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What does optical quality cost?

refractor optics
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#1 db2005

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Posted 06 June 2020 - 06:39 AM

Much of the price we pay for high-quality refractors is due to optical quality, i.e. the quality of lens figure and polish. Of course, the cost of glass/fluorite blanks also depends on material quality. It is my understanding, however, that we pay more for the workmanship going into the optical surface than the material they are made of. Optical quality doesn't occur by accident but by quality workmanship. Experience at the eyepiece also confirms that optical quality is a real thing, and more expensive optics perform better than inexpensive optics.

 

But I wonder how long time and how much effort it actually takes to manufacture a premium-quality optic, say a Tak FC-100 versus a more common ”run-of-the-mill” optic (say, something like a ED100).

 

In other words, what is the manufacturing costs of optical quality? Supposing a given premium optic is priced at 3-4x more than a run-of-the-mill optic, would that also imply that the premium optic is 3-4x as expensive to make, because of the additional attention to lens figure and polish? And is the additional cost incurred because of extra time for hand-finishing high-end optics, or is the cost simply incurred by needing machines to work longer and slower on the lenses for a better finish?

 

Can anyone offer some reliable information about that? Any insights as to the cost-breakdown of making high-end optics?

 

Thanks,

Daniel


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#2 randcpoll

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Posted 06 June 2020 - 07:20 AM

When you pay a premium for something it is often more related to technology or 'trade secrets' behind the manufacturing and not the manufacturing cost in itself. Then you also have the upcharge for the branding that has distinguished itself.


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#3 db2005

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Posted 06 June 2020 - 07:55 AM

There is probably some truth in that... but anyone familiar with Zemax or similar raytracing software can "theoretically" reverse-engineer premium optics from specs and may even convince themselves that that they could build their own. But actually figuring and polishing the surfaces to the desired figure and smoothness would seem to be another thing entirely, involving using actual tools and knowing the quirks of how optical glass and lens-making tools behave during processing, etc.

 

I am pretty convinced that more actual work is being done on premium optics vs. run-of-the-mill optics. Otherwise run-of-the-mill optics would be just as good as the premium counterparts.


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#4 Scott in NC

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Posted 06 June 2020 - 08:19 AM

Yes, I do believe that that in many cases we’re paying for the name and reputation of the manufacturer, but if that reduces the chance of getting an optical lemon from 1 in 10 to 1 in 100 then I’m okay with that.  I think (but of course have no way of proving) that we’re also paying for the time and care spent figuring and aligning the optics, assembling the mechanical parts, and performing final QC.  Time is money.  And if it takes 3-4 times the time to do the job right, and I’m paying twice the price, then I’m also okay with that.


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#5 Alan S

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Posted 06 June 2020 - 08:56 AM

There is also economy of scale. Manufacturing many pieces can bring down the cost of individual pieces.

On the TEC users group, Yuri provided a breakdown of his recent price increase. It is interesting, and not surprising.

Alan
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#6 Scott in NC

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Posted 06 June 2020 - 09:00 AM

On the TEC users group, Yuri provided a breakdown of his recent price increase. It is interesting, and not surprising.

I hadn’t read that yet, but look forward to checking it out.  It’s nice to know that in our little niche market we’ve got craftsmen that are willing to share that information.



#7 Astroman007

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Posted 06 June 2020 - 09:05 AM

"What does optical quality cost?" As much as you can afford to pay.



#8 rerun

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Posted 06 June 2020 - 09:19 AM

Additional to the costs for the optics ,an employee at Takahashi earns more money than a chinese worker I would assume. Wages and salaries also make up a large part of the total costs. So Tele Vue , TEC ,Takahashi are more costly out of this reason.

 

Clear skies Markus 


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#9 SeattleScott

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Posted 06 June 2020 - 09:54 AM

The lenses are ground by machines these days even for top brands. Today, “hand figured” refractor optics really just means after the normal process, a person took the lens and evaluated it thoroughly, maybe touch up a zone (with a grinding machine) and/or optimized the spacing and rotation of the lens. I don’t get the impression there is a ton of manual labor involved these days. That being said, to get a smoother polish, it requires more time in the grinding machine. If you leave each lens in for twice as long you can only produce half as many scopes. So there is a very real cost just in machine time to get a precise optical figure with smooth polish.

