206 replies to this topic

[Jon Isaacs]

1. Portability. One highly recommended beginner telescope is a 6-inch Dobsonian. The telescope weighs 25 lbs. The base weighs 35 lbs. On the other hand, my "grab-n-go" 4-inch refractor and its mount and tripod weigh 25 lbs combined. If you are a small person or you have mobility problems, the portability of a smaller telescope is important. The best telescope is the one that gets used.

 

2. Convenience. My 4-inch "grab-n-go" refractor was in for repairs and I enjoyed using a 5-inch Newtonian (Astronomers Withouth Borders). However, several nights, I wanted to go out, but had not planned on doing so and the telescope had not been collimated. I knew from experience that collimation needed to be set (or at least checked) each time. So, those nights I did not have the use of the nominally "better" telescope with more aperture. Also, just to say, at a local star party I helped one of our stalwarts collimate his 8-inch Dobsonian twice. It took two of us: one to view, one to turn the knobs. One person can do it alone: back and forth... back and forth... back and forth...

 

3. Choice of Aberrations.  An achromatic refractor does have chromatic aberration. An apochromatic has much less (theoretically none, but theoretically also still a tiny bit). A Newtonian reflector has wires ("spider vanes") that create diffraction interference. Some people like the look of that so much that they photoshop spikes into all of their stars. 

 

4. Actual aperture is the actual aperture. With a Newtonian, you have the central obstruction is which is usually given as 25%. (Some makes and models have more.) So, an 8-inch reflector is really a 6-inch aperture. So, the highly recommended 6-inch entry-level Newtonian is really a 4.5 inch entry-level telescope, just heavier to carry in two trips.

 

Those all being my reasons, the fact is that my first adult telescope was a Newtonian, a 130mm Celestron on an equatorial mount and I used it happily for five years and learned a lot about the sky. The best telescope is the one that gets used.

 

I am strictly a visual observer. (I have taken some snapshots with my cellphone.) Observing is my hands-on engagement in the hobby. My primary interest is in writing and I also volunteer as an editor. As much as I support other people's being "Citizen Scientists" I know that I am not. I do not track variable stars or look for comets. I am just a stargazer, as probably 90% of us here are. We are less engaged with celestial objects than birdwatrchers are with their feathered friends. Birdwatchers will put out feeding stations and hang housing from the trees and be mindful about keeping the cat indoors. We do nothing to help the stars. Even photographers contribute very little to science. (I know: there is a counter-argument from a Sky & Telescope article. but the fact remains that most astrophotography is just another kind of stargazing.)

 

Clear Skies,

Mike M.

 

Mike:

 

You have me scratching my head.

 

1. The Orion XT-6 OTA weighs 11.9 lbs, the base 19.4 lbs.  It's only 6 lbs heavier than your 4 inch refractor and equal in weight to my 4 inch apo on its mount.

 

2. Collimation is not a big deal.. it takes a couple of minutes once you know how.

 

3.  Aberrations, chromatic aberration can be much more damaging than spider diffraction or a central obstruction. Chromatic Aberration is light out of focus light.

 

4. Aperture is not as simple as you say.  In terms of light gathering it goes by area and reflectivity.  A 25% CO only reduces the area by 6%.  In terms of resolution, aperture is aperture, the Dawes limit for a 6 inch scope is not affected by a central obstruction.

 

In general, I believe refractors make the best small scopes, assuming your willing to pay for ED optics. They're efficient and they a versatile. But they do not scale up well.  

 

I really don't know the demographics of telescope ownership and use. Certainly there are many who use SCTs and Maks for their compact performance, many who use Dobs and other Newtonians for their simplicty and optical prowess. And there are many who refractors.

 

I think most amateurs own scopes of more than one type. No one type can do it all. 

 

Jon

[Dave Mitsky]

I think most amateurs own scopes of more than one type. No one type can do it all.

Amen to that!

