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New Chromacor - RayCorr

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#1 Psion

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Posted 20 July 2018 - 08:45 AM

Will you buy RayCorr (new version of the Chromacor)? A lot of people say, today is a nonsense, yes I agree, but only for a small telescope. For the achromatic refractor from 7" is a very good idea, because 7" ED or APO is too expensive, I think.



#2 Richard Whalen

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Posted 20 July 2018 - 10:00 AM

Do you have a link to it? I might depending on performance and price.


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#3 JonH

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Posted 20 July 2018 - 10:09 AM

I would love one and was very excited about the proposed Istar version but it seemed to melt away into the mist. I guess the glass must have been prohibitively expensive. If you do know of someone selling something that is actually in production, please do post a link. I looked briefly on line just now but couldn't see anything.

 

Cheers

 

Jon



#4 Psion

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Posted 20 July 2018 - 10:46 AM

I discussed RayCorr many times with my friend Ales from iStar Optical. He didn't believe, people will buy RayCorr for example 1400 USD for big refractors. iStar is selling achromatic refractor 8" F6 now, RayCorr is good for such a telescope like this or for a telescope from 8" to 12" from D&G and etc.. My question is, produce RayCorr or not? 



#5 Jimmy462

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Posted 20 July 2018 - 10:56 AM

Will you buy RayCorr (new version of the Chromacor)? A lot of people say, today is a nonsense, yes I agree, but only for a small telescope. For the achromatic refractor from 7" is a very good idea, because 7" ED or APO is too expensive, I think.

Hi Psion,

 

I would think there is a bigger pool of 6- or 5-inch achromat owners to "market to" along side 7-inchers. For me, a 6-inch f/15 or f/12 Fraunhofer doublet with a Chromacorr would seem like the perfect refractor. Your thoughts or considerations on such a corrector for a beast of this size?

 

:)

Jimmy G



#6 Psion

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Posted 20 July 2018 - 11:08 AM

It isn't a problem make RayCorr for the telescope like this, but a lot of people will buy rather a new Skywatcher ED 150/1200 for 2000 USD, than 6-inch Fraunhofer doublet + RayCorr.


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#7 jrbarnett

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Posted 20 July 2018 - 11:15 AM

I discussed RayCorr many times with my friend Ales from iStar Optical. He didn't believe, people will buy RayCorr for example 1400 USD for big refractors. iStar is selling achromatic refractor 8" F6 now, RayCorr is good for such a telescope like this or for a telescope from 8" to 12" from D&G and etc.. My question is, produce RayCorr or not? 

Here's the Raycorr problem.  It was talked about (a lot) for a very long time, during which time Istar was selling quite a few big achromats for which such a device would have been ideal.  No device materialized at that time.  Now the market for big achromats seems to be drying up a bit.  The existence of a Raycorr now *might* resuscitate that niche, but I think you need a coexistence of the device and available large achromat OTAs for that renewal to happen. 

 

You also have 6" ED doublets coming in at 1670 Euros and likely to fall below that in the not too distant future.  Sure they aren't up to the build of Istar's beefy scopes, but buyers are price sensitive.  You don't need a Raycorr for those.  So it looks like the addressable market for the Raycorr is actually trending smaller rather than larger.  It would have been a nice "value add" when Istar was selling big achromats in volume and driven more sales, but if the model now is as a lens seller with ATMers and institutions as its addressable market, Ales is probably right.  Not a huge market for $1400 Raycorrs with no one selling many new telescopes that need one.

 

These are small niche markets that tend to change quickly.  Timing is everything.  My fear is that the window where this would have been successful may not have closed, but is probably closing.

 

How many big achromats that lack Chromacorrs does Istar think are out there (Istar's own, D&G, vintage big achromats in public institutions that do outreach, etc.)?  One approach might be to look at all of the observatories in populated areas that do public education and viewing and use grand old achromats to do that work.  Examples in the US include the US Naval Observatory, Chabot Science Center in Oakland, California, Mt. Hamilton in San Jose California, Lowell Observatory in Flagstaff, Arizona, etc.  I did see a Feathertouch focuser mounted to one of the big brass achromats at Greenwich Observatory when I visited in 2014.   

