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

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#51 RichA

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Posted 12 January 2021 - 09:47 AM

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

They who?



#52 LDW47

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Posted 12 January 2021 - 09:49 AM

They who?

Who ever you were talking about ! In your post #30 I believe, in your response to my post !


Edited by LDW47, 12 January 2021 - 09:50 AM.


#53 RichA

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Posted 12 January 2021 - 09:50 AM

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. 

"Clear, dark night."  Deepsky, at 100x, or planets only at 350x?



#54 Daniel Mounsey

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Posted 12 January 2021 - 09:53 AM

This is a very entertaining thread. lol.gif


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#55 RichA

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Posted 12 January 2021 - 09:53 AM

Who ever you were talking about ! In your post #30 I believe, in your response to my post !

I'd have to know the observer. 



#56 RichA

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Posted 12 January 2021 - 09:56 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

Even deepsky views can be differentiated in good and not as good scopes as power climbs on nights that support it.   A 127mm achromat will clearly show differences that a 100mm apo won't at lower powers, but boost power on something like a globular cluster and the colour correction of the apo can  tip the balance when it comes to the view. 


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#57 Daniel Mounsey

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Posted 12 January 2021 - 09:57 AM

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. 

That's where it gets tricky for them because they often don't understand why they're seeing them in the first place, and often they judge prematurely because they're not seasoned enough in all conditions to know any better. 


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#58 Daniel Mounsey

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Posted 12 January 2021 - 10:02 AM

People have become so consumed by the hype of color correction and marketing, it's become as bad as steroid abuse in the bodybuilding industry. The factor visual observers are missing specifically is "optical figure" because they more often than not, don't know how to tell.


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#59 RichA

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Posted 12 January 2021 - 10:05 AM

IMO very few manufacturers are going to "waste" premium glass on poor optical figure and/or quality.

Sure, some may be better then others, but overall they are usually all in the same league

That's probably the case, but there have been exceptions.  Seeing some of the thorough testing done by people with interferometers makes me believe there are differences in the high-end too, mostly having to do with consistency, though less so than in the mass market.



#60 LDW47

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Posted 12 January 2021 - 10:10 AM

I'd have to know the observer. 

Figure it out they are your words !



#61 Jon Isaacs

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Posted 12 January 2021 - 10:24 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 !

 

This thread is not about whether high end scopes are worth it, it's about knowing what you're buying.

 

In terms of what an expensive scope offers in the way of performance, the more you spend, the closer you are to perfection.. if $500 buys 90% perfect, $1000 might buy 95% perfect and $2000 might buy 97.5% perfect.

 

Jon


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#62 doctordub

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Posted 12 January 2021 - 10:30 AM

I guess that $4000 gets you 98.75%.

CS

Jonathan


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#63 LDW47

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Posted 12 January 2021 - 10:31 AM

People have become so consumed by the hype of color correction and marketing, it's become as bad as steroid abuse in the bodybuilding industry. The factor visual observers are missing specifically is "optical figure" because they more often than not, don't know how to tell.

And most don’t care or want to know, they just want to enjoy what they see not the trivialities of it all that change with the skize ! 



#64 LDW47

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Posted 12 January 2021 - 10:34 AM

This thread is not about whether high end scopes are worth it, it's about knowing what you're buying.

 

In terms of what an expensive scope offers in the way of performance, the more you spend, the closer you are to perfection.. if $500 buys 90% perfect, $1000 might buy 95% perfect and $2000 might buy 97.5% perfect.

 

Jon

Its all one and the same and everyone twists it a little bit to suit themselves ! As far as you putting your finger on those %ages ?? And I am continually asking what is the increase in performance that follows the price, what is the perfection mean in tangible performance over the ........ ? I am just trying to correlate, to envision all of this !


Edited by LDW47, 12 January 2021 - 10:38 AM.


#65 Mitrovarr

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Posted 12 January 2021 - 10:49 AM

Its all one and the same and everyone twists it a little bit to suit themselves ! As far as you putting your finger on those %ages ?? And I am continually asking what is the increase in performance that follows the price, what is the perfection mean in tangible performance over the ........ ? I am just trying to correlate, to envision all of this !

The problem is, it's tricky, and sometimes it matters more for certain applications.

 

For instance, a low end triplet might not even be as good for planetary as a low end doublet (despite costing a lot more and being heavier), because it's faster and has more elements so the figure isn't quite as good. But it would be a lot better for AP because perfect color correction is important there when it's not so important visually.



#66 LDW47

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Posted 12 January 2021 - 11:01 AM

The problem is, it's tricky, and sometimes it matters more for certain applications.

 

For instance, a low end triplet might not even be as good for planetary as a low end doublet (despite costing a lot more and being heavier), because it's faster and has more elements so the figure isn't quite as good. But it would be a lot better for AP because perfect color correction is important there when it's not so important visually.

You are throwing specific factors into the mix and if you are starting to talk AP then things might change drastically from that end of the hobby ! 



#67 Mitrovarr

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Posted 12 January 2021 - 11:23 AM

Yeah, but you kind of have to talk about AP when you talk about fancy refractors. All the really expensive ones are, at a minimum, intended as dual use imaging/visual scopes. Many of them are straight up astrographs where visual use is secondary if anything.

#68 bobhen

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Posted 12 January 2021 - 11:30 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 ! 

