would have a similar effect, although the star being scrutinized will be slightly easier in the 12" scope allowing the observer to detect it 25% longer then the 10" scope, at any given time.

 

If you really want to brighten up a 15v magnitude star you will need at least a 22" or bigger scope. Even in this aperture the true limit is usually not reached because of seeing conditions, and other factors, such as collimation, although 15v magnitude or fainter is rather routine in this aperture.

 

This is how it works, sense the eye does not see this change in a linear way, the object perceived in both scopes, will have a similar visual response. Yes the 12" will be brighter, but only a smidge brighter.

 

In situations like this it is really to close to call, to choose between a 10" or a 12" scope. I have both, so it doesn't matter. I have compared them both on the same objects, and the difference is there, but you have to look for it.

 

The jump from an 8" to a 10" is more noticeable. The small jump in brightness from a 10" scope to a 12" scope is not enough to really discount the 10" by any means, so either one would satisfy. For galaxies you need to subtract 2 magnitudes from the stellar limit, depending on the surface brightness of the object.

 

Deep sky objects like globular clusters will be a smidge more crisp in the 12", and smaller objects like planetary nebula will have a smidge more color and luster, but not much more...clear skies...laugh.gif

The difference a dark site makes is that a 12.5" scope can go deeper than 17 on stars and deeper than 15 on galaxies.

Bright skies really shave off a lot more than you think.



#44 Pitu

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Posted 27 July 2021 - 08:02 PM

Jump to 16 inch from 10 inch is big difference but 16 inch is BIG and HEAVY! You can see picture of me and my 16 inch dobsonian! That’s why I use homemade ball bearing base that I can move it out and in of my garage. It’s great in Wisconsin that is much darker sky for deep sky objects.  I enjoy my refractor as grab and go also 180mm MakCass for planetary at my home. 

 Lucky you you have garage and you ash and you can take it out or run away from garage on a trolley.

 I can't keep it in a garage because of Dust and humidity.

 I do not have walk out basement so I have to carry everything By hand through the stairs. LOL 😆

 I have to take apart even my 12" because it's heavy it's heavy and doesn't fit through the stairs


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#45 Redbetter

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Posted 28 July 2021 - 12:37 AM

As others have said, this sort of thing comes down to honestly and consistently weighing the trade offs needed for a particular person's situation.  That is why I object to dismissing obvious differences as being inconsequential, e.g.:  "In a nutshell there is nothing a good 12" scope can see, that a good 10" can't see under similar skies"

 

 

 

The jump from an 8" to a 10" is more noticeable on all objects, while the small jump in brightness from a 10" scope to a 12" scope is not enough to really discount the 10" by any means, so either one would satisfy. For galaxies you need to subtract 2 magnitudes from the stellar limit, depending on the surface brightness of the object.

 

10" to 12" is 0.4mag.  8" to 10" is 0.5 mag.  There is very little difference between the impact of the two increments, only 1/4 as much as the smaller increment itself!  If a person finds the 8 to 10" noticeable (I do, for both DSO's and planets.) then the 10" to 12" will be noticeable as well.  

 

The galaxy comment about 2 magnitudes lower limiting magnitude (or thereabouts) pops up a lot, but I don't find it to be representative of dark sky viewing.  For galaxies I find the difference between my stellar and galactic limit is not nearly so large as that, as long as the galaxy's surface brightness is good and the sky is dark. People under estimate galaxy visibility in dark, transparent sky, probably going more off what they experience with increasing levels of light pollution at marginal sites, which harms galaxy visibility much more than it does stars. With the 20" on a good night I'll be reaching 17.5 to perhaps 18 mag stellar if I am lucky (very good seeing allowing very high magnification.)  On the same night for galaxies I will be reaching 17.0 g mag, and I have reached 18.0 B mag on such nights...but I don't put much stock in B mags for galaxies as they generally run 0.5 to 1.0 mag greater than the actual V mags. 

 

This is why I can also detect globulars and galaxies naked eye assuming that they have reasonable surface brightness.   I have seen galaxies and globulars down to about 7.0 mag naked eye in recent years, while my stellar limit recently has been in the low 7's and probably isn't exceeding 7.5.   Much depends on how well placed an object is in the sky.  M55 is quite difficult naked eye because of its combination of modest surface brightness and low position in a brighter portion of sky at my dark sites--of course my stellar NELM is taking a hit that low as well based on what stars I see around it.  

