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Should I jump from 10 inches to 15 or 18?

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#26 Jon Isaacs

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Posted 27 December 2018 - 02:48 PM

Going from 10" to 15" is a substantial jump, about 0.9 magnitude.  Jumps that big tend to have a "wow factor."  15 to 18" is an additional 0.4 magnitude, but 1.3 magnitude over the 10".    Since you are keeping the 10" the question is more of where the extra aperture becomes a hassle/problem to transport and use.  That depends on you and your situation. 

 

Consider how you would use the new scope, how you will transport it/how it will fit when loaded, what additional stuff you will need with it (e.g. ladders or observing chairs), who will be along with you for the trip, and the associated stuff for camping, etc.  Plan for a scope that you can reliably load/unload without any help.  This should help you define the maximum practical size for your needs.  And consider whether you will still be able to handle the same scope in 5 to 10 years.   

 

There is some advantage to maximizing the useful aperture while one is young--better eyes and better fitness for using the scope, rather than realizing one can no longer go bigger a decade or two later.  However, if you undershoot a little on aperture, it is no great loss either.  You might find some things are incrementally out of reach, but should have a more manageable scope as compensation.  It will probably not be enough of a difference that you will actually regret undershooting and end up switching to the next size up.  On the other hand, if you overshoot by an increment it could very well limit the usefulness of the scope to you in a significant way. 

 

:waytogo:

 

This..   Particularly  the last line: 

 

"On the other hand, if you overshoot by an increment it could very well limit the usefulness of the scope to you in a significant way."

 

Most big scopes don't get used a great deal.  Slightly smaller but more often is preferable to larger but a just bit too big.  

 

What do you enjoy observing?  

 

What are you hoping to see in a larger scope ?

 

How tall are you? 

 

How often do you observe? 

 

I often see people recommend the biggest scope you can manage,  the biggest scope you can afford..  And yet I see numerous people buy a large scope , have it for a while but not use it much and then part ways with it.  A big scope that gets used 50 to 100 nights a year is not all that common. 

 

Between 15 inch and 18 inches is 16 inches and there's a lot to be said for a 16 inch. It's goes a full magnitude deeper than a 10 inch,  is only a quarter magnitude down from an 18 inch but can be more easily managed than an 18 inch and more moderate focal ratios are still flat footed. 

 

Jon


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#27 stargazer193857

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Posted 27 December 2018 - 05:36 PM

Night vision is not a replacement for a 20". It just is a different eyepiece for your case.
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#28 stargazer193857

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Posted 27 December 2018 - 05:41 PM

16" if you are 6' tall, 15" if you are 5'8". Although, if you plan to stand all night, a hand rail would steady you, at which point an extra step is not so bad.

Jon's 22" is already at a dark sky site. But even there, he says it is work to set up.

Edited by stargazer193857, 27 December 2018 - 05:44 PM.

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#29 Mike Wiles

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Posted 27 December 2018 - 06:04 PM

I went through this same dilemma back in 2001.  I was making the jump from an 8", and was torn between a 15" and an 18".  I went with the 15" because it would fit through a standard door easily to get it in and out of the house.  It is/was also light enough that I could pick it up and carry it.  This turned out to be the best decision.  An 18" would have required a small ladder for me, and use of the wheelbarrow handles.  This would have caused it to get used less than I have used the 15" in those years since.  

 

My 15" Obsession has been the most useful money I've ever spent in astronomy.  


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#30 stargazer193857

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Posted 27 December 2018 - 06:10 PM

I went through this same dilemma back in 2001. I was making the jump from an 8", and was torn between a 15" and an 18". I went with the 15" because it would fit through a standard door easily to get it in and out of the house. It is/was also light enough that I could pick it up and carry it. This turned out to be the best decision. An 18" would have required a small ladder for me, and use of the wheelbarrow handles. This would have caused it to get used less than I have used the 15" in those years since.

My 15" Obsession has been the most useful money I've ever spent in astronomy.