Maybe the easiest comparison would be a SV Access compared to a Vixen ED103S. The Access used to cost $1,100. The ED103S was $1,800. You can argue which one is better build quality, but I suspect most would give the edge to the SV. So $700 less the cost of a sliding dew shield or something. Another way to look at it is the limited run of Access scopes with premium optics. I think there was a surcharge of $500-600 to upgrade to a premium optical figure for a 4” model. Similar to $700 with an adjustment for build quality. So Vixen might have an extra $100 or so built into their price for Japanese labor rates or brand recognition.

Scott
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#10 db2005

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Posted 06 June 2020 - 09:55 AM

That is a good point. And the higher labour costs would mean it makes sense to make better optics so that a higher selling price would be accepted by the market.

 

Still, I do wonder how much effort goes into the lenses.



#11 Echolight

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Posted 06 June 2020 - 10:38 AM

I think we pay mostly for the limited market causing astronomical markup of products.

 

I mean really, FIFTY-FIVE BUCKS for a 2x11x3/8 piece of aluminum!

https://www.highpoin...-11-long-vdup11



#12 db2005

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Posted 06 June 2020 - 10:56 AM

I think we pay mostly for the limited market causing astronomical markup of products.

 

I mean really, FIFTY-FIVE BUCKS for a 2x11x3/8 piece of aluminum!

https://www.highpoin...-11-long-vdup11

Good one, and a fine point in case. Yet I don't believe this is universally true; on low-value items retailers need a higher markup to pay for handling the item. But for more expensive items the markup will likely be much lower. While arguably expensive by most standards, I don't think premium products are generally over-priced, as you tend to get what you pay for.

 

And I doubt the typical profit margin on high-end products is stellar (pun intended). If they were, some clever retailer or manufacturer would immediately gobble up the market by under-bidding other retailers by a few hundred $$$ on premium units. But we don't seem to see that happening much. It seems to me that most of the global price differences in premium brands can be explained by geography (shipping costs), differences in tarriffs, sales taxes and different warranties.

 

But amateur astronomy is a niche market, premium telescopes even more so, which would require higher markups than, say, consumer electronics and dairy products, to be profitable.


Edited by db2005, 06 June 2020 - 10:57 AM.


#13 Jon Isaacs

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Posted 06 June 2020 - 11:00 AM

There is probably some truth in that... but anyone familiar with Zemax or similar raytracing software can "theoretically" reverse-engineer premium optics from specs and may even convince themselves that that they could build their own. But actually figuring and polishing the surfaces to the desired figure and smoothness would seem to be another thing entirely, involving using actual tools and knowing the quirks of how optical glass and lens-making tools behave during processing, etc.

 

I am pretty convinced that more actual work is being done on premium optics vs. run-of-the-mill optics. Otherwise run-of-the-mill optics would be just as good as the premium counterparts.

 

Roland Christen once wrote that he could design 100 apos a day. He's always been free with his designs. 

 

He said, what's important is the execution of the design, that's what you pay for.  

 

In my opinion, if someone is claiming proprietary magic designs doublets and triplets, it's just hype.

 

Jon


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#14 Echolight

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Posted 06 June 2020 - 11:12 AM

Good one, and a fine point in case. Yet I don't believe this is universally true; on low-value items retailers need a higher markup to pay for handling the item. But for more expensive items the markup will likely be much lower. While arguably expensive by most standards, I don't think premium products are generally over-priced, as you tend to get what you pay for.

 

And I doubt the typical profit margin on high-end products is stellar (pun intended). If they were, some clever retailer or manufacturer would immediately gobble up the market by under-bidding other retailers by a few hundred $$$ on premium units. But we don't seem to see that happening much. It seems to me that most of the global price differences in premium brands can be explained by geography (shipping costs), differences in tarriffs, sales taxes and different warranties.

