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Something I like about refractors...

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#26 Mark Costello

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Posted 26 March 2013 - 08:05 AM


..........

I do not get the achro vs apo threads. It is as if refractors are only used to view the Moon, Jupiter, Venus and the 5 brightest stars in the sky. Those objects are less than 1% of my viewing volume.



:waytogo:

I may spend an entire session on the moon and planets when the moon is out. But like you, my approach is: There is one moon, three planets which I regularly observe (Mars, Jupiter, and Saturn), and myriads of other objects within the grasp of my achro.

#27 Sean Puett

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Posted 26 March 2013 - 08:14 AM

So what do people who own multiple examples of each type of telescope defend? :grin:

- Jim


I should be asking you that :grin:. These crazy people still favor one over the other or they favor higher quality versions and defend the money spent for said quality. Refractors are where this example easiest. The apo vs achro endless debate or even mass produced vs awesome dream refractors (or high end). Newts are the same. With the aperture rules crowd and the land of diminishing returns crowd. One older example of newt nerd rage was when a guy who used to own a 15" obsession sold it when he got into astro photography. A few years later he missed having a scope for visual and bought a Zhumell 12" dob. He was excited and very happy with his mirror and scope as a whole and said (paraphrased) "This Z12 has as good a mirror as my obsession. If I had known these were this good, I would have saved a lot of money." he may have even said the view was better than the obsession. Anyway, you can imagine the nerd rage that followed, not quite on par with the "tec140 isn't as good as other high end scope" thread but, still pretty angry responses.

This hobby seems to attract people who are very passionate about their beliefs and I would say the average IQ is higher than the national average. We all love our hobby or we wouldn't spend so much time on the internet writing about it, reading books, or investing serious coin. One of the beautiful things about this hobby is even if you don't make a lot of money, you can buy a telescope that would make Sir Isaac Newton or Galileo jealous for under $300. Modern amateurs have better equipment than a lot of the pros had even 100 years ago. The other side is great also. If you are rich, you can buy any imaginable size and type of telescope.
This is the golden age of amateur astronomy. Now sell all your Cats and buy refractors and newts so you can do it correctly :p Really, there is so much variety that of course there will be difference of opinion and even though not everyone is at the point where they should have an opinion, we will still be reading it. My opinions have evolved since I started and I know that most peoples' will to.

#28 Ed Holland

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Posted 26 March 2013 - 04:10 PM

I should be asking you that :grin:. These crazy people still favor one over the other or they favor higher quality versions and defend the money spent for said quality. Refractors are where this example easiest. The apo vs achro endless debate or even mass produced vs awesome dream refractors (or high end). Newts are the same. With the aperture rules crowd and the land of diminishing returns crowd. One older example of newt nerd rage was when a guy who used to own a 15" obsession sold it when he got into astro photography. A few years later he missed having a scope for visual and bought a Zhumell 12" dob. He was excited and very happy with his mirror and scope as a whole and said (paraphrased) "This Z12 has as good a mirror as my obsession. If I had known these were this good, I would have saved a lot of money." he may have even said the view was better than the obsession. Anyway, you can imagine the nerd rage that followed, not quite on par with the "tec140 isn't as good as other high end scope" thread but, still pretty angry responses.

This hobby seems to attract people who are very passionate about their beliefs and I would say the average IQ is higher than the national average. We all love our hobby or we wouldn't spend so much time on the internet writing about it, reading books, or investing serious coin. One of the beautiful things about this hobby is even if you don't make a lot of money, you can buy a telescope that would make Sir Isaac Newton or Galileo jealous for under $300. Modern amateurs have better equipment than a lot of the pros had even 100 years ago. The other side is great also. If you are rich, you can buy any imaginable size and type of telescope.
This is the golden age of amateur astronomy. Now sell all your Cats and buy refractors and newts so you can do it correctly :p Really, there is so much variety that of course there will be difference of opinion and even though not everyone is at the point where they should have an opinion, we will still be reading it. My opinions have evolved since I started and I know that most peoples' will to.


Well said - I think this is one of the most sensible comments I've read on the forums of late. Especially so amongst the ever growing telescope design debate threads. Sometimes it seems as absurd as arguing that metric wrenches are better than their inch counterparts.