Makes me want one.
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#31 a__l

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Posted 27 December 2018 - 08:33 PM

My 15" Obsession has been the most useful money I've ever spent in astronomy.  

Everything is relative and depends on many factors. For example I have the opposite opinion.

 

ps. Not applicable to the Obsession brand.

pps. I actually use several telescopes that can be called reasonable by size.

In my opinion more correctly, which is more disappointing. On Cloudy little written (excluding Chinese products). 

In my case it is SIPS, 14.5" mirror, 80 mm finder and some other.
This may be included in the telescope size specified in the header thread, but may be not included.


Edited by a__l, 27 December 2018 - 09:09 PM.


#32 Eddgie

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Posted 28 December 2018 - 10:26 AM

NV is tempting, and folks are thoroughly enjoying the medium. I get the urge periodically and go hinting for equipment. But I feel it doesn't provide the full resolution of a 20". Maybe not even a 10". Correct me if I'm wrong, of course.

You would be surprised. 

 

Last night Peter and I met CN member FeedTheNeed at Mansfield Dam near Austin.  He had been wanting to view though NV and we finally had a chance to show him.  He had read a lot about it and had thought maybe we were overstating what the views would be, but after 5 minutes, he said that he was shocked to see that it was even better than we describe it!  

 

 

Modern NV can show more resolution than most common laptop computers (the Alienware Laptop I am typing this on has 1920 vertical lines of resolution.  A modern NV device can show 2240 lines of resolution (64 line pair per millimeter over a 17.5mm viewing area).

 

This is as it turns out much higher resolution than the scotopic human eye can show and this means on bright targets, it is very easy to resolve very fine detail. (This works out to 1.6 arc minutes of angular field, which is about twice what the scotopic eye can see, and since many objects are very bright with NV, this means a lot of cones fire, so you are are often getting mesopic resolution levels). 

 

From a dynamic range perspective, the picture above cannot show it the way the eye sees it.  The dynamic range is quite amazing.  In the picture above, the core is burned out from the camera, but at the eyepiece, there is a huge amount of detail to be seen.

 

Again, the camera in the above picture was a cheap cell phone camera and it was hand held to the eyepiece, but it shows the amount of nebulosity that can be seen, but it cannot capture the fine detail that is possible to see visually because it lacks the dynamic range, and most computer screens don't have the same range as the view in the NV device does.

 

If you asked FeedTheNeed, I bet he would tell you that as much as we talk it up, he would say that it was better than he thought it would be.  You have to see it I guess, but the resolution and dynamic range is quite excellent. 

 

I could never go back to standard eyepiece use.   There it is all about aperture, and exit pupil limits mean that you are trapped in a viscious cycle of ever larger scopes with ever diminishing true fields of view. With NV, there is no exit pupil limit so you can do things like use a 56mm eyepiece with an f/5 scope, which makes the scope f/2.5.  


Edited by Eddgie, 28 December 2018 - 10:37 AM.

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#33 JaredLeeNewton

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Posted 28 December 2018 - 10:33 AM

waytogo.gif

 

This..   Particularly  the last line: 

 

"On the other hand, if you overshoot by an increment it could very well limit the usefulness of the scope to you in a significant way."

 

Most big scopes don't get used a great deal.  Slightly smaller but more often is preferable to larger but a just bit too big.  

 

What do you enjoy observing?  

 

What are you hoping to see in a larger scope ?

 

How tall are you? 

 

How often do you observe? 

 

I often see people recommend the biggest scope you can manage,  the biggest scope you can afford..  And yet I see numerous people buy a large scope , have it for a while but not use it much and then part ways with it.  A big scope that gets used 50 to 100 nights a year is not all that common. 

 

Between 15 inch and 18 inches is 16 inches and there's a lot to be said for a 16 inch. It's goes a full magnitude deeper than a 10 inch,  is only a quarter magnitude down from an 18 inch but can be more easily managed than an 18 inch and more moderate focal ratios are still flat footed. 

 

Jon

First off, thanks to everyone for the responses. I'm always confident when I post a question in these forums, as I usually get reliable feedback, which is important in our hobby, because it is not the cheapest. Again, always appreciated.