[dawnpatrol]

 

 

I think most amateurs own scopes of more than one type. No one type can do it all. 

 

This.
 

[mikemarotta]

Thanks, Jon. I agree with you on all points. (I checked my algebra. Ratio of [A1 = (pi) * R1)^2] / [A2=(pi) * (R2)^2] and, yes, 1/16 ~ 6%. ) As for the weights, yes, again, I was in error. I was thinking of the last one I had to lift and carry, an Explore Scientific 8-inch: 25 lbs tube and 21lbs rocker.

 

Mike:

 

You have me scratching my head.

 

1. The Orion XT-6 OTA weighs 11.9 lbs, the base 19.4 lbs.  It's only 6 lbs heavier than your 4 inch refractor and equal in weight to my 4 inch apo on its mount.

2. Collimation is not a big deal.. it takes a couple of minutes once you know how.

3.  Aberrations, chromatic aberration can be much more damaging than spider diffraction or a central obstruction. Chromatic Aberration is light out of focus light.

4. Aperture is not as simple as you say.  In terms of light gathering it goes by area and reflectivity.  A 25% CO only reduces the area by 6%.  In terms of resolution, aperture is aperture, the Dawes limit for a 6 inch scope is not affected by a central obstruction.

In general, I believe refractors make the best small scopes, assuming your will to pay for ED optics. They're efficient and they a versatile. But they do not scale up well.  

I really don't know the demographics of telescope ownership and use. Certainly there are many who use SCTs and Maks for their compact performance, many who use Dobs and other Newtonians for their simplicty and optical prowess. And there are many who refractors.

I think most amateurs own scopes of more than one type. No one type can do it all. 

 

Jon

 

I agree that "collimation is not a big deal" unless it is not done at all and at dark-thirty you cannot do it (or not do it well). I agree, of course, that refractors do not allow for ever-greater diameter, which is why Hale's telescope at Yerkes was 40 inches and at Mount Palomar 200 inches. If you have an "obsession" for aperture, there is a fix your jones. And, yes, I also have a reflector now and I started in the hobby with a reflector. So, I am not unaware. I have also sung the praises of the AWB 130-mm Newtonian which with my Nagler eyepiece gave me a "walk in space" view, not delivered even by my apochromatic refractor.

 

The question was why do refractors remain popular. I  just stated the reasons for my preferences.

 

Thanks, again,

Mike M.

 

PS The Rev. Mr. Dawes disallowed the value of the so-called "Dawes Limit." It says nothing about the quality of the telescope.

Edited by mikemarotta, 28 January 2023 - 10:11 PM.

[Jon Isaacs]

 

PS The Rev. Mr. Dawes disallowed the value of the so-called "Dawes Limit." It says nothing about the quality of the telescope.

In your post, you wrote that the effective aperture of a reflect was not it's full aperture. In terms of resolving power, a reflectors resolving power is based on its full aperture. 

 

 

If you have an "obsession" for aperture, there is a fix your jones.

I do not have an "obsession for aperture." I have an obsession for observing the universe, for observing as much of the universe as possible. And that means have a full set of tools.

 

Refractors are popular just as other types of telescopes are popular. In understanding why they're popular, one has to understand both their capabilities and their limitations.

 

Jon

[tony_spina]

In your post, you wrote that the effective aperture of a reflect was not it's full aperture. In terms of resolving power, a reflectors resolving power is based on its full aperture.

I do not have an "obsession for aperture." I have an obsession for observing the universe, for observing as much of the universe as possible. And that means have a full set of tools.

Refractors are popular just as other types of telescopes are popular. In understanding why they're popular, one has to understand both their capabilities and their limitations.

Jon

Perfectly said. I love my refractors, but I love that I have choices to use the right scope for the observation opportunity at hand

[Echolight]

Mike:

 

You have me scratching my head.

 

1. The Orion XT-6 OTA weighs 11.9 lbs, the base 19.4 lbs.  It's only 6 lbs heavier than your 4 inch refractor and equal in weight to my 4 inch apo on its mount.

