18 replies to this topic

[Stew44]

If you jump right to the Classics forum each day you may miss the wonderful article by PawPaw (Don Chatfield) about Goto's response to Tak's apo and semi-apo offerings released in 1972.  Took them a couple years but they didn't miss a single base on the doublet and triplet offerings they provided for glasses and fluorite available at the time for buyer consideration in 1976.  A good read.

 

 

[Dave Trott]

Many of the telescopes we talk about here in this forum are Japanese (or Japanese imports). The big names in Japan for many years during the early twentieth century were Nippon Kogaku (Nikon) and Goto Kogaku. The little upstart Takahashi did not come along until the 1960's. At first the big names did not seem to recognize the threat from this newcomer to the market. In his article, Don Chatfield presents the substantial evidence that in the 1970’s Goto mounted a mind boggling response to Takahashi.

 

In his astoundingly detailed and complete analysis, Don has documented the seemingly overwhelming reaction of Goto.  For those of you who are interested in these battles between mid-century telescope manufacturing giants, this article is a must-read. It really gives you a deep sense of the situation.  Many of us like to imagine we were there when all these fine telescopes were first available on the market. What was it like? It must have been an exciting time in Japan to see these behemoths fighting tooth and claw for the attention of the amateur telescope buyers.

 

What fun!

 

Here's a link to Don's Article: https://www.cloudyni...-for-1976-r3393

Edited by Dave Trott, 01 July 2023 - 11:50 AM.

[PawPaw]

Thanks to Dave and Stew or I would not have attempted to go down this rabbit hole!  They both helped not only with advice but content.

 

Some new information has come to light regarding when Goto started working on their Apochromat designs.  There is an ad by Goto in the 1976.9 Tenmon catalog states they started working and testing a new type of glass from Schott starting in 1973 but eventually chose  Ohara glass.  You may have to save the image and  enlarge it for easier reading.  

 

 

 

Don

Attached Thumbnails

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Edited by PawPaw, 02 July 2023 - 07:11 AM.

[Bomber Bob]

Great Article, Don!  

 

I wonder... Are the GOTO S-APO triplets and/or Fluorite Doublets subject to the same Flint Hazing seen with Takahashi versions?  Ditto for the Canon, Pentax, & Mizar objectives.  I see so few of these, that I can't make a determination.

[deSitter]

Many of the telescopes we talk about here in this forum are Japanese (or Japanese imports). The big names in Japan for many years during the early twentieth century were Nippon Kogaku (Nikon) and Goto Kogaku. The little upstart Takahashi did not come along until the 1960's. At first the big names did not seem to recognize the threat from this newcomer to the market. In his article, Don Chatfield presents the substantial evidence that in the 1970’s Goto mounted a mind boggling response to Takahashi.

 

In his astoundingly detailed and complete analysis, Don has documented the seemingly overwhelming reaction of Goto.  For those of you who are interested in these battles between mid-century telescope manufacturing giants, this article is a must-read. It really gives you a deep sense of the situation.  Many of us like to imagine we were there when all these fine telescopes were first available on the market. What was it like? It must have been an exciting time in Japan to see these behemoths fighting tooth and claw for the attention of the amateur telescope buyers.

 

What fun!

 

Here's a link to Don's Article: https://www.cloudyni...-for-1976-r3393

What I find interesting is that the background for all this is the explicit jump-start of the Japanese optics industry by the American occupiers in the immediate post-war period. MacArthur wanted his soldiers to have something to spend money on other than girls and saki and card games. And the Japanese were already using Zeiss as a model. Although Nikon goes back to the early 20th century, they didn't really start making noise until the post-war period. This was helped by trade deals explicitly favorable to Japanese exporters, and soon 80% or more of their market was in exports vs. domestic sales.

 

-drl

[PawPaw]

Great Article, Don!  

 

I wonder... Are the GOTO S-APO triplets and/or Fluorite Doublets subject to the same Flint Hazing seen with Takahashi versions?  Ditto for the Canon, Pentax, & Mizar objectives.  I see so few of these, that I can't make a determination.

Thanks I enjoyed the research and connecting with our Japanese friends.  

 

Great question.......I know of one Super-APO fluorite that came up for auction in the last few years. It did not have hazing.   I think there was a reason Goto did not pursue more Fluorite production.  The reason is conjecture,  but I believe Goto wanted the APO's they designed to be manufactured not only for the amateur market  but  for professional use as well.  IE:  20-25CM. 

 

As for the non-Fluorite I know of one Super-APO triplet sold recently with no hazing.  The 1977 triplet-type standard-APO I own is almost  pristine besides some dust.  

 

We believe the Suda observatory telescope is a 20cm  Super-APO triplet.  We hope to answer that definitively in the near future.

Edited by PawPaw, 02 July 2023 - 09:44 AM.

[sdedalus83]

I think there was a reason Goto did not pursue more Fluorite production.  The reason is conjecture,  but I believe Goto wanted the APO's they designed to be manufactured not only for the amateur market  but  for professional use as well.  IE:  20-25CM. 

I wonder if Canon just stopped selling blanks to other manufacturers. IIRC from things I’ve read about TEC, fluorite is easier to make in large diameters than ED glass.

[PawPaw]

I wonder if Canon just stopped selling blanks to other manufacturers. IIRC from things I’ve read about TEC, fluorite is easier to make in large diameters than ED glass.

You may well be right.   