Now to answer some of Jon's questions, which will help fine tune some feedback Ill receive,

-I enjoy general purpose observing, based on the best available objects at my location for a given session. Planets and DSO's I both love.

-I've been observing since I was 11, and I'm 32 now. I've had a 6inch dob and now own a 10 inch dob, which i've had for 10 years now. Just wanting to continue to grow my reach and wealth of detail seen in observing.

-I am 6' 4". Weigh 225. and I'm fairly fit.

- I observe anytime i'm allowed, as dictated by the weather in Kentucky lol.

PS. I've been researching the Obsessions and Teeters quite extensively, and when I decide to pull the trigger, one of them is what Ill probably go with. 

Continue the discussion.



#34 Jon Isaacs

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Posted 28 December 2018 - 10:51 AM

-I am 6' 4". Weigh 225. and I'm fairly fit.

 

You're 32, been observing 20 plus years, you're big and strong.  You might want to look at a 20 inch... 

 

Jon


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#35 bobito

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Posted 28 December 2018 - 10:59 AM

If you have an account on Astromart, an 18" f/4.5 Obsession just popped up in your neck of the woods...  


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#36 25585

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Posted 28 December 2018 - 01:33 PM

Yes, this is exactly what I would recommend too.

 

 

Current scope will pick up a couple of magnitudes, equalling maybe a 20" or larger aperture, but in the same small package.

 

Plus (and this is a big big big plus), because you can use long pass filters to defeat a great deal of light pollution, the range of targets available expands greatly.

 

Galaxies that you struggle to see today will usually be better. 

 

Nebula will be titanic. 

 

Not cheap, but cheaper than a 20" dob, and a lot easier to use.  

 

This is not a many hour long exposure.  It was taken with a cheap Andriod Cell Phone simply held up to the eyepiece. The phone made the exposure (about 10 seconds).   There is no post processing or anything.

 

This was taken from a red zone sky using a 12" f/4.9 dob. 

 

And this picture fall far short of showing the richness of the structure at the core of the nebula.   In that region, using the eye, it is like rich, burled walnut. 

 

This is green but new devices can also be purchased that have white displays (I have one, but in many ways I prefer the green).

 

Again, this is a cell phone picture simply held up to the eyepiece of the device (device was used at prime focus):

 

attachicon.gif Orion.jpg

 

This is the type of device used for this picture.  It plugs into the focuser just like any other eyepiece:

 

attachicon.gif Micro in hand.jpg

Eyepiece and OIII is green. Not sure which I prefer, are white more expensive?



#37 Mike Wiles

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Posted 28 December 2018 - 01:59 PM

You're 32, been observing 20 plus years, you're big and strong.  You might want to look at a 20 inch... 

 

Jon

This was my first thought too....if the budget permitted, a fast 20" scope would be the perfect scope in that situation to me....  The reason I didn't buy one was that back when I bought my 15" I was not 6'4".  I am also still not 6'4".  

 

Knowing that information.....I'd say go for the 18".  A 15" would be almost too small.  It was perfect for me because I'm only 5'6" - I'd need a step up for the 18".  At 6'4", that's flat footed observing anywhere in the sky.  


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#38 Starman1

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Posted 28 December 2018 - 03:30 PM

Ive been an avid observational astronomer for a while now. Wanting to expand my viewing experience. I have mag 5 to 6 skies where I live in Kentucky, and can drive to fairly dark sites. Im going to keep my 10 inch as I plan to give it to my daughter when she gets older. Im wanting to know, from people with experience in this switch, pros and cons of 15 inches vs. 18 inches. Also is 15 enough of a jump for a wow factor, or should I just consider the 18? Let it begin lol

It is my opinion that IF you are going to bother to change telescope size at all that you should jump a full magnitude.

That is a 16" from a 10".

Why?

--everything will appear radically different.  You'll want to go back and re-observe every object seen with the smaller aperture because of that profound difference.