 

 

 

When you increase the power in both scopes, fainter stars will be easier to see, and a star right at the limit of both scopes like stated above would have a similar effect, although the star being scrutinized will be slightly easier in the 12" scope allowing the observer to detect the star 25% longer then the 10" scope, at any given time.

 

0.4 mag is easily the difference between detection or non-detection.  It isn't just a slight difference in how frequently something is seen.   When doing variable star estimates, that is typically 2 steps difference for me compared to reference stars.  Interesting aside, when it comes to steps I will use half step increments to differentiate subtle differences often enough; and it just so happens that that for my calculated difference between an 8 and 10" would be about 2.5 steps, vs. 2 steps for 10 to 12".

 

With reference to 15 mag stars, eyes differ but those are not particular dim in a 20", in fact stars like that can make it hard to detect extremely faint galaxies that they are interposed on or right next to.  15 mag galaxies are straightforward with the 20" unless they are particularly low surface brightness--in which case it comes down to a matter of transparency/contrast/sky darkness on a given night.  15 mag galaxies typically are noted in my logs as "vvF"  or sometimes "vvF/xF" if they are of average surface brightness and therefore larger and harder to detect.  Into the 16's is what I typically find as "xF" and ones at my detection limits are "xxF."

 

Good luck with NGC 6749.  Last time I observed it in the 20" I resolved about a dozen stars across its face.  NGC 6749's main issue is that it is a loose (Class XII) and low surface brightness, like a Terzan or Palomar.  Its total integrated magnitude is still a respectable 12.4, like some of the brighter Terzan and Palomars, and the position in the sky is likely why it is in the NGC while similar magnitude southerly Terzans and Palomars are not.  These are the sort of things most sensitive to dark sky, not aperture so much.  Similarly, in dark sky I can detect Class XI globular NGC 5053 in a 50mm finder.


Edited by Redbetter, 28 July 2021 - 01:03 AM.

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#46 George N

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Posted 28 July 2021 - 10:11 AM

> These are the sort of things most sensitive to dark sky, not aperture so much......

 

It's a sad commentary on the state of 'hobby astronomy' that every discussion of "Newt A versus bigger Newt B" or "commercial-grade A vs premium-grade B" includes a discussion of light pollution.

 

If you can't regularly get to observe under dark sky - telescope quality/type/size is not a real concern - getting to dark sky is. Sky conditions are just far more important than 'equipment' - and should be any observer's first concern.

 

I've owned a telescope of some sort for 66 years - that's a lot of looking. I've never seen a bigger scope that does not show at least a little more than the next smaller size - assuming - dark sky, equal quality, proper cooling and collimation...... all the fun stuff that Newt owners worry about and refractor owners claim that the don't.  wink.gif

 

So -- the 12" is better than the 10"? Personally - if it were my only telescope or my primary telescope with a back-up 'grab & go'  - I'd go with the 12. If I wanted a 'smaller' Dob to 'back fill' behind a "behemoth" in the 18+ class -- the 10 would probably be a better deal because the idea would be 'decent views with the least issues'.

 

Of course then *reality* sets in - and that's different for everyone - $$$, storage, transport, personal goals - anyone thinking about buying a telescope needs to consider the "reality" part before pulling out that credit card. The very best way to do that is -- get to a star party or club observing night and 'observe' - not the skies - but the telescopes and their owners. BTW - anyone from the Northeast -- hope to see you soon on the telescope fields of Stellafane!


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#47 turtle86

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Posted 28 July 2021 - 11:54 AM

> These are the sort of things most sensitive to dark sky, not aperture so much......

 

It's a sad commentary on the state of 'hobby astronomy' that every discussion of "Newt A versus bigger Newt B" or "commercial-grade A vs premium-grade B" includes a discussion of light pollution.

 

If you can't regularly get to observe under dark sky - telescope quality/type/size is not a real concern - getting to dark sky is. Sky conditions are just far more important than 'equipment' - and should be any observer's first concern.