 

Could you make a break-even business with those types of customers (classic scope obervatories that do public viewing) as your baseline?  That boils down to cost and budget, and perceived value.  Will a prettier color-reduced image help them with their public outreach charter?  Do non-astronomer visitors care if they see a lot of false color on Saturn?  Very hard to tell.  But basically quantify the addressable market in each segment where the device might solve a problem, make assumptions about uptake rates in each segment (be conservative) and then back into the math to figure out whether it can be done profitably. 

 

Best,

 

Jim 


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#8 Jeff B

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Posted 20 July 2018 - 11:58 AM

With the advent of "inexpensive" 6" ED doublets, such a device is just not going to make it for that aperture and under.  The total cost of the system would be just too much at that aperture.  Sure, in that aperture, it can give you superior correction (CA and SA) over a portion of the FOV centered on axis but it will display lateral color beyond that field.  And that's just fine for the planets, double stars, globs and the moon (if you're using mono-centric eyepieces) but it is a limitation which the the ED doublet does not have to anywhere near that degree.

 

So , IMO and IME, these devices really start to become useful, and cost effective (a sufficiently small percentage of the system cost), with large, slow apertures 7" and above.  Indeed, to me, they make a whole lot of sense at apertures 8" and above and no faster than F9.  And that's exactly how I use my Chromacors.  But even then you start bumping up against other designs like the Zerochromat, so again the bigger the aperture, the more sense they make to me.

 

Technically, the best performance is gotten when the thing is matched to, or part of, a complete system design and the slower the system, the more effective the device can be on and off axis.    

 

So it's a niche market that I see divided into two basic segments, those with existing big, slow achromats and those seeking a new big, slow achromat (though with the system properly integrated into the design, I'm not sure it should still be called an achromat).   System performance is a compromise with the former (unless customized for the lens) and optimized with the later.....but still a divided market and small sized divisions at that.

 

But I'd still like to see a Raycor series and would be curious as to just how much it would cost to have a one-off unit custom made for an 11" F12 achromat.  Even at $3K-$5K USD, it would get my attention. 

 

Jeff


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#9 PETER DREW

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Posted 20 July 2018 - 12:33 PM

I have a 8.5" F12.5 achromat at our outreach facility, the CA is not enough to warrant an expensive correction system.
Visitors get so excited at seeing Saturn first time any extra halo colour just adds to the spectacle.
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#10 Jimmy462

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Posted 20 July 2018 - 12:33 PM

It isn't a problem make RayCorr for the telescope like this, but a lot of people will buy rather a new Skywatcher ED 150/1200 for 2000 USD, than 6-inch Fraunhofer doublet + RayCorr.

Hi Psion,

 

While I do agree with your assessment that it's likely that most newcomers to the 6-inch refractor market would consider the SW 150ED, my question was related to the already-embedded base of 5- and 6-inch achromats (i.e. current iStar, D&G, A. Jaegers, etc.owners) of which, I imagine, must number in the several thousands globally.

 

Manufacturing to an existing user base to solve an inherent optical aberration is pretty much what the coma-corrrector manufacturers seem to be doing quite successfully with the "fast" Newtonian/Dobsonian user base.

 

The concern about a small market for future "6-inch Fraunhofer doublet + RayCorr" actually then becomes a market bonus margin in such a venture.

 

Case in point, me...I've been exploring my options on a 6-inch refractor and am currently keeping an eye on how the new SW offerings works out. I'm also keeping an eye on the APM 150ED offerings as they've been frequently (and currently as I write this) available at a competitve price to the new SW's. And, I've been perusing the classifieds for either a full-up 6-inch f/15 scope or mounted Objective aaand I was just sniffing around the iStar web site last night looking at their 6-inch f/15 achromats.

 

So, had you been making and selling these "magic beans" all along I might well have already made a decision on an iStar achromat and been out observing already! My math would have been..."$707 for f/12-or15 doublet + $1,400 for ChromaCorr/RayCorr = $2,107 for a customizeable hand-figured 6-inch f/12-or-15 "APO" optic set with collimateable cell vs. off-the-shelf mass-produced non-collimateable market alternative?"

 

Keep us posted should you change your thinking!

 

And, yes, a "magic bean" for the iStar 180/1440 R35-S would be a super product to bring to market...well, IMHO.

 

smile.gif

Jimmy G


Edited by Jimmy462, 20 July 2018 - 12:35 PM.