--the number of new objects that will become visible with be in the high scores of thousands.  With 16", galaxy groups will begin to take on new meaning, and the big, bright, local stuff

(out to 100mly), will provide spectacular images.

--the size is still reasonable for a 16".  I can fit a 16" truss dob in the rear of my VW GTI, for instance, which means you don't necessarily have to have a huge, low-mileage, vehicle to transport it places.

--the eyepiece height is still reasonably low on a 16".  Given your height--no ladder required, even if the focuser is not directly side-mounted.

 

An 18" is really a lot bigger and heavier than a 16".  I know that doesn't make a lot of sense, but, having seen multiple examples of both sizes, were I to make the leap to 18", I'd simply move on to 20".

A 16" with a thin mirror is not enormously heavy and large.  An 18" is.

One thing I recommend in either case: A tailgate mirror cell design with a separate case for the mirror.  Then nothing will be intimidatingly heavy as you get older.  And, it will make the scope easier to sell

when moving up to a 25" (one magnitude jump from a 16").grin.gif


Edited by Starman1, 28 December 2018 - 03:31 PM.

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#39 Asbytec

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Posted 28 December 2018 - 07:00 PM

You would be surprised. 

 

From a dynamic range perspective, the picture above cannot show it the way the eye sees it.  The dynamic range is quite amazing.  In the picture above, the core is burned out from the camera, but at the eyepiece, there is a huge amount of detail to be seen.

 

With NV, there is no exit pupil limit so you can do things like use a 56mm eyepiece with an f/5 scope, which makes the scope f/2.5.  

Eddgie, first thanks for not being offended or defensive and answering in the spirit of sharing knowledge. I was not intending to be offensive or a naysayer. I might be surprised, especially with technology today. I am aware my views are still tainted by lower tech images I've seen. 

 

When I was observing M42 core region the other night, I was struck by the beauty and realized this is what I enjoy about observing. Maybe the dynamic range was the term I was searching for above. I guess that is what I would hate to lose most despite the fact we can see more detail. So, the idea of swapping a smaller aperture for a big one and losing that range caused me to ask the question about whether going to EAA was the way to reduce aperture and still enjoy observing - in the same way. From what I gather lurking on some NV threads, NV offers a new way to observe. Almost a new paradigm with different challenges and rewards. Not better or worse, really, just a little different. 

 

The idea of no exit pupil is interesting. Our eye will still have a pupil. But, that's an academic topic to explore another time. 

 

Anyway, so to remain on topic...again, the idea was to use NV and transition to a smaller scope. Which asks the question...is that the way to go? Apparently for a growing number of people it is for their own esoteric reasons for making the transition from visual to NV and other forms of EAA. 



#40 charotarguy

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Posted 29 December 2018 - 10:58 AM

You would be surprised.

Last night Peter and I met CN member FeedTheNeed at Mansfield Dam near Austin. He had been wanting to view though NV and we finally had a chance to show him. He had read a lot about it and had thought maybe we were overstating what the views would be, but after 5 minutes, he said that he was shocked to see that it was even better than we describe it!


Modern NV can show more resolution than most common laptop computers (the Alienware Laptop I am typing this on has 1920 vertical lines of resolution. A modern NV device can show 2240 lines of resolution (64 line pair per millimeter over a 17.5mm viewing area).

This is as it turns out much higher resolution than the scotopic human eye can show and this means on bright targets, it is very easy to resolve very fine detail. (This works out to 1.6 arc minutes of angular field, which is about twice what the scotopic eye can see, and since many objects are very bright with NV, this means a lot of cones fire, so you are are often getting mesopic resolution levels).

From a dynamic range perspective, the picture above cannot show it the way the eye sees it. The dynamic range is quite amazing. In the picture above, the core is burned out from the camera, but at the eyepiece, there is a huge amount of detail to be seen.

Again, the camera in the above picture was a cheap cell phone camera and it was hand held to the eyepiece, but it shows the amount of nebulosity that can be seen, but it cannot capture the fine detail that is possible to see visually because it lacks the dynamic range, and most computer screens don't have the same range as the view in the NV device does.