You wont get 5 or 6 times the performance out of a high-end refractor because it costs 5 or 6 times more. Just as you won’t get 5 or 6 times the performance from a Ferrari Superfast that costs 5 or 6 times more than a Mustang GT. It costs more and more to keep eking out ever better performance.

 

But it also works the other way as well.

 

Just because one pays 2 to 4 times the price for an ED refractor over a less expensive long-focus achromat does not mean one will be getting 2-4 times the performance from that ED refractor.

 

Want the best “performance value” for the buck, get a long focus achromat with a high quality lens or buy that Mustang GT. Want the “absolute best performance” get the Ferrari or an apo triplet refractor from a high-end maker.

 

Bob


Edited by bobhen, 12 January 2021 - 11:32 AM.


#69 LDW47

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Posted 12 January 2021 - 11:42 AM

You wont get 5 or 6 times the performance out of a high-end refractor because it costs 5 or 6 times more. Just as you won’t get 5 or 6 times the performance from a Ferrari Superfast that costs 5 or 6 times more than a Mustang GT. It costs more and more to keep eking out ever better performance.

 

But it also works the other way as well.

 

Just because one pays 2 to 4 times the price for an ED refractor over a less expensive long-focus achromat does not mean one will be getting 2-4 times the performance from that ED refractor.

 

Want the best “performance value” for the buck, get a long focus achromat with a high quality lens or buy that Mustang GT. Want the “absolute best performance” get the Ferrari or an apo triplet refractor from a high-end maker.

 

Bob

Still trying to compare scopes and cars, no relation !  But if you aren’t getting that much more performance after spending that much more on a scope, we aren’t talking autos, then what does that tell you about the value for $ ? We aren’t talking the wonderful looks, the perceived smoothness of operation, the great tube color we are talking about the views of an object in a black sky. And the persons just plain desire to own one is not a factor as well ! 



#70 LDW47

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Posted 12 January 2021 - 11:45 AM

Yeah, but you kind of have to talk about AP when you talk about fancy refractors. All the really expensive ones are, at a minimum, intended as dual use imaging/visual scopes. Many of them are straight up astrographs where visual use is secondary if anything.

If you are bringing AP into it now, it wasn’t talked about before, then 99% of the past posts mean nothing, you are talking a different scenario !



#71 Gofr

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Posted 12 January 2021 - 11:47 AM

Still trying to compare scopes and cars, no relation !  But if you aren’t getting that much more performance after spending that much more on a scope, we aren’t talking autos, then what does that tell you about the value for $ ? We aren’t talking the wonderful looks, the perceived smoothness of operation, the great tube color we are talking about the views of an object in a black sky. And the persons just plain desire to own one is not a factor as well ! 

I think it just comes down to some folks willing to spend whatever it takes for "perfection", even if it's in reality insignificant. Perfectionists don't care, all they care is that they have perfection, at whatever the cost, whether it's actually noticeable or not.



#72 Mitrovarr

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Posted 12 January 2021 - 11:52 AM

Want the best “performance value” for the buck, get a long focus achromat with a high quality lens or buy that Mustang GT. Want the “absolute best performance” get the Ferrari or an apo triplet refractor from a high-end maker.

Bob


I actually don't think long focus achromats win performance value anymore. You will spend more than the cost of an entry level doublet on the mounting difference. Long focus achromats take the largest mount per unit aperture of any design.

Also, good luck finding a decent one.

#73 Mr. Mike

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Posted 12 January 2021 - 11:57 AM

This thread is not about whether high end scopes are worth it, it's about knowing what you're buying.

 

In terms of what an expensive scope offers in the way of performance, the more you spend, the closer you are to perfection.. if $500 buys 90% perfect, $1000 might buy 95% perfect and $2000 might buy 97.5% perfect.

 

Jon

Correct. And do make note of the diminishing returns phenomena as you spend more and more.  Every last percentage point of viewing bliss costs one dearly. The ultra high end has worked that way with scopes and really any other hobby other products.  
 

As for glass types, it feels like the glass type is sort of a marketing sticker that they put on the box or something. Sure, it does matter but perhaps not quite as much as the entire package and of course the overall value of what you get.  Kind of like: "now with 20% more FPL-53 glass". lol.gif


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#74 LDW47

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Posted 12 January 2021 - 11:58 AM

I think it just comes down to some folks willing to spend whatever it takes for "perfection", even if it's in reality insignificant. Perfectionists don't care, all they care is that they have perfection, at whatever the cost, whether it's actually noticeable or not.

But if its not noticeable how do you know, how can you say its perfection other than the cost for which you have just paid ? I mean is turning the focuser knobs smoothly perfection, the well fitting lens cover is it perfection, the .......... ? They say you don’t even get all the technical details of its lenses which should be a price factor, a perfection factor ! I once was, in my transportation career, a perfectionist but the job insisted it, but not any more ( for the most part ) so I know the workings of a perfectionists mind, the processes, lol ! It is a big factor !



#75 LDW47

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Posted 12 January 2021 - 12:02 PM

I actually don't think long focus achromats win performance value anymore. You will spend more than the cost of an entry level doublet on the mounting difference. Long focus achromats take the largest mount per unit aperture of any design.

Also, good luck finding a decent one.

Yes but the good mount can be used for future scopes, it is not a one scope entity. Buy it now or buy it later but you will always have a use for it.




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