Seeking Lens Element Specifications

[bayernfan]

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Are there known resources available that specify the details of the optical elements in classic Leitz/Leica lenses?  I would need: lens curvature, thickness, index of refraction, abbe number, and z-axis coordinates. 

I suppose I could dismantle a lens to physically measure all or some of these values, but I had hoped a quick reference was available.

Big thank you for any assistance.

 

[adan]

There is a blog (in Italian) that gives some of that information for some lenses.

I stumble into it googling lens diagrams sometimes, but cannot ID it right now (perhaps someone else can).

Edited June 19, 2020 by adan

[bayernfan]

15 minutes ago, adan said:

There is a blog (in Italian) that gives some of that information for some lenses.

I stumble into it googling lens diagrams sometimes, but cannot ID it right now (perhaps someone else can).

would this happen to be the website:

http://www.marcocavina.com/articoli_fotografici/50mm_Leica_a_telemetro/00_pag.htm

[Jeff S]

This might provide a bit...

https://lhsa.org/2018/09/rare-earth-glass-leica-lenses-a-quick-and-quirky-overview/
 

You might contact LHSA for more, or for possible sourcing guidance.

I don’t know how much info might be included , if any, in various books/documents from Erwin Puts.

Jeff

Edited June 20, 2020 by Jeff S

[adan]

5 hours ago, bayernfan said:

would this happen to be the website:

http://www.marcocavina.com/articoli_fotografici/50mm_Leica_a_telemetro/00_pag.htm

That is one part - here are some others. Seems to be a strangely-constructed site (or sites). The first link has an index to quite a few lens analyses (not all Leica).

http://www.marcocavina.com/articoli_tecnici_fotografici.htm

http://www.marcocavina.com/articoli_fotografici/Leica_35_1,4_aspherical/00_pag.htm

As a fan of the 1980 21 Elmarit, I like this progression of how an aerial lens and a 25mm f/2.8 prototype morphed and changed to get to the final 21mm design.

http://www.marcocavina.com/articoli_fotografici/Leica_M_21mm_2,8/00_pag.htm

Edited June 20, 2020 by adan

[Erato]

FYR.

Erwin Puts

-- Leica Compendium by Erwin Puts

-- Leica Chronicle by Erwin Puts

And if you're looking for more reviews, Thorsten von Overgaard and Leicaphilia is time-worthy.

 

Other resources with optical design infographic are also valuable for further reading...

https://kenrockwell.com/leica/lens-reviews.htm

Ken's review, you may tapping into link for targeted lens. Sometimes the optical design infographic also included.

 

https://www.oldlens.com/index.htm

Copyright (c) by oldlens.com All Rights Reserved. Comes with the optical design infographic and small size test shots.

 

 

Edited June 20, 2020 by Erato

[bayernfan]

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3 hours ago, adan said:

That is one part - here are some others. Seems to be a strangely-constructed site (or sites). The first link has an index to quite a few lens analyses (not all Leica).

http://www.marcocavina.com/articoli_tecnici_fotografici.htm

http://www.marcocavina.com/articoli_fotografici/Leica_35_1,4_aspherical/00_pag.htm

As a fan of the 1980 21 Elmarit, I like this progression of how an aerial lens and a 25mm f/2.8 prototype morphed and changed to get to the final 21mm design.

http://www.marcocavina.com/articoli_fotografici/Leica_M_21mm_2,8/00_pag.htm

I wonder if there is a database out there containing the patent paperwork for all of these older designs. 

The Marco Cavino site is definitely a great resource for refractive indices and abbe (dispersion) numbers.  Not much in the way of geometric measurements, but I suppose I could calculate those by scale if I can get the diameter of one of the elements.

Edited June 20, 2020 by bayernfan

[ianman]

One of the best resources I know of is over on the summilux.net forum

http://www.summilux.net/documents/index.php

[bayernfan]

Just a quick update, I found many of the patented designs I was seeking (with design parameters) in some books that cover optical design theory.  If anyone is interested, I can point them in the right direction.

[pgk]

It might also be worth looking for some glass manufacturer's catalogues from relevant periods, as glass formulations should be listed and I aware that they change and some become unavailable over time.

[JPerezZab]

On 6/22/2020 at 1:07 AM, bayernfan said:

Just a quick update, I found many of the patented designs I was seeking (with design parameters) in some books that cover optical design theory.  If anyone is interested, I can point them in the right direction.

That´s great. I am trying to find a replacement (or at least, something similar from another manufacturer) of a front element for a Summaron f3.5cm 3.5. Is it included in the book you mentioned? 

Edited January 31, 2021 by JPerezZab