If you asked FeedTheNeed, I bet he would tell you that as much as we talk it up, he would say that it was better than he thought it would be. You have to see it I guess, but the resolution and dynamic range is quite excellent.

I could never go back to standard eyepiece use. There it is all about aperture, and exit pupil limits mean that you are trapped in a viscious cycle of ever larger scopes with ever diminishing true fields of view. With NV, there is no exit pupil limit so you can do things like use a 56mm eyepiece with an f/5 scope, which makes the scope f/2.5.


Not as experienced as eddgie up here, I can second what he said up here, from my beginners point of view nv is the only one thing that has lived up to the hype. Often times there’s so much of a colorful picture painted as if it would be the only thing that would revolutionize the way one observes but often times a ton of variables are attached to it so the experience from one person to other is so different. I feel NV has the least amount of gap between expectations and reality. That’s my two cents worth of opinion, but then it doesn’t matter as my daughter says my opinion doesn’t matter cause I drive a minivan 🤣 🤣 🤣.
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#41 TareqPhoto

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Posted 29 December 2018 - 11:28 AM

And quoting your thread's title, should i jump from 7"-8" reflector to 16"-20", i feel i want 18", 16" later i feel it is still smaller than what i want, and if 20" then later i will think it is too big, so i feel 18" dob is already so big that i shouldn't exceed.



#42 RobTeeter

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Posted 29 December 2018 - 03:01 PM

We get questions like this all the time, specifically "I have a 10inch and am looking for the next jump...". Usually this ends with a 16" or 18", and rarely 20". Like Don Pensack says, there's a big difference between 16" and 18" that doesn't seem to fit the profile of a 2" difference. To me it's because the 16" can be loaded without ramps and without a second person. Granted it's at the limit but someone such as the OP it sounds certainly doable*. The 18" is just that much more heavy and the boxes just that much wider where the weight and the girth make the boxes awkward to handle alone. So then you're looking at doing ramps or always have a second person to help load and unload. Further, the stacked height from ground board feet up to the tips of the altitude bearings gets taller with an 18" over the 16" (in general, but there are exceptions) so you end up needing a slightly larger vehicle (think SUV compared to CUV) to haul the 18" than you do the 16".

 

*The caveat here is if the scope does not have a ServoCat system, or if it does the owner is comfortable messing with the altitude drive cable in the dark. If a ServoCat system is installed that essentially locks the mirror box to the rocker box and makes the two boxes one unit, unless you want to unwrap (and then re-wrap) the altitude drive cable each time the scope is put into or taken out of your vehicle. I've found most people don't want to mess with doing that, but I've spoken to others who are completely fine doing it. If you don't want to wrap/unwrap the cable then the combined weight of the 16" mirror box and rocker box is beyond what most people are comfortable lifting, let alone carrying any appreciable distance. 

 

There are some variables here to consider and options of scope design to figure out. 

 

Good luck with your research and future purchase.  Take care,


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#43 Redbetter

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Posted 29 December 2018 - 04:46 PM

That is one of the reasons I have not been interested in driven systems.  Disassembly and reassembly would be in the dark 90% of the time for me.  Hauling/packing around things also becomes more complex.   I don't have to worry about powering everything on multi-night trips.

 

Removing the DSC's from my 20" was one of the more liberating things I have done.  Not having to worry about wrecking the encoder shafts, etc. made it so much easier to load tightly in the truck bed.  I wasn't getting any accuracy from them anyway so never used them to find a single object in the field.  (I may have resolved some of the confounding issues since then so that they would work better, but have not been interested in trying it again.)  The increase in portability has been well worth it. 


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#44 25585

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Posted 29 December 2018 - 05:20 PM

It is my opinion that IF you are going to bother to change telescope size at all that you should jump a full magnitude.

That is a 16" from a 10".

Why?

--everything will appear radically different.  You'll want to go back and re-observe every object seen with the smaller aperture because of that profound difference.

--the number of new objects that will become visible with be in the high scores of thousands.  With 16", galaxy groups will begin to take on new meaning, and the big, bright, local stuff

(out to 100mly), will provide spectacular images.