 

2. Collimation is not a big deal.. it takes a couple of minutes once you know how.

 

3.  Aberrations, chromatic aberration can be much more damaging than spider diffraction or a central obstruction. Chromatic Aberration is light out of focus light.

 

4. Aperture is not as simple as you say.  In terms of light gathering it goes by area and reflectivity.  A 25% CO only reduces the area by 6%.  In terms of resolution, aperture is aperture, the Dawes limit for a 6 inch scope is not affected by a central obstruction.

 

In general, I believe refractors make the best small scopes, assuming your willing to pay for ED optics. They're efficient and they a versatile. But they do not scale up well.  

 

I really don't know the demographics of telescope ownership and use. Certainly there are many who use SCTs and Maks for their compact performance, many who use Dobs and other Newtonians for their simplicty and optical prowess. And there are many who refractors.

 

I think most amateurs own scopes of more than one type. No one type can do it all. 

 

Jon

If collimation is so simple, why is it that you use $500 worth of tools AND a pair of binoculars to do it 

[Protheus]

If collimation is so simple, why is it that you use $500 worth of tools AND a pair of binoculars to do it 

I hope that's not a serious comment.  I can collimate a Newtonian roughly with no tools at all.  It won't be right on, of course.  A decent Cheshire combo tool, which will put it right on, more easily if you've got a center spot, is something like $35.

 

Chris

[Echolight]

I hope that's not a serious comment.  I can collimate a Newtonian roughly with no tools at all.  It won't be right on, of course.  A decent Cheshire combo tool, which will put it right on, more easily if you've got a center spot, is something like $35.

 

Chris

I’m sure that I underestimated. 

[Jehujones]

If collimation is so simple, why is it that you use $500 worth of tools AND a pair of binoculars to do it 

because they can, that's why 

[mikemarotta]

I do not have an "obsession for aperture." I have an obsession for observing the universe, for observing as much of the universe as possible. And that means have a full set of tools.

 

 

It was meant as a general comment with the generic "you" for "one person" and a pun on the Obsession brand of large instruments for hobbyists, again, meant to underscore the very points you are making. I am not looking for an argument here. 

 

We do have different interests vis-a-vis this hobby and I believe that I recall your owning microscopes, which I do, also. As I noted above, however, our engagement in astronomy is entirely passive: we cannot influence the objects we study. And we all are limited by the environments in which we observe. You haul a large reflector out to the desert. I view from the city with a small refractor. While you do have a much better view, you do not have a better understanding. You are where Herschel and Parsons were 200 years ago. And even with a spectroscope, you are still in 1920.

 

I am writing an article this weekend and next for my local club newsletter about the Orion Nebula. My sources include C. Robert O'Dell's book but also his papers and recent papers by others. (I am a huge fan of the Harvard Astrophysical Database System archive of journal articles.)  Only with the James Webb Space Telescope are we now able to gather significant information in the infrared wavelengths to reveal more of what has always been hidden by the veil of dust and gas. Short of that, you might as well be out in the backyard on a chaise with a binocular seeking the Trapezium, which is perfectly valid as a pastime. I am just not a passionate telescopic observer. I read history, theory, and the history of theory, and I do so, like you, to understand the universe.

 

Best Regards (and Clear Skies),

Mike M.

[Jon Isaacs]

If collimation is so simple, why is it that you use $500 worth of tools AND a pair of binoculars to do it

 

The same reason I built a jig to collimate my $4000 4 inch refractor instead spending $400 plus shipping to have TeleVue do it.  It's not like refractors never need collimation.

 

Having good tools and knowing how to use them is nice.. Particularly when you're collimating a scope with an 8 or 10 foot focal length those binoculars are great.

 

Mike was discussing the commonly recommended 6 inch F/8 Dob. Collimation tolerances are lax.