 

I've owned a telescope of some sort for 66 years - that's a lot of looking. I've never seen a bigger scope that does not show at least a little more than the next smaller size - assuming - dark sky, equal quality, proper cooling and collimation...... all the fun stuff that Newt owners worry about and refractor owners claim that the don't.  wink.gif

 

So -- the 12" is better than the 10"? Personally - if it were my only telescope or my primary telescope with a back-up 'grab & go'  - I'd go with the 12. If I wanted a 'smaller' Dob to 'back fill' behind a "behemoth" in the 18+ class -- the 10 would probably be a better deal because the idea would be 'decent views with the least issues'.

 

Of course then *reality* sets in - and that's different for everyone - $$$, storage, transport, personal goals - anyone thinking about buying a telescope needs to consider the "reality" part before pulling out that credit card. The very best way to do that is -- get to a star party or club observing night and 'observe' - not the skies - but the telescopes and their owners. BTW - anyone from the Northeast -- hope to see you soon on the telescope fields of Stellafane!

 

Unfortunately, that's the way it's been for some time and it's only getting worse. frown.gif

 

I think for most people who want to do deep sky observing, the best scope is going to be the largest they can afford and transport to a dark site.  

 

Great advice too about going to a star party to check out other scopes.  Some of these larger scopes need to be seen in person to appreciate their size and heft.


Edited by turtle86, 28 July 2021 - 11:54 AM.


#48 dragonstar4565

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Posted 28 July 2021 - 12:41 PM

Here is a sight I found where Bill F. was able to see a 15.5v magnitude galaxy with his 10" Starfinder near the galaxy NGC 5077. If that's not faint then I don't know what is. I myself have never had the opportunity to go that deep sense I am in a big city. Wow, that is quite amazing that a 10" scope under dark skies can see something this faint. This is where I believe a 10" will give a good run for it's money over a 12" under the same skies. I also found a similar observation near NGC 4281 on the same sight, where MAC 1219+0515 was detected at also 15.5v magnitude. The cut off point for a 10" is a lot deeper, then most think Wow!...clear skies...smile.gif 

 

http://cosmicvoyage.net/n5077.html

 

http://cosmicvoyage.net/n4281.html



#49 RLK1

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Posted 28 July 2021 - 02:07 PM

I continue to see the same or similar statements about size and weight comparos in relation to observing areas.  In the case of the topic at hand, I'd much rather transport a 12" or 12.5" truss assembly in my SUV than a 10" f5 tube. The latter is bulky and therefore a handfull while a truss assembly can be easily disassembled and reassembled in the field. I understand a 12" tube assembly would be even more difficult to move in many instances but the weight and dimensions are known factors from their descriptions on the websites that you buy them from. In other words, a modicum of planning needs to take place before you buy. That said, I'd even prefer to transport my 12" ES truss structure assembled and throw that into the back of my SUV than I would a 10" f5 tube...    


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#50 turtle86

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Posted 28 July 2021 - 03:18 PM

I continue to see the same or similar statements about size and weight comparos in relation to observing areas.  In the case of the topic at hand, I'd much rather transport a 12" or 12.5" truss assembly in my SUV than a 10" f5 tube. The latter is bulky and therefore a handfull while a truss assembly can be easily disassembled and reassembled in the field. I understand a 12" tube assembly would be even more difficult to move in many instances but the weight and dimensions are known factors from their descriptions on the websites that you buy them from. In other words, a modicum of planning needs to take place before you buy. That said, I'd even prefer to transport my 12" ES truss structure assembled and throw that into the back of my SUV than I would a 10" f5 tube...    

 

Agree. If I'm going to go through all the trouble of loading up, making the two-hour drive, and camping at my dark site, I'm going to want to haul the biggest scope I can manage.  For me, that's usually my 18" truss Dob, and sometimes it's my 12.5" truss if time is short (or my lower back is acting up!).  At home, where I have a bit of light pollution and am usually limited to quick peeks anyway, my 10" tube Dob or my refractors tend to get more use since I can deploy them more quickly than my larger truss Dobs.


Edited by turtle86, 28 July 2021 - 03:18 PM.

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