I myself prefer a well balanced and budget minded telescope diet. Yet I still enjoy the wide variety of flavours this has to offer, and love to learn "hands on" about some of the different options. It is a fortunate thing to have such choices :)

#29 stevew

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Posted 26 March 2013 - 04:52 PM

The significance of the apochromat is that now that refractors have been relegated to the realm of consumer hobbyists, modern technologies in glass making and design have been applied to eliminate and/or mitigate all but one of the principal drawbacks of the achromat. Specifically, use of new materials and design tools has allowed creation of shorter, more convenient to mount and operate OTAs with superior color correction. The deficiency of small aperture remains, but two out of three ain't bad.


- Jim

If I'm correct I believe the apochromat was developed with imaging in mind.
We can thank Mr Dennis Taylor and his Cooke Photo Visual telescope objective.
Roland C. and Al N. produced them in smaller apertures for the amateur community,
and soon they also became popular with the visual amateur who wanted the sharpest image per inch.
But Jim is correct, in affordable sizes they are still small aperture telescopes.
However not everyone wants or needs to search out faint Abell galaxy clusters.


Steve

#30 jrbarnett

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Posted 26 March 2013 - 05:39 PM

Or put another way, sometimes it's "pub grub" and others it's "haute cuisine" that fills the hole and suits the belly. :grin:

Ain't no wrong way to eat, and the best Neopolitan-style pizza is always better'n a mediocre rendition of canard à la presse. Now I'm getting hungry.

- Jim

#31 jrbarnett

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Posted 26 March 2013 - 05:45 PM

Jon:

You're all kinds of nutters. And I think you gave it to me, too. Now I know who to blame for those nights when I field a 60mm achromat instead of the 16" Dob, or a 90mm MCT instead of a C8 or C11. It's all your fault!

:grin:

- Jim

#32 moynihan

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Posted 26 March 2013 - 07:07 PM

Somehow, I'm thinking that if Charles Messier walked out onto his roof one night and discovered that the astro-fairies had changed his trusty long-focus 4"achro into a fancy 6"apo, there would have been 220 messier objects, not 110.


Hmmmmm.

I sometimes wonder what his sky looked like.
He and others of his day often worked from within cities, before the electric light.
Think of the first written description of M31, before the first telescope.
An Arab astronomer described it as a candle flame obscured by a thin sheen of bone, seen from a distance. Having seen it naked eye from a former home on many occasions, it is a good description.

This summer i intend to take my Carton 60mm f/15 out into the country side for the fun of it.

#33 CounterWeight

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Posted 26 March 2013 - 07:14 PM

Marvin the Martian seems to have had a preference for refractors, at least in that one.

#34 Scott in NC

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Posted 26 March 2013 - 07:57 PM

There is no right way or wrong way to observe. We just pick the tools that work best for our individual needs.

:ubetcha:

#35 jrbarnett

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Posted 26 March 2013 - 09:21 PM

The heyday of Islamic astronomy ended before there were telescopes. Azophi (European transliteration of "Al Sufi"), a Persian naked eye astronomer, described it as a "little cloud" in the mid 900s. He also first observed and described the Magellanic Clouds.

In 1612 it was Marius, a German astronomer/astrologer, first observed Amdromeda with a telescope and said that it looked like a candle shining through horn. That's probably the description that you're alluding too. Burnham quotes Marius in his essay on M31 in the Celestial Handbook.

Can you name another current hobby where participants discuss other participants who participated in the 900s and 1600s? If law is the second oldest profession, astronomy must be the second oldest hobby. :grin:

As for Messier, most of his observing occurred from an urban Parisian rooftop at the Hotel de Cluny. It's now a museum to the "Middle Ages" with some very nice gardens.

http://tinyurl.com/ccg7msm

Paris in Messier's day was a dirty, wood and coal heated, dank, smelly, and (for a pre-industrial city) well-illuminated city. La Ville-Lumière by edict of Gabriel Nicolas de la Reynie became Europe's first illuminated city in the late 1600s. Parisians were required to keep candles burning in each street-facing window, primarily for crime suppression since de la Reynie also established the metropolitan police force.

If I had to guess, I'd say that by midnight, atop the Hotel de Cluny, Messier might have enjoyed Magnitude 5 skies or a little better at zenith. I'd guess low transparency due to the miasma of smoke, ash and noxious vapors from the city's poor sanitation was as much an issue as illumination. I'd also bet that his telescopes fell a darned sight short of "diffraction limited" in optical quality.

Old Chuck didn't have it so easy, really.