 

Jon

[Tony Flanders]

To some extent, this question might better be posed as "Why are small-aperture scopes so popular?"

Given the choice to use a small aperture, refractors have numerous advantages over other designs. That's especially true for apertures of 80 mm or less, where it's actually hard to find any kind of scope other than a refractor. There are a handful of 70-mm Maks running around, and 76-mm Newts are viable as starter scopes. But the smallest widely used catadioptrics are 90-mm Maks, and the smallest widely used Newts have 114-mm mirrors.

The basic reasons that refractors work so well in small apertures is that they have no central obstructions and they have a virtually unlimited focusing range. Both of those are serious issues for small-aperture Newts and many catadioptric designs.

 

More to the point, the disadvantages of refractors -- which are overwhelming in large apertures -- are very minor in small apertures. For any given kind of glass and focal ratio, a refractor's false color is directly proportional to its aperture. So a 60-mm f/10 flint/crown achromat has barely perceptible false color, whereas a 200-mm f/10 flint/crown achromat has terrible false color.

 

For any given aperture, refractors are the least portable and most problematic design, due to the fact that you're viewing from the bottom of a long tube. That means that the eyepiece height varies more than it does for any other design, and that you need a taller and heftier tripod than you do for any other design.

 

Consider, for instance, my Z130, a 130-mm f/5 tabletop pseudo-Dob. When it and I are both sitting on surfaces at essentially the same height, I can view all the way from the horizon to the zenith in perfect comfort. The entire setup, including the table and the chair, is trivial to carry in a single trip.

 

Now consider a 130-mm refractor. You have three choices: use a small focal ratio and accept the massive false color, use exotic glass and a focal ratio likely around f/8, or use flint/crown with a focal ratio around f/15. The APO will have a tube roughly one meter long, and the achromat around twice that. Moreover, due to the heavy objective, most of that length ends up behind the pivot point. So even if you're sitting on a low stool, the pivot point needs to be really high when you're viewing (say) 60 degrees above the horizon. In practice, you end up needing a really tall, really heavy tripod for any refractor with a focal length much longer than a meter.

 

However, those disadvantages become very modest in small apertures. A really short refractor, like my 70-mm f/6.9, with its 480-mm focal length, works well on any half-decent tripod, and the variation in eyepiece height is easy to handle. Once the focal length gets up to 600 mm the eyepiece height becomes more of a problem, but it's still easy to accommodate with an adjustable-height chair, and you still can get away with a pretty modest tripod.

 

So, in short, if you want a scope with an aperture of 80 mm or less, a refractor is by far the most practical design unless you're really poor or need something ultraportable, and even at 100 mm the benefits of a refractor outweigh the downsides for many people. Once you get bigger than that, refractors start to become more of a specialty item.

 

Which then begs the question, why use a small-aperture scope? And the answers to that are obvious -- wide field of view, portability, and faster cooldown time.

[Chad7531]

At star parties, on all CN boards and even talking to friends, they are all about buying the best refractor with the best glass. Overall, I’m a newbie to this amazing hobby but have been here since 2019 but have been studying science/astrophysics forever.

Is the main thing about refractors the wide field view and observing DSO and Astrophotography? Because the aperture is so small on refractors and people are going crazy about 72mm, 90mm and 102mm scopes. Anything above that is so expensive.

An SCT or Dob gives so much aperture for planets and solar system objects but their narrow field of view is what the refractor fans are annoyed at?

(disclaimer: I am considering buying a refractor to supplement my Celestron 9.25 and to possibly double mount it).

Something I’ll never fully understand myself. My smallest scope is a 6” f5 reflector that cost $300. It can provide 3.5* tfov, magnification over 500x, no CA, cools in under a half hour, weighs 13lbs, and is collimated in 30 seconds with a $5 tool. I would need to spend like $5,000 to get comparable performance from a refractor. Cool down and collimation time savings would be negligible, I might start viewing 15 minutes earlier, who cares. I’d rather use a newt focuser than basically be sitting on the ground, I don’t really sit anyway so that’s a deal breaker in itself.

