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Why specify glass type if you don't specify optical accuracy?

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#26 Mitrovarr

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Posted 11 January 2021 - 05:23 PM

But if they don’t give you some sort of test results, some sort of confirmed verification or if you don’t have some sort of third party retesting how do you really know what you have ? Do you go strictly by the name of this company, or that company or ........ ? I mean what a way to handle your big $’s and every purchaser of these renowned scopes are in the same way ! Thats sure not the way I would do business, lol !


How do you know what you have? You look through it.

Unless your standards are incredibly high, you should be able to identify any gross deficiencies optically. And while some people might be willing to spend $$$ so they have every tiny scrap of performance, others won't be. It's a fair choice when it really does cost so much money.

#27 LDW47

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Posted 11 January 2021 - 05:39 PM

How do you know what you have? You look through it.

Unless your standards are incredibly high, you should be able to identify any gross deficiencies optically. And while some people might be willing to spend $$$ so they have every tiny scrap of performance, others won't be. It's a fair choice when it really does cost so much money.

You are correct but I would like to know what the ‘every scrap of performance’ is for the cost ? Its a great question which I have always wondered about but never seen answered especially now that some of the important data is not part of it all ! Have you personally been able to tell by just looking through one ?


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#28 Mitrovarr

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Posted 11 January 2021 - 06:01 PM

Realistically any experienced observer can tell if a scope is bad (it won't do what it should for the aperture) and most of them can tell if a scope is mediocre or good. It becomes harder near the top end of scope performance.

That's why I think it only makes sense for the really expensive high end stuff.

#29 Paul G

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Posted 11 January 2021 - 06:38 PM

Is it all marketing?  Deflecting a more important question?  Glass types obviously matter, you want to know that to know colour correction but no optical test means correction could be an issue.  I'd like to know that as much as glass type.

It doesn’t even give you color correction, that’s determined by the mating glasses. And for a given type of glass there are levels of quality so by itself it tells you nothing at all.



#30 RichA

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Posted 11 January 2021 - 07:12 PM

You are correct but I would like to know what the ‘every scrap of performance’ is for the cost ? Its a great question which I have always wondered about but never seen answered especially now that some of the important data is not part of it all ! Have you personally been able to tell by just looking through one ?

Be funny if they incremented up cost in-line with strehl ratio for the same model scope.  "Here's a 0.96 unit, it's $3999.00."  "Here's a 0.985 unit, it's $4999.00."  Be funnier still if people couldn't tell the difference.  I've seen it in the past for a couple different models. 


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#31 CHASLX200

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Posted 11 January 2021 - 07:19 PM

I really don't care about glass type or specs by heck. My eyes tell me all i need to know and many know i know what the heck i am doing when i say a scope has super optics or is a dud buds.  Kinda like all the fluff over the SW150ED and peeps crying they don't know the glass type. My SW150 ED did fine at 450x and i feel there is no need to spend up to 17k for a used 6" AP or around 6K for a used FS152 when the SW150ED does 90% of any of the pricey scopes that cost many times as much.


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#32 LDW47

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Posted 11 January 2021 - 07:22 PM

Be funny if they incremented up cost in-line with strehl ratio for the same model scope.  "Here's a 0.96 unit, it's $3999.00."  "Here's a 0.985 unit, it's $4999.00."  Be funnier still if people couldn't tell the difference.  I've seen it in the past for a couple different models. 

Do you really think, honestly, that they can tell ?


Edited by LDW47, 11 January 2021 - 09:16 PM.


#33 SandyHouTex

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Posted 11 January 2021 - 07:41 PM

They must be happy to get your phone call, lol !

Just making them meet their promises.



#34 LDW47

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Posted 11 January 2021 - 07:45 PM

Just making them meet their promises.

Thats what I figured, lol !



#35 junomike

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Posted 11 January 2021 - 07:58 PM

In this case only when they are looking up on a clear, star filled nite ! With a Porche, with a Volkswagen Beetle, with a ........ its rain or shine, night or day ! The values are kind of different, the logic is kind of different so let me ask again. What do you see different using the Porche of telescopes vs the Volkswagen of telescopes that amazes more than the other after all is said and done ? Just a question, I am curious ? PS: The greater value has to provide something tangible in the eye(piece) of the beholder, hopefully ?