 

But amateur astronomy is a niche market, premium telescopes even more so, which would require higher markups than, say, consumer electronics and dairy products, to be profitable.

If they produced and sold 100x what they do, then surely they wouldn't have to make as much profit on each one.


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#15 OldManSky

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Posted 06 June 2020 - 11:26 AM

I would add an opinion that the experienced, "master" lens-figurers at (say) Takahashi are not only better at evaluating and figuring lenses than lower-paid, less-experienced workers elsewhere, they're also *faster* at doing so.  Which might offset some of their higher salaries, but probably not all of it.  

It certainly takes more time to critically and thoroughly evaluate a lens set, and hand-figure it to a minimum standard, than it does to run a machine evaluation and do some quick touch-ups.  But I'm also convinced it doesn't take 4x as long, or cost 4x as much. And the more experienced your staff is, the more efficient they can be at producing high-standard optics. The higher standards allow charging a higher "premium" price, whether that's reflected in the cost to manufacture or not.  It's the same with any "premium" product, not just telescope lenses...


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#16 StarWolf57

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Posted 06 June 2020 - 11:50 AM

It really comes down to cost vs performance and the curve gets steep at the big end. If you want a telescope whose performance is in the 80th percentile, you can probably get something that works well at a reasonable price. You want to be in the 99th percentile? You better be ready to shell out big $$$ to get there.


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#17 Jon Isaacs

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Posted 06 June 2020 - 12:21 PM

Optical quality and cost:

 

For a research project we needed an Etalon for Brillouin spectroscopy that was better than lambda/400. It was less than 1"x1".  It cost $4000.

 

Jon


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#18 Supernova74

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Posted 06 June 2020 - 12:31 PM

Much of the price we pay for high-quality refractors is due to optical quality, i.e. the quality of lens figure and polish. Of course, the cost of glass/fluorite blanks also depends on material quality. It is my understanding, however, that we pay more for the workmanship going into the optical surface than the material they are made of. Optical quality doesn't occur by accident but by quality workmanship. Experience at the eyepiece also confirms that optical quality is a real thing, and more expensive optics perform better than inexpensive optics.

 

But I wonder how long time and how much effort it actually takes to manufacture a premium-quality optic, say a Tak FC-100 versus a more common ”run-of-the-mill” optic (say, something like a ED100).

 

In other words, what is the manufacturing costs of optical quality? Supposing a given premium optic is priced at 3-4x more than a run-of-the-mill optic, would that also imply that the premium optic is 3-4x as expensive to make, because of the additional attention to lens figure and polish? And is the additional cost incurred because of extra time for hand-finishing high-end optics, or is the cost simply incurred by needing machines to work longer and slower on the lenses for a better finish?

 

Can anyone offer some reliable information about that? Any insights as to the cost-breakdown of making high-end optics?

 

Thanks,

Daniel

Um!? How long is a piece of string optical quality costs what your only prepared to pay for it 


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#19 skybsd

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Posted 06 June 2020 - 12:59 PM

Hello Daniel, 

 

...

 

Can anyone offer some reliable information about that? Any insights as to the cost-breakdown of making high-end optics?

 

Thanks,

Daniel

So the answer to your actual question is: yes - and you can secure all the insights you desire by simply contacting any of the manufacturers whose products fall within your definition of "high-end optics" and just asking them.., The absolute worse thing that can happen would be their declining to answer. 

 

That is of course, if your objective is to obtain actual FACTS .., as I'm not sure (largely unqualified) responses from random strangers on an (albeit very popular) Internet forum is the way to go here.., 

 

Hope this helps.., and good luck.., 

 

Best.., 

 

skybsd 


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#20 Spikey131

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Posted 06 June 2020 - 01:40 PM

Talk to any sales person in manufacturing or a service industry.  They will tell you that the devil is all in the details.  It is less secrets and design and more execution and customer service.


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#21 gitane71

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Posted 06 June 2020 - 02:14 PM

It is known Galileo's scopes had 2 lenses.

It is known that Campini made better optics

It is known that Newton was able to make scopes without chromatic aberration

It is known Cassegrains weren't made earlier because they didn't know how to achieve the accuracy for the needed curves.