#11 Jon Isaacs

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Posted 20 July 2018 - 01:01 PM

Manufacturing to an existing user base to solve an inherent optical aberration is pretty much what the coma-corrrector manufacturers seem to be doing quite successfully with the "fast" Newtonian/Dobsonian user base.

 

 

For visual use,  coma correctors range from a little more than $100 for the GSO to around $500 for the TeleVue.  Unlike the Chromacorr and presumably any other such chromic corrector,  coma correctors are not finicky and do not require careful installation and alignment.  It's one size fits all and swapping from one scope to the next is no more diffucult than swapping a Barlow. 

 

A big difference between the coma corrector and the chromatic corrector is the practical aspects . A coma corrector makes fast focal ratio , compact telescopes possible . You pay your $500 and now that 22 inch F/3.5 has the off-axis correction of a F/10 but doesn't need a ladder .

 

The use of a long focal length achromat with a chromatic corrector is quite the opposite.  A 6 inch F/15 is about 90 inches long and is much more awkward than a 6 inch F/8 and requires a much more substantial mount . A 6 inch F/15 is 90 inches long.  I'd have tie it to the roof of my minitruck.  

 

I think Jim is right , the time has passed by for another chromacorr. It's a tiny market and its only getting smaller. Valery pulled it off but Valery is someone special . I sometimes think the Chromacorr was his way of showing just what he could design and manufacture..  

 

Jon


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#12 Jimmy462

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Posted 20 July 2018 - 01:41 PM

For visual use,  coma correctors range from a little more than $100 for the GSO to around $500 for the TeleVue.  Unlike the Chromacorr and presumably any other such chromic corrector,  coma correctors are not finicky and do not require careful installation and alignment.  It's one size fits all and swapping from one scope to the next is no more diffucult than swapping a Barlow. 

 

A big difference between the coma corrector and the chromatic corrector is the practical aspects . A coma corrector makes fast focal ratio , compact telescopes possible . You pay your $500 and now that 22 inch F/3.5 has the off-axis correction of a F/10 but doesn't need a ladder .

 

The use of a long focal length achromat with a chromatic corrector is quite the opposite.  A 6 inch F/15 is about 90 inches long and is much more awkward than a 6 inch F/8 and requires a much more substantial mount . A 6 inch F/15 is 90 inches long.  I'd have tie it to the roof of my minitruck.  

 

I think Jim is right , the time has passed by for another chromacorr. It's a tiny market and its only getting smaller. Valery pulled it off but Valery is someone special . I sometimes think the Chromacorr was his way of showing just what he could design and manufacture..  

 

Jon

Hi Jon,

 

Well, in considering that the "Big 3-inch Paracorr" fetches just north of a grand I considered that $1400 for a chromatism-corrector fair-pricing if it turned out to be "all that".

 

Regarding personal size choices, yeah, a 6-inch f/12-to-15 with "APO" performance certainly made me sit up in my chair.

 

As for ship's that've sailed and those that might not have, well that's what marketing decisions are all about and you may very well be corrct. Me? I'm in favor of encouraging the niche product here as there are clearly plenty of folks bothered by chromatism as there are folks bothered by coma.

 

Alternately, should no one decide it's worth their capital to invest in such a market with their Chromacorr or RayCorr, then I would encourage them to consider open-sourcing the design so that the ATM glass-pushing community could "have at" and maybe expand- and/or improve- and/or innovate-upon the fundamentals.

 

No argument here, just a different POV.

 

:)

Jimmy G



#13 junomike

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Posted 20 July 2018 - 02:09 PM

Will you buy RayCorr (new version of the Chromacor)? A lot of people say, today is a nonsense, yes I agree, but only for a small telescope. For the achromatic refractor from 7" is a very good idea, because 7" ED or APO is too expensive, I think.

I think that for the few people  with HUGE Achromats that want the Chromacor, the used market will supply them (If they hunt diligently).


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#14 Jon Isaacs

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Posted 20 July 2018 - 02:11 PM

Well, in considering that the "Big 3-inch Paracorr" fetches just north of a grand I considered that $1400 for a chromatism-corrector fair-pricing if it turned out to be "all that".