I disagree.  A Corvette or Porsche on the open track is a far vastly different experience than a standard sedan.  Now, how many Corvette's or Porches are used for everyday use?  I'd say almost all of them.

So by your reasoning there's no need for such a car (for most) as you can never "open them up" in the city. So why have 5 or 6 gears when ya can never really get out of 2nd? 

 

Grab a decent 5" Triplet Apo on a avg night pointed at the Planets  and you'll see vastly more than a achro pointed at the same thing.

Now the key is the incremental increase from one to the other.

Some feel the Achro is more than fine and no need for anything else.  Others need "top end" to be happy.  Then some feel mid-tier is good enough for them.

 

Best thing (but not always easiest) is to jump on the "Cost to Performance" train and get of where you're most comfortable.

 

Having been on both sides of the fence, I'll say there's as many people out there rationalizing their decisions due to funds (or there lack of), realism, Etc as there are people out there trying to justify their

purchases (by elevation of views)

 

Bottom line is enjoy what please you but don't expect it to please me!


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#36 LDW47

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Posted 11 January 2021 - 09:03 PM

I disagree.  A Corvette or Porsche on the open track is a far vastly different experience than a standard sedan.  Now, how many Corvette's or Porches are used for everyday use?  I'd say almost all of them.

So by your reasoning there's no need for such a car (for most) as you can never "open them up" in the city. So why have 5 or 6 gears when ya can never really get out of 2nd? 

 

Grab a decent 5" Triplet Apo on a avg night pointed at the Planets  and you'll see vastly more than a achro pointed at the same thing.

Now the key is the incremental increase from one to the other.

Some feel the Achro is more than fine and no need for anything else.  Others need "top end" to be happy.  Then some feel mid-tier is good enough for them.

 

Best thing (but not always easiest) is to jump on the "Cost to Performance" train and get of where you're most comfortable.

 

Having been on both sides of the fence, I'll say there's as many people out there rationalizing their decisions due to funds (or there lack of), realism, Etc as there are people out there trying to justify their

purchases (by elevation of views)

 

Bottom line is enjoy what please you but don't expect it to please me!

Yes but with a Porsche, a Vet, a ..... wherever you are running it as soon as you hit the pedal you know instantly what you have, rain or shine ! With the varying skize of this planet, only occasionally might the high end scope shine vs what you put into it ! With the great medium priced scopes you are never disappointed. I don’t agree with you at all except as you say enjoy what pleases you in any skie conditions as will I !  PS: Other than perceived satisfaction of holding a pricey piece of equipment what does it actually reveal that a good achro or lower cost apo does, thats what counts, surely not little green men, lol ?


Edited by LDW47, 11 January 2021 - 09:08 PM.


#37 junomike

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Posted 11 January 2021 - 09:45 PM

There is a difference and IME you don't need amazing skies to see it, just avg - above avg. 

The main difference is personal ability and preference as not all are in tune to seeing the difference (whether physically or mentally).

Why pay more if there's no difference? 

Why not pay more if there is?

Only the individual can decide and be happy with that choice.


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#38 Mitrovarr

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Posted 11 January 2021 - 09:59 PM

I'd honestly be curious if you guys could see a difference in a blind test between my SW150ED and an expensive triplet. It's really quite nice.


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#39 alan.dang

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Posted 11 January 2021 - 10:55 PM

And you pay big bucks for that perceived consistency with little gain for the majority of astronomers with average eyes under average-good skize ! And then you say they still don’t offer individual reports ??

I ran my now-sold TEC110FL through CCD inspector and it showed collimation of 0.  (Perfect).  The tilt was just 2% using a Canon EF to RF mount as well, which is also very impressive.  Those are the kind of numbers you normally expect with a lot of tweaking and tuning and a pure screw thread design.

 

I am always surprised when I see a first time astronomer or astrophotographer start with something exotic like a Paramount ME and a FSQ130.  The scenario of people spending big bucks just to spend big bucks is definitely something that happens.  However, I think most astronomers who spend big bucks on something have gone through spending small bucks on something else first and made the decision to upgrade based upon experience.  Like most luxury goods, extracting the last bit of performance increases costs exponentially.  However in contrast to fast cars (which you cannot experience on streets) or audiophile equipment (which may not actually provide better performance), you do get measurable improvements with premium optical instruments, even if there is only one day out of the year when the atmospheric seeing allows you to harness the step up in performance.