 

Keep in mind this was the 1970's.  At the time I think polishing the Fluorite was the biggest hurdle and the larger an objective is the difficulty in polishing increases.  

 

Again all conjecture on my part on why Goto did not pursue Fluorite and chose ED glass instead.

Edited by PawPaw, 02 July 2023 - 11:00 AM.

[Terra Nova]

Great job Don! A comprehensive, and most informative bit of research. I enjoyed it and learned a lot.

[CHASLX200]

Thanks to Dave and Stew or I would not have attempted to go down this rabbit hole!  They both helped not only with advice but content.

 

Some new information has come to light regarding when Goto started working on their Apochromat designs.  There is an ad by Goto in the 1976.9 Tenmon catalog states they started working and testing a new type of glass from Schott starting in 1973 but eventually chose  Ohara glass.  You may have to save the image and  enlarge it for easier reading.  

 

 

 

Don

Love to have that big scope but would need 200k and a much bigger boat to keep it.

[Stew44]

Nikon was making cameras (and camera lenses) in the time from the twenties through the war years and after.  They likely made all the lenses for Goto during that time frame.  I talked about Nikon's Yoshida in an earlier thread as really a chief designer during that period establishing the standard designs that many amateurs in Japan quote today.  Goto went a lot further with independent innovative designs like the blue window glass school telescope design.  Don's article in Tenmon shows they looked at over 50 designs to wind up with the nine they presented in 1976.  It also says they developed in house the techniques to make these lenses with fluorite and ED glass as they were already making optics in house for the planetarium projectors they were focused on.

[RichA]

Many of the telescopes we talk about here in this forum are Japanese (or Japanese imports). The big names in Japan for many years during the early twentieth century were Nippon Kogaku (Nikon) and Goto Kogaku. The little upstart Takahashi did not come along until the 1960's. At first the big names did not seem to recognize the threat from this newcomer to the market. In his article, Don Chatfield presents the substantial evidence that in the 1970’s Goto mounted a mind boggling response to Takahashi.

 

In his astoundingly detailed and complete analysis, Don has documented the seemingly overwhelming reaction of Goto.  For those of you who are interested in these battles between mid-century telescope manufacturing giants, this article is a must-read. It really gives you a deep sense of the situation.  Many of us like to imagine we were there when all these fine telescopes were first available on the market. What was it like? It must have been an exciting time in Japan to see these behemoths fighting tooth and claw for the attention of the amateur telescope buyers.

 

What fun!

 

Here's a link to Don's Article: https://www.cloudyni...-for-1976-r3393

$10,000 equivalent dollars for a 90mm fluorite in 1977 it's no wonder the market didn't go for it.  Also, inflationary pressures all during that decade must have made it all the harder.

[RichA]

You may well be right.   

 

Keep in mind this was the 1970's.  At the time I think polishing the Fluorite was the biggest hurdle and the larger an objective is the difficulty in polishing increases.  

 

Again all conjecture on my part on why Goto did not pursue Fluorite and chose ED glass instead.

Canon did use fluorite for some of its lenses even then, (specialty still lenses and large TV broadcast lenses) but I'm not sure they'd have maxed out the capacity of Optron so you'd have expected them to look for other markets.  Today according to "some" you can't get decent ED glass over 5 inches in diameter today whereas fluorite is presumably strain and straie free.

[Stew44]

Love to have that big scope but would need 200k and a much bigger boat to keep it.

While these things look magnificent and huge, we have to remember that materials and especially mount capability have improved even during this early Apo time.  I was at Astrofest in the late 90's and saw the 8" Astro-Physics apo that Allan and Sue French had set up.  Large telescope for sure, but even then, portable, and mount available to adequately support in the field.  Roland had his 10" Mak set up and again when you compare the large Astro-Physics mount supporting that in the field to the Questar 12" Mak OTA and mount that graced so many Sky and Telescope advertisements, it's an entirely different game.

 

These public observatories do still have a place in our hearts, and observing opportunities with them are wonderful.  Here in Denver the Chamberlin observatory sports a 20" Clark and it is a treat to visit such a fine specimen of the master's art.

 

Edited by Stew44, 03 July 2023 - 07:09 AM.

[Dave Trott]

$10,000 equivalent dollars for a 90mm fluorite in 1977 it's no wonder the market didn't go for it.  Also, inflationary pressures all during that decade must have made it all the harder.

I suspect much of the reason for Takahashi's market strength during the 70's was the price point. Their scopes seem to have been consistently much less expensive than Goto and Nikon for roughly equivalent telescopes. 

[RichA]

I suspect much of the reason for Takahashi's market strength during the 70's was the price point. Their scopes seem to have been consistently much less expensive than Goto and Nikon for roughly equivalent telescopes. 

Yes, it's interesting to think about Takahashi being "economical."

[Stew44]

I've had the opportunity to use and evaluate a couple of Dave Trott's Tak telescopes from the early years.  These are amazingly well built and serious competitors for Goto, not to mention Unitron as well.  I believe Tak had already acquired the excellent sand casting skills they use today back in the 70's.  Nice stuff (although no MC on the eyepieces or lenses so coatings yet to come).  Lenses are pretty much perfectly figured.  So yes, quite economical.

[Mike W]

Mabe a good time to revive this thread:

https://www.bing.com...JhY3Rvci8&ntb=1

[PawPaw]

Mike.....Thanks for the link again.  I have read through your thread in the past and I think it is a perfect fit here.  

 

Looks like  we may have some new info on the missing Suda telescope soon.  

 

Don