Refractor Developments In The Last 40 Years....

[Ian McCallum]

Is there an online resource documenting refractor developments over the last 40 years, preferably without too much technical jargon?🤔

[vlaiv]

I don't know resource that will do such long span, but you might want to look at this website:

https://www.scopereviews.com/list.html

Look under refractors.

It contains reviews that are 20+ years old, and I guess that some of those scopes were in the market longer than that. In any case, Ed often talks about scopes from even earlier days in his reviews so it is worth reading them if you want to get the sense of what was common during any particular period of time and how much it costed.

As far as optics goes - many things have been developed long since and just few things changed refractor landscape in past few decades:

1. Availability and drop in price of exotic glasses as well as high quality coatings

2. Computer aided design and more sophisticated testing

3. Cheaper manufacturing due to mass production and utilization of machines

[Ian McCallum]

If that's Ed Ting, I subscribe to his YouTube channel.😉

[vlaiv]

10 minutes ago, Ian McCallum said:

If that's Ed Ting, I subscribe to his YouTube channel.😉

It is. YouTube channel is recent development. He's been reviewing scopes for much longer time.

[plyscope]

Holger Merlitz has some Astro Physics historical catalogues from the 80's and 90's.

 

http://www.holgermerlitz.de/A-P_database/A-P_catalogs.html

[plyscope]

I found this on Zeiss history;

http://www.company7.com/zeiss/history.html

[plyscope]

Here is some insight into Takahashi Fluorite triplets and doublets.

http://www.astrosurf.com/ilizaso/Takahashi FCT-100/FCT.htm

http://www.astrosurf.com/ilizaso/Takahashi FS-102/FS.htm

[John]

I've been using refractors for the past 40 years - what do you want to know ?

Joking apart, this is a good resource:

http://www.astronomynow.com/books/Choosing and Using a Refracting Telescope.html

 

 

[plyscope]

These new APQ Jena refractors may be the current state of the art for refractor development.

https://apq.de/en/

 

In America the latest development at least for visual observers is the Agema doublets.

https://www.agemaoptics.com/

[Alan White]

Interesting links, but for me way above and beyond my means.

Wonder who will be brave enough to buy number 001? 

 

Edited October 24, 2021 by Alan White

[Ian McCallum]

I'm interested in this because of the ScopeTech range and where the fascination and development of long focal length refractors came from...

[Franklin]

Traditional Achromatic refractors suffer from chromatic aberation, where the different frequencies of light are focused at slightly different points. Making the focal length of the lens longer helps to reduce this aberation. Before the invention of the Crown and Flint doublet lens, which also reduces this CA, they made what were called Ariel telescopes which had focal lengths of 50+ft. The objective was positioned on a tall mast and the eyepiece was held at the end of a taught piece of rope! So glad they developed the modern lens designs.

Edited October 24, 2021 by Franklin
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