--the size is still reasonable for a 16".  I can fit a 16" truss dob in the rear of my VW GTI, for instance, which means you don't necessarily have to have a huge, low-mileage, vehicle to transport it places.

--the eyepiece height is still reasonably low on a 16".  Given your height--no ladder required, even if the focuser is not directly side-mounted.

 

An 18" is really a lot bigger and heavier than a 16".  I know that doesn't make a lot of sense, but, having seen multiple examples of both sizes, were I to make the leap to 18", I'd simply move on to 20".

A 16" with a thin mirror is not enormously heavy and large.  An 18" is.

One thing I recommend in either case: A tailgate mirror cell design with a separate case for the mirror.  Then nothing will be intimidatingly heavy as you get older.  And, it will make the scope easier to sell

when moving up to a 25" (one magnitude jump from a 16").grin.gif

As an illustration, compare the same area of sky shown in 2 different sky atlases, one showing at least a magnitude more charted than the other. The 1st and 2nd editions of Sky Atlas 2000.00 is an example, 2nd edition going down to 9, while first was to 8.

 

For a big aperture jump, you will have to re-learn the sky. Very bright stars are dazzling, those which were dimmer become misleading at first as they show as bright as very noticable ones in your smaller scope. Its exciting!



#45 ICit2

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Posted 29 December 2018 - 06:02 PM

Eddgie, first thanks for not being offended or defensive and answering in the spirit of sharing knowledge. I was not intending to be offensive or a naysayer. I might be surprised, especially with technology today. I am aware my views are still tainted by lower tech images I've seen. 

 

When I was observing M42 core region the other night, I was struck by the beauty and realized this is what I enjoy about observing. Maybe the dynamic range was the term I was searching for above. I guess that is what I would hate to lose most despite the fact we can see more detail. So, the idea of swapping a smaller aperture for a big one and losing that range caused me to ask the question about whether going to EAA was the way to reduce aperture and still enjoy observing - in the same way. From what I gather lurking on some NV threads, NV offers a new way to observe. Almost a new paradigm with different challenges and rewards. Not better or worse, really, just a little different. 

 

The idea of no exit pupil is interesting. Our eye will still have a pupil. But, that's an academic topic to explore another time. 

 

Anyway, so to remain on topic...again, the idea was to use NV and transition to a smaller scope. Which asks the question...is that the way to go? Apparently for a growing number of people it is for their own esoteric reasons for making the transition from visual to NV and other forms of EAA. 

"From what I gather lurking on some NV threads, NV offers a new way to observe. Almost a new paradigm with different challenges and rewards. Not better or worse, really, just a little different."

 

I would have to respectfully disagree.  NV is not just a little different.  There is a huge difference.  The biggest impact it has on visual observation is the use of a 7nm or 12nm Ha filter that allows you to clearly see nebulae in the city while shutting out the light pollution.  You can't do that with a 16" or 18" mirror.  In fact, the larger apertures in and around the city are typically more vulnerable to sky glow as well as seeing. 16" or 18" is a large column of air to contend with in town.  However, I wouldn't advocate going to a smaller aperture from the 10" you already have.  You could, but the the 10" is going to be transformed with NV.  The only upgrade would be maybe to a faster system. 


Edited by ICit2, 29 December 2018 - 06:03 PM.

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#46 Asbytec

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Posted 29 December 2018 - 06:15 PM

"From what I gather lurking on some NV threads, NV offers a new way to observe. Almost a new paradigm with different challenges and rewards. Not better or worse, really, just a little different."

 

I would have to respectfully disagree.  NV is not just a little different.  There is a huge difference.  The biggest impact it has on visual observation is the use of a 7nm or 12nm Ha filter that allows you to clearly see nebulae in the city while shutting out the light pollution.  You can't do that with a 16" or 18" mirror.  In fact, the larger apertures in and around the city are typically more vulnerable to sky glow as well as seeing. 16" or 18" is a large column of air to contend with in town.  However, I wouldn't advocate going to a smaller aperture from the 10" you already have.  You could, but the the 10" is going to be transformed with NV.  The only upgrade would be maybe to a faster system. 