If I want a field wider than 3.5* or just want to observe with no setup, I’ll get out my $100 binoculars.

I wouldn’t mind piggybacking a small refractor on my 10” dob, that actually sounds pretty awesome. But I would never waste my money and time just to observe with one on its own when I already have scopes that do everything better.

Edited by Chad7531, 29 January 2023 - 07:14 AM.

[dnayakan]

I will add that different people find different aberrations and artifacts annoying. Some can’t stand chromatic aberrations and a lens system inherently has that problem. Some loathe coma which parabolic mirrors are susceptible to. Spherical mirrors can have field flatness issues. Mirrors, in general scatter more light and reduce throughput and the spider vanes can cause diffraction spikes that you may love or loathe. 
 

All designs are compromises where you take advantage of what that design does well and try to find ways to minimize the inherent flaws of that design.

 

If you are unaffected by a particular aberration, you will wonder what all the fuss is about - exotic, expensive glasses and uncomfortably long focal lengths to minimize an issue an issue that mirrors eliminate automatically can sound silly to your ears/eyes. But no more so than using curved spiders to reduce diffraction spikes and exotic shaped primaries and secondaries and paracorrs might sound to others.

 

It is partly an aesthetic response. You can provide different mathematical proofs to mathematicians or different chess mating solutions to chess experts. These experts will tell you that all approaches solve the problem (a proof or a checkmate) but will exhibit a preference for one solution as being ‘more elegant’. 
 

Also worth pointing out that different targets can make different aberrations obvious/annoying. Star clusters can be annoying if you have coma or an insufficiently flat field. If you like hunting for faint, extended objects, you will be annoyed by a lack of aperture but may not care at all about coma. 

 

There are regions where particular designs come into their own. And that is smaller apertures for refractors and larger apertures for reflectors. Various other aspects of your observing experience (observing conditions, ability to deal with fiddle small vs. heavy large instruments, targets you like viewing etc.) might push you towards some spot on that aperture range. 
 

It’s a bit like arguing the merits of red vs. white wine. Some enjoy one to the exclusion of the other. I would argue that finding out about your preferences is a good thing, but not understanding other preferences can be silly. There is merit to understanding how our circumstances/experiences constrain our preferences. However, closing ourself off to other experiences feels like impoverishing our own existence. A bit like a white wine lover complaining about the lack of floral notes and sweetness in red wines. 
 

Cheers, DJ

Edited by dnayakan, 29 January 2023 - 07:37 AM.

[JoshUrban]

That's a misconception. The refractor can go on its own dovetail and be mounted on the larger scope. When you're done you just take it off. It can then be independently mounted on its own mount.

Even if you're not mounting the secondary scope with a dovetail. About the only other option is to have rings permanently mounted on the primary scope. In that case you can get a second set of rings on a dovetail and pull the secondary scope off the primary scope by opening the rings, which is not hard, putting it into the second set of rings with their dovetail and again you're ready to go.

Unless one has an observatory, it would be a bad idea to leave the secondary scope on the primary scope in any case. So you always have the grab and go potential. You would need a Twilight or similar mount for such applications.

RIGHT!  Forgot about the dovetail.  My old club had a Borg 5" refractor mounted on a C14.  It was nice to compare the views between them.  Apples and oranges, and both delicious.  

[Wildetelescope]

Lots of good reasons listed here.  For me personally, I have a range of reasons for visual use of my refractors.