 

 

The 3 inch Paracorr is not a visual device,  there is no visual top for it.  Chromatic Correctors are corrected on axis but not off-axis so the comparison seems to be with a 2 inch.. 

 

In any event , with a 6 inch ED refractors soon to be available for around $2000 and very good FPL-53 120 mm doublets available for ~$1500, a $1400 corrector seems like a hard sell .

 

Jon


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#15 Jeff B

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Posted 20 July 2018 - 02:36 PM

I think that for the few people  with HUGE Achromats that want the Chromacor, the used market will supply them (If they hunt diligently).

Yup, especially if the price is right.



#16 Psion

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Posted 20 July 2018 - 02:41 PM

Thank you for all your comments and ideas. We can make universal RayCorr (compromise solution) and also for one special optical design. Universal design is better for business, but the image will be worst than with special design. You have right, a market is too tiny and achromat market are getting smaller and smaller because of ED's.


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#17 jrbarnett

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Posted 20 July 2018 - 03:57 PM

Hi Jon,

 

Well, in considering that the "Big 3-inch Paracorr" fetches just north of a grand I considered that $1400 for a chromatism-corrector fair-pricing if it turned out to be "all that".

 

Regarding personal size choices, yeah, a 6-inch f/12-to-15 with "APO" performance certainly made me sit up in my chair.

 

As for ship's that've sailed and those that might not have, well that's what marketing decisions are all about and you may very well be corrct. Me? I'm in favor of encouraging the niche product here as there are clearly plenty of folks bothered by chromatism as there are folks bothered by coma.

 

Alternately, should no one decide it's worth their capital to invest in such a market with their Chromacorr or RayCorr, then I would encourage them to consider open-sourcing the design so that the ATM glass-pushing community could "have at" and maybe expand- and/or improve- and/or innovate-upon the fundamentals.

 

No argument here, just a different POV.

 

smile.gif

Jimmy G

Both you and Jon have thoughtful perspectives.

 

To me, though, it's a total addressable market problem.

 

There are many, many more big Dobs in use than big achromats today.  Dobs are on the ascendancy and the fashion is to make them bigger and by ergonomic necessity faster and therefore shorter.  That means that coma correctors have utility in a bigger installed base that is growing.  No one uses an f/3.x Dob without coma correction.

 

In big refractors the only (well not only but main) advantage of an achromat over an apochromat was cost.  The apochromat features a solution built in to a problem that the achromat has.  The achromat value prop has been same great aperture, lower price.  Any solution that increases the price of the achromatic solution (i.e., makes the achromat relatively more costly than it was relative to the APO) or any market change that reduces the cost of the available APO solutions reduces addressable market.

 

I suspect that you might find the addressable market to be an aging handful of codgers with already minted big achromats who aren't happy with the color correction.  "Aging codger" (I'm a junior member of that august organization myself) in a niche market isn't any entrepreneurs ideal customer base.  For one we're slowly dying off and not being replaced. generationally.  For another there aren't that many of us to begin with with big achromats.

 

The more I think about it, the *only* play I would investigate if I had an interest in this space is whether I could build a holistic system that combined some kind of very mild, very cheap, large special glass doublet objective with a Raycorr to permit me to offer a reasonably mountable 180mm "Raycorrmat" for $2000-4000 all in, price in that range depending on rings, focuser, etc.  In other words, you'd need to deliver a 7" refactor with comparable color correction for the same price as the 6" ED doublets readily available.  But even then you have practical issues working against you.  6" is the biggest OTA easily mountable on very cheap commercial mounts.

 

I probably wouldn't bother.  I am still waiting for my friend Valery's H-Bomb apochromats.  IStar isn't the only one to face challenges bringing new refractor technologies to market.  Bless the dreamers and innovators.  Without them we would still be using 4" f/15 achromats and 12" EQ mounted Newtonians as our "BIG" scopes.

 

- Jim      


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#18 Richard Whalen

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Posted 20 July 2018 - 05:59 PM

I sort of agree with Jim. Nobody I know of is making large (over 6") achromats anymore. From what I have seen not even D&G. Which is a shame. I guess we can hope that someone starts making 7" to 10" ED semi apos, but not holding my breath. Hate to say it, but amatuer astronomers have become spoiled. We used to think nothing of transporting and setting up large heavy scopes, I can remember the upper observing field at TSP in the early/mid 1980s. Full of very heavy, large scopes. Sure we have got older, but I still set up a 6" f12 by myself or my 5" f15. And the younger generation? Dont see many of them at star parties. Also few are around anymore that realize the goodness of a long fl refractor. I laugh when I read posts about a 6" f8 being just to big, not practical etc. Or discussions between a 4" f8 and a 130mm f7 where weight and mount are the issue. I think we have become a nation of wimps.