 

No hobbyist telescope can match the value proposition of Google.  Simply owning a telescope is inefficient.  Some of us have made financial sacrifices elsewhere and saved our money to splurge on getting the last % of optical performance from a telescope.


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#40 Mitrovarr

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Posted 11 January 2021 - 11:03 PM

Honestly, even if you can afford the best equipment right away, I wouldn't do it.

 

It's kind of fun to climb the equipment "tree" and experience multiple levels, and you'd miss out if you went right to a top end apochromat or something.


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#41 LDW47

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Posted 11 January 2021 - 11:11 PM

I ran my now-sold TEC110FL through CCD inspector and it showed collimation of 0.  (Perfect).  The tilt was just 2% using a Canon EF to RF mount as well, which is also very impressive.  Those are the kind of numbers you normally expect with a lot of tweaking and tuning and a pure screw thread design.

 

I am always surprised when I see a first time astronomer or astrophotographer start with something exotic like a Paramount ME and a FSQ130.  The scenario of people spending big bucks just to spend big bucks is definitely something that happens.  However, I think most astronomers who spend big bucks on something have gone through spending small bucks on something else first and made the decision to upgrade based upon experience.  Like most luxury goods, extracting the last bit of performance increases costs exponentially.  However in contrast to fast cars (which you cannot experience on streets) or audiophile equipment (which may not actually provide better performance), you do get measurable improvements with premium optical instruments, even if there is only one day out of the year when the atmospheric seeing allows you to harness the step up in performance.

 

No hobbyist telescope can match the value proposition of Google.  Simply owning a telescope is inefficient.  Some of us have made financial sacrifices elsewhere and saved our money to splurge on getting the last % of optical performance from a telescope.

I understand what you are getting at perfectly, your last paragraph is well said ! And you know I am the same in some of my other interests.



#42 RedzoneMN

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Posted 12 January 2021 - 06:44 AM

I'd honestly be curious if you guys could see a difference in a blind test between my SW150ED and an expensive triplet. It's really quite nice.

With average seeing there will be no difference between the SW150ED and a TOA. Tried it at the club. On clear dark nights there will be a perceptible difference when put side by side and you go from one eye piece to the other. 



#43 CHASLX200

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Posted 12 January 2021 - 06:55 AM

I'd honestly be curious if you guys could see a difference in a blind test between my SW150ED and an expensive triplet. It's really quite nice.

The AVG Joe would never tell the diff.  Only a few of us here could tell. I am sure that a used 6" AP that was going for $17k or that Tak FS152 that is around $6K would give a better image. But is it worth that much more money?  Not to me. But if you have millions then just as well get that last 10% and spend big money. At crazy powers in my good seeing a super well made scope always comes out ahead, as i have seen many times with my Taks and other super pricey scopes. 


Edited by CHASLX200, 12 January 2021 - 06:56 AM.


#44 db2005

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Posted 12 January 2021 - 07:04 AM

The AVG Joe would never tell the diff.  Only a few of us here could tell. I am sure that a used 6" AP that was going for $17k or that Tak FS152 that is around $6K would give a better image. But is it worth that much more money?  Not to me. But if you have millions then just as well get that last 10% and spend big money. At crazy powers in my good seeing a super well made scope always comes out ahead, as i have seen many times with my Taks and other super pricey scopes. 

Based on my experiences with my ED80/ED100 and premium scopes I'm pretty sure I could tell the difference in very short order (like a few seconds at the eyepiece at moderate magnification) - but this does not imply I would have been able to do so a few years ago before I had spent enough time with premium optics and learned to notice and appreciate their qualities.


Edited by db2005, 12 January 2021 - 07:04 AM.

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#45 dan_1984

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Posted 12 January 2021 - 07:17 AM

Just marketting, within reason. Suppose the idea is that if it has FPL-53 then at least you likely have the best glass generally available.