 

1. Climate- Much of the year, I will see 5-10 degree shifts in temperature over the course of an evening.  Also plenty of dew.  Larger mirror systems, particularly cats, are challenged with this.  There are of course solutions, to this, but that is a bit more work. *

2. Seeing conditions-  I live under the Jet stream.  4-5 inches is kind of optimal for me.  

3. Convenience- an f8-9 100 mm refractor is in my opinion probably the optimal combination of light grasp and portability.  It is also useable with a resasonable range of eyepieces.  While refractors do occasionally require a bit of attention with respect to collimation, it is not as often as with Newts.  And I do not have to contend with diffraction spikes on the planets.  Also I find a refractor mounted at the correct height more pleasurable to view through than my 10 inch dob(which will show more than ANY of my refractors, hands down).  

4. Aesthetics- No one has said this, but I think refractors look cool:-).   I would never claim my 6 inch F9 refractor is convenient to set up, but it gives me great views and just looks way cool:-)

 

Short anecdote in regards to point 3.   I had my TV102 out on my AZ8 manual mount at an outreach event with my club.  The other scopes were an 8 inch Cat, a 14 inch SW goto Dob, and a 10 inch Discovery dob.  It was a cloudy, hazy night.  So we were all looking at planets and the moon.  We had over 200 folks come through and over the course of the night, i had MANY folks tell me that my little refractor gave them the best views.  Now, I have looked through my friends 14 inch sw many times.  the optics are very good, and he is experienced and keeps it collimated.  there is No way my little TV 102 should give better, more detailed images of the moon or planets.  Same is true for the Discovery dob, which that night I actually went over and looked through.  The view of the moon was excellent and very sharp.  At LEAST as nice to my eye as it was in my little scope with respect to contrast although at a higher magnification.  And certainly, I could see smaller craterlets more easily in the dob:-). 

 

So why were people saying that they liked the view from my little refractor the best?  I believe it was point three.  I had my scope set up at a height that was easy for most adults to bend over and look through without too much fuss.  For the children, I had my adjustable star bound chair set up so they could kneel on the seat and look through the eyepiece. No need for parents lifting them or for them to look through the eyepiece and an oblique angle.   Finally, for each person, I would ask them what they saw, and then had them go back and take a longer look.  There are probably other variables like seeing and how I framed the target that probably also contributed, but simply having things set to the right height so that folks could be comfortable looking through the scope for a longer period is probably what did the trick.  

 

Now of course this can be done for pretty much any scope, including dobs, (I hear you Jon:-). But at least for me a 4 inch refractor, my starbound chair and the AZ8 is the simplest combination I can think of to accommodate 5 year olds to adults my size(6’3”). 
 

 

cheers!

 

JMD

 

*Edit: Finished my thought:-)

[Keith Rivich]

I think the virtues of the refractors have been stated quite nicely, and accurately, in the post above. One thing I do not see mentioned is that simply stated a well built refractor is just plain sexy to look at. Like a Ferrari or a McLaren. Dobs are like trucks. Some are works of art but they are still trucks.

 

Refractors are what a telescope is supposed to look like. Even at outreach visitors know how to look through a refractor. They have to be shown where the eyepiece is in a newt...

[epee]

Aperture is certainly king, quality is queen and the mount is the minister. A truly regal reflector is cheaper and and sets up easier and faster than a refractor of equal capability. 

 

However, the sky is Emperor and all are at his mercy. Since many haven't or do not desire a dedicated observatory in darksky country or can store or wish to set-up a large reflector at their home, a small, easy to deploy, refractor fits the bill.

 

I personally attest to the capability of a 4" apo under clear, dark skies. Certainly a 12' Dob can trump that, but I can't toss that Dob on top of camping gear at a whim, just in case the skies and circumstances allow. Nor can I put the 12", mount and all, across my shoulder and walk to a clear spot. Even if I could, I wouldn't have the wide field views I get with a sub-$500 f/6 102mm apo.

 

To argue reflector vs. refractor is like arguing Lamborghini vs. Truck.

[Echolight]

Aperture is certainly king, quality is queen and the mount is the minister. A truly regal reflector is cheaper and and sets up easier and faster than a refractor of equal capability. 