I'll buy that, makes sense. Being ignorant of NV, what I meant by a little difference was the potential loss of dynamic range, if any. I guess there is some. But, that is a trade off by amplifying dimmer nebula. And I agree, you can filter out light pollution for a higher contrast and amplified image. Its easy to see how this is a big difference. Bigger than using visual LP filters. 



#47 Kunama

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Posted 29 December 2018 - 07:29 PM

I see NV as just another tool, like the LOA21 eyepieces I recently bought, but I think those who advocate NV as the only way to do this hobby are missing out on the beautiful subtle colours that NV does not present.

Seeing the beautiful star colours, especially in clusters like the Kappa Crucis cluster or 47Tuc is one of the most beautiful aspects of visual astronomy, as are the subtle hues of M42 or Eta Carina. 

 

I can fully understand that someone wants to use NV, but don't limit yourself to a small scopes because image intensifiers can bring out stars more brightly. The most spectacular views I have seen in over 4 decades of looking up have been from a scope with a bit of aperture, seeing details of familiar targets with the resolution and colour delivered by Allan Wade's 32" Black Widow are forever etched into my memory banks.

 

Don't sell yourself short .....


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#48 ICit2

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Posted 29 December 2018 - 09:08 PM

I see NV as just another tool, like the LOA21 eyepieces I recently bought, but I think those who advocate NV as the only way to do this hobby are missing out on the beautiful subtle colours that NV does not present.

Seeing the beautiful star colours, especially in clusters like the Kappa Crucis cluster or 47Tuc is one of the most beautiful aspects of visual astronomy, as are the subtle hues of M42 or Eta Carina. 

 

I can fully understand that someone wants to use NV, but don't limit yourself to a small scopes because image intensifiers can bring out stars more brightly. The most spectacular views I have seen in over 4 decades of looking up have been from a scope with a bit of aperture, seeing details of familiar targets with the resolution and colour delivered by Allan Wade's 32" Black Widow are forever etched into my memory banks.

 

Don't sell yourself short .....

Agreed, some targets are better viewed without NV.  And for those I simply uncouple the PVS14 with a twist of the wrist.  But gee-whiz a 32" Black Widow?   Sure **** well better deliver the goods!  Unfortunately, very few of us can afford or transport and set up a 32" scope.   We've all seen gorgeous and well appointed monster scopes for sale on CN.  The reasons vary.  But often it boils down to it's too much of a hassle to drag them out.  And so guys start thinking about something more manageable once the big scope honeymoon is over.  I would offer that a 12" f/5 or faster dob fitted with a PVS14 would see much more use due to ease of transportation, setup and reach.  And if possible check out NV at a star party before taking the 20" plunge. 

 

Here's an example of what NV can produce under cat 5 skies with a 8" newt.  These images represent what I saw at the eyepiece.  But I would add the real thing looks better. No bull.

 

Without NV:

 

Horsehead without Night Vision 8" scope
 
With NV:
 
Horsehead  with Night Vision 8" scope

 


Edited by ICit2, 29 December 2018 - 09:10 PM.

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#49 Starman1

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Posted 30 December 2018 - 12:30 AM

It seems odd that someone who advocates for night vision devices would mention "cannot afford" in the same paragraph.

For the price of one night vision device and a basic 12" scope, you could have a fairly high end 15-16" scope.


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#50 Redbetter

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Posted 30 December 2018 - 01:39 AM

 

Here's an example of what NV can produce under cat 5 skies with a 8" newt.  These images represent what I saw at the eyepiece.  But I would add the real thing looks better. No bull.

 

Without NV:

 

 

Uhhh...my finder shows more than that in Bortle 5/6 transition skies...even my 2.3x binocs showed me that LM with less than 5 mins of total dark adaptation after walking away from the PC. 


Edited by Redbetter, 30 December 2018 - 03:08 AM.



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