 

The big dob/SCTguys being the only exception. And I rarely see a C14 on a field the last 20 years. Used to be we saw fields filled with pickups and trailers, now its small sub combacts. I can remember the days when we went vehicle shopping with a tape measure to make sure the scope we wanted or used would fit inside. I guess priorities change as we get older, or perhaps us old guys did a lousy job bring up the following generations. Or maybe we are just living in the past, holding on to a world that no longer exists. Rant over, need to get another bottle of wine out of the cellar as its 100% overcast again for the last 128 days/nights out of the last 137 and its Friday.


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#19 sg80

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Posted 20 July 2018 - 08:11 PM

Start out with universal



#20 Niklo

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Posted 21 July 2018 - 05:25 AM


You also have 6" ED doublets coming in at 1670 Euros and likely to fall below that in the not too distant future.  Sure they aren't up to the build of Istar's beefy scopes, but buyers are price sensitive.  You don't need a Raycorr for those. 

 


Jim 

Hi Jim,

which 6" ED costs 1670 Euros? In Germany I haven't seen one. But your point is right. Cromacorr + Achromat should be cheaper or at least the same price like an ED of that size. There are 5" ED out that are already very cheap:

https://www.teleskop...-5--Auszug.html

So maybe at 6" it starts to get interesting or more important as upgrade for an existing achromat. If you already own an Bresser 127/1200 an upgrade to an APO like refractor would be interesting.

The main problem I see for the chromacors is the usability. If something is not 100% adjusted the performance drops ...That's at least what I heard. A friend had an 150/1200 Bresser with chromacor and he bought an APM 152/1200 which has more CA but is easier to use. No adjusting the chromacorr any more. The chromacor 1 was less problematic and a chromacorr N with better colour correction was very sensitive for any little tilt ...

Maybe the new chromacorr raycorr improved that?

Clear sky,

  Roland


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#21 Jimmy462

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Posted 21 July 2018 - 07:33 AM

Thank you for all your comments and ideas. We can make universal RayCorr (compromise solution) and also for one special optical design. Universal design is better for business, but the image will be worst than with special design. You have right, a market is too tiny and achromat market are getting smaller and smaller because of ED's.

Hi Psion,

 

After mulling this over in my mind I'll consider that providing a ChromaCorr/RayCorr style solution might not be the best approach moving forward...but what about an f/10-15 ED "APO" doublet? Would seem to solve the chromatism issues and provide the deeper focus range a longer focal length would provide, no?

 

:)



#22 Jeff B

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Posted 21 July 2018 - 11:38 AM

Hi Psion,

 

After mulling this over in my mind I'll consider that providing a ChromaCorr/RayCorr style solution might not be the best approach moving forward...but what about an f/10-15 ED "APO" doublet? Would seem to solve the chromatism issues and provide the deeper focus range a longer focal length would provide, no?

 

smile.gif

And that's quite true too.  Trouble is no one seems to really want to make one. 

 

However, if someone did make a run of say 20, 7" F10 ED doublets and kept the weight of the bare OTA under 40 pounds and cost under or around $6K USD, I bet they would sell quickly.  



#23 csrlice12

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Posted 21 July 2018 - 11:45 AM

But does a 20" f15 Clark Saegmuller need a chromacorr?



#24 Psion

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Posted 21 July 2018 - 12:42 PM

I looked trough Clark telescope 2 years ago and I can say, yes IT does.
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#25 Psion

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Posted 21 July 2018 - 12:57 PM

And that's quite true too.  Trouble is no one seems to really want to make one. 

 

However, if someone did make a run of say 20, 7" F10 ED doublets and kept the weight of the bare OTA under 40 pounds and cost under or around $6K USD, I bet they would sell quickly.  

No, but 180mm/F8 + Raycorr will be good solution :)

 

http://www.istar-opt...ic-doublet.html




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