It is known that Dolland made achromats with at least 2 lenses in the objective.

It is known that Herschel made long reflectors, but much shorter than the long single lens refractors.

It is known Clairaut, Littrow, then Fraunhofer developed refractor designs that improved Dollands achromats.  

It is known Foucault improved 'quality control' with his tester.  

More designs and tests followed and I would think all of that continues today.  

There are designs that are very 'forgiving' and there are designs that Require High quality control.

I ground my first mirror in a dirt floored garage.  I didn't understand the Foucault test.

I've been told you CAN'T make a refractor without using test plates.  Many have written that you NEED a lathe 

to make a refractor.  They are generally assumed to be Requirements.  So, advancements not just in glass, but in tooling, 

testing, and the education involved in all of that add up. 

And they don't do it with a dirt floored building or in 45 degree weather.

I would assume things are so complex that as in other business, there is still 'scrap' and the scrap no longer involves 

the bottoms of pie plates or Coke bottles.  

I think some things have become so 'routine' that a 4" achromat, a 'great' scope in the 60's is now often shunned.  

I've heard from someone in the industry that grade B BK7 is better than many other grade A glasses, but it isn't 

BK7 that is the 'magic' in most apos.   

Maybe too 'simply',  I think it is a big 'overhead', an entire 'culture' that has become complex.


Edited by gitane71, 06 June 2020 - 10:06 PM.

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#22 Rollo

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Posted 08 June 2020 - 10:42 PM

Well, being a trades person myself,, I would have to guess and say this,,, there are probably very few glass polishers that are capable of making super high quality lens or mirrors,, period.   It would take many years of practice and a considerable amount of God given talent to become one.  So,, maybe that might be a big factor in the equation.   In other words,, just finding someone who is capable of such feats may not be easy to do.  


Edited by Rollo, 08 June 2020 - 10:53 PM.

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#23 LDW47

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Posted 09 June 2020 - 10:19 AM

Roland Christen once wrote that he could design 100 apos a day. He's always been free with his designs. 

 

He said, what's important is the execution of the design, that's what you pay for.  

 

In my opinion, if someone is claiming proprietary magic designs doublets and triplets, it's just hype.

 

Jon

The Chinese are doing pretty darn good with the hype these days vs the $ you pay ! As a great poet once said ‘ the times they are a changin ‘, even with scope glass and their design / manufacture !  Clear changin skize !  PS:  And year over year they appear to be getting better yet only charging the same, thats scary and the selection increases !


Edited by LDW47, 09 June 2020 - 10:23 AM.


#24 LDW47

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Posted 09 June 2020 - 10:26 AM

Well, being a trades person myself,, I would have to guess and say this,,, there are probably very few glass polishers that are capable of making super high quality lens or mirrors,, period.   It would take many years of practice and a considerable amount of God given talent to become one.  So,, maybe that might be a big factor in the equation.   In other words,, just finding someone who is capable of such feats may not be easy to do.  

 

Optical quality and cost:

 

For a research project we needed an Etalon for Brillouin spectroscopy that was better than lambda/400. It was less than 1"x1".  It cost $4000.

 

Jon

Yes but in research, in the building of prototypes, in the first time trials etc. costs are always highly inflated its the nature of the beast ! What you are talking is no different, its nothing new !  Clear optical skiys !


Edited by LDW47, 09 June 2020 - 10:27 AM.


#25 Jon Isaacs

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Posted 09 June 2020 - 10:59 AM

Yes but in research, in the building of prototypes, in the first time trials etc. costs are always highly inflated its the nature of the beast ! What you are talking is no different, its nothing new !  Clear optical skiys !

 

This was just the Etalon. It was manufactured by a small firm whose speciality is making high precision optics. This was not research, it was not a prototype, it was just a very high quality piece of glass.

 

My point is that extremely accurate work is possible but it is very expensive. And in that spec, there's no room for error. With a telescope optic, no one really knows how good it is.

 

In this case, the quality of the optic is immediately apparent in the test setup. Lambda/400 was a worst case, that or better.

 

Jon




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