 

However, the sky is Emperor and all are at his mercy. Since many haven't or do not desire a dedicated observatory in darksky country or can store or wish to set-up a large reflector at their home, a small, easy to deploy, refractor fits the bill.

 

I personally attest to the capability of a 4" apo under clear, dark skies. Certainly a 12' Dob can trump that, but I can't toss that Dob on top of camping gear at a whim, just in case the skies and circumstances allow. Nor can I put the 12", mount and all, across my shoulder and walk to a clear spot. Even if I could, I wouldn't have the wide field views I get with a sub-$500 f/6 102mm apo.

 

To argue reflector vs. refractor is like arguing Lamborghini vs. Truck.

Uh oh, uh oh! Infinity apo?

[GGK]

If you main interest is visual astronomy - start at the 102mm. The frenzied interest in the smaller models is 99% astrophotography.

WooHoo!  I'm a one percenter now!  

 

Probably 25% of my viewing time is with my 60mm f/6 doublet with a 5^o - 7.4^o degree field.  Using the refractor rather than binoculars provides the options of adjusting max field and exit pupil to best fit the image as well as jumping to higher magnification when wanted (within the limits of the scope).

 

Ultrawide fields aren't for looking at object detail, of course, but instead for observing the star patterns, very large objects, and putting many DSOs in one view.  Last night I had Orion's belt and sword in view and was looking at a bowl or semicircle asterism that encircles half the belt with about 11 stars visible in the 60mm.  I need about 6.5^o for the best image of that.  

 

It's sort of like looking at the beauty of an entire meadow at once rather than the beauty of a flower's petal within that meadow.

 

I'd move to a 60mm f/5 Petzval for 8.9^o, if they made one with enough back focus for a diagonal, but no luck yet.

 

Gary

[Victory Pete]

It kinda goes like this

https://m.youtube.co...h?v=xaK4r0pQaJ0

You forgot one:

 

https://youtu.be/pJh9OLlXenM

[Jon Isaacs]

Aperture is certainly king, quality is queen and the mount is the minister. A truly regal reflector is cheaper and and sets up easier and faster than a refractor of equal capability. 

 

However, the sky is Emperor and all are at his mercy. Since many haven't or do not desire a dedicated observatory in darksky country or can store or wish to set-up a large reflector at their home, a small, easy to deploy, refractor fits the bill.

 

I personally attest to the capability of a 4" apo under clear, dark skies. Certainly a 12' Dob can trump that, but I can't toss that Dob on top of camping gear at a whim, just in case the skies and circumstances allow. Nor can I put the 12", mount and all, across my shoulder and walk to a clear spot. Even if I could, I wouldn't have the wide field views I get with a sub-$500 f/6 102mm apo.

 

To argue reflector vs. refractor is like arguing Lamborghini vs. Truck.

 

 

It doesn't seem that way to me. The refractor is grossly underpowered.  It's an easy to drive, rather slow vehicle. A reflector is more capable, much more capable but requires more effort to operate..  both have their virtues. A morecapt comparison might be a Mazda Miata versus a Corvette. 

 

I'm unaware a 102 mm F/6 ED doublet available the US for under $500. Interesting. 

 

My 12.5 doesn't take up much space, it's 19"d20" footprint and 28 inches tall.   

 

 

I am a big believer in two cars as well as two scopes. Underdark does. I nearly always set up and nice small refractor and a Dob of some sort.

 

Yin and Yang..

 

Jon

[bigeastro]

"Aperture is certainly king, quality is queen and the mount is the minister. A truly regal reflector is cheaper and and sets up easier and faster than a refractor of equal capability."

 

I guess for visual the above works.  However for imaging the mount is king, aperture is queen and quality is the minister.

[JOEinCO]

....I wouldn't have the wide field views I get with a sub-$500 f/6 102mm apo....

....I'm unaware a 102 mm F/6 ED doublet available the US for under $500. Interesting....

 

I'm curious to hear about this sub-$500 scope, too.