Regards,

Jim

#36 roscoe

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Posted 26 March 2013 - 10:38 PM

This summer i intend to take my Carton 60mm f/15 out into the country side for the fun of it.


I live under 5.5 or so skies, my ATM/Carton 60 does a pretty amazing job! It'll show nearly everything my 120 will, just not as bright.
R

#37 jrbarnett

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Posted 26 March 2013 - 11:22 PM

Neil English and I took along a vintage 60mm f/15 on this trip:

http://www.cloudynig...hp?item_id=2804

Neil even penned a magazine article in the UK covering the trip.

The little 60mm actually did quite well, 0.965" eyepieces and all. Of course, they were 0.965" Takahashi Orthos...:lol:

The scope:

Posted Image

The eyepieces:

Posted Image

Fun, fun.

- Jim

#38 Mariner@sg

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Posted 26 March 2013 - 11:40 PM

Somehow, I'm thinking that if Charles Messier walked out onto his roof one night and discovered that the astro-fairies had changed his trusty long-focus 4"achro into a fancy 6"apo, there would have been 220 messier objects, not 110.


If M. Messier had the 6" apo, I doubt he'll find a need to compile that list! :cool:

#39 HCR32

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Posted 27 March 2013 - 05:06 AM

Your right it would have been a review of the worlds best telescope, The 6" APO! I would have done the same thing.
Even though the APO hasn't put it's name in the history books of discovery, it certainly has put a clearer window in front of our eyes onto our universe with out a doubt.

#40 Jon Isaacs

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Posted 27 March 2013 - 06:20 AM

I sometimes wonder what his sky looked like.
He and others of his day often worked from within cities, before the electric light.



Before electric light to be sure but also before gas and electric heat and power.. Wood and coal fires messed up the skies. And of course Messier lived before the time of the glass mirror with aluminum coatings, the affordable achromat and the apochromat. He cataloged 110 objects during his lifetime. I am quite sure if he had had my 10 inch F/5 GSO Dob and some decent Plossls, we would have a much different list.

Jon

#41 Jon Isaacs

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Posted 27 March 2013 - 06:22 AM


There is no right way or wrong way to observe. We just pick the tools that work best for our individual needs.

:ubetcha:


We pick something anyway... whether we choose the tool that work best for our individual needs, I would have to think, sometimes yes, sometimes no.

Jon

#42 Cotts

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Posted 27 March 2013 - 06:52 AM

Many of us should pause to consider the dollars tied up in the scopes not being used on any given clear night....

Dave

#43 t.r.

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Posted 27 March 2013 - 07:46 AM

Hey Dave, how is the "new" TEC compared to the AP 6"?

#44 jrbarnett

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Posted 27 March 2013 - 10:00 AM

You're probably right, Jon. His list might have looked more like Herschel's list of ~2500 objects. But that would have ruined our marathon prospects, so I'm glad Paris was a polluted city and his equipment was of poor quality. Otherwise we couldn't do in a night what it took he and his collaborators a lifetime to pull off. :grin:

- Jim

#45 chaoscosmos

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Posted 27 March 2013 - 12:34 PM

Something I like about refractors is the sound of the word, "refractor." Has a nice sharp, solid sound to it. Then again, it's a sound you might not want to hear spoken if you have a headache.

#46 Jeff B

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Posted 27 March 2013 - 12:58 PM

Paris in Messier's day was a dirty, wood and coal heated, dank, smelly, and (for a pre-industrial city) well-illuminated city.


And compared to today they've managed to ditch most of the wood and coal heating. :throwveg: :step:

#47 JKoelman

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Posted 27 March 2013 - 01:13 PM

What I like about refractors is that they provide all who don't suffer from aperture fever (aka "help, mine is too small" syndrome) with the perfect night sky instrument.

#48 moynihan

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Posted 27 March 2013 - 03:26 PM

very interesting, and thanks for the correction. Been a long time since i read my Burham. Still have should use them again. your description of his Messier' s conditions probably explains why his list of confusing objects is so short
;)

#49 Crow Haven

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Posted 27 March 2013 - 04:12 PM

So what do people who own multiple examples of each type of telescope defend?

- Jim


Variety is the spice of life! More is better! :grin:

I'm a collector with an optics fetish...
and crows like bright shiny things. :lol:

#50 moynihan

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Posted 27 March 2013 - 04:41 PM

...and crows like bright shiny things. :lol:



:roflmao: how true...excellent!






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