 

Works the same on reflectors - They are specified by diameter and no mention of the optical accuracy. Same thing. Ever read anyone asking "Do I buy a good 8" newtonian or a mediocre 10" newtonian?"

If you buy high quality stuff, you get the specs from the manufacturer, no marketing. Comercial Newts, SCTs, RCs, Fracs are specified by aperture alone because they have average materials, average optics , poor quality control etc. 

A 12 inch newtonian from ASA is > 11000 EUR, 12 inch newtonian from Skywatcher 900 EUR. You get all the info you need from ASA, you get no information from Skywatcher :).

So its marketing for the average stuff!


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#46 bobhen

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Posted 12 January 2021 - 07:26 AM

But if they don’t give you some sort of test results, some sort of confirmed verification or if you don’t have some sort of third party retesting how do you really know what you have ? Do you go strictly by the name of this company, or that company or ........  ? I mean what a way to handle your big $’s and every purchaser of these renowned scopes are in the same way ! Thats sure not the way I would do business not for that kind of $’s, lol !

See my post number 11

 

Many of the high-end producers have been around for almost 50-years so there are plenty of 3rd party test results, reviews etc.  You are right that "new producers" offering high-end telescopes need to do much more than just offer marketing exaggerations they need to offer 3rd part test results, color-crossing and spot diagrams and the glass used, otherwise the consumer is taking " much more" of a gamble.

 

Although the same can be said for "value producers" as well. 2 to 3k for a refractor with no glass designation with only a diffraction-limited guarantee of optical quality, while it might be much less than the high-end producers would charge, is sill “a lot of money" for many.

 

Of course, I would not expect the “value producers” to offer anything and most don’t, except for marketing fluff or exaggeration that tries to convince the consumer into thinking they are getting more for their money, when, if the facts were known, the consumer might actually be getting less. Those producers either say as little as possible or what they say is meaningless or what they “leave out” is actually “more important” than what they say.

 

Buying a telescope is like buying anything else, brand is important, price "can be" an indicator of quality but do your homework and – caveat emptor.

 

Bob


Edited by bobhen, 12 January 2021 - 08:53 AM.

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#47 Jon Isaacs

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Posted 12 January 2021 - 08:39 AM

And on those dark, clear nites what do you see different for the $’s ? Hopefully more than just a feeling of satisfaction ?

 

It's not exactly the dark, clear nights when optical quality is most important, it's those nights with excellent seeing when the planet's and double stars are on the menu .. 

 

That's when having all the colors in focus is most helpful, having the best optics is most helpful.

 

Jon


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#48 LDW47

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Posted 12 January 2021 - 09:25 AM

It's not exactly the dark, clear nights when optical quality is most important, it's those nights with excellent seeing when the planet's and double stars are on the menu .. 

 

That's when having all the colors in focus is most helpful, having the best optics is most helpful.

 

Jon

They should be when some have just paid .......... and then to probably the majority of great fellow astronomers a bit of or lack of color means nothing its just the plain, overall view that counts, thats the most helpful of it all. 



#49 LDW47

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Posted 12 January 2021 - 09:39 AM

I think most supporters of the higher end scopes are just skirting the main issue ie this price for this performance vs this much higher price for a much higher and consistent performance not just occasionally. I mean if one pays 5-6x or more for a scope you would probably like 5-6x, at least, more performance every time you take it out, you peer through it ? And every specification, all data regarding it, they have paid for that I would think ? I know I would demand it ! As years go by, as management changes, policies change, finances change, cash flow changes reputations change as well not always for the better ! Its just the way it is ! As I said I would want every iota of detail of what I was getting before I invested and I probably never will after reading some of this but then again its my choice !



#50 RichA

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Posted 12 January 2021 - 09:46 AM

I really don't care about glass type or specs by heck. My eyes tell me all i need to know and many know i know what the heck i am doing when i say a scope has super optics or is a dud buds.  Kinda like all the fluff over the SW150ED and peeps crying they don't know the glass type. My SW150 ED did fine at 450x and i feel there is no need to spend up to 17k for a used 6" AP or around 6K for a used FS152 when the SW150ED does 90% of any of the pricey scopes that cost many times as much.

We hear this 90% claim a lot.  But I wonder if it is true.  90% what?  Resolution?




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