Hello from Europe

[Lorac1951]

Hey, everybody,
I'm a retired French-speaking Belgian photographer in Portugal. Sometimes I look for notions of a bygone era. I hope to find old technical specialists here. Are there learned ancestors among you?
See you soon.

 

[M.A.Longmore]

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Welcome Home, Lorac1951 !

~ Ron
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[Lorac1951]

If this is not the appropriate place to ask the question, where and how can I initiate a new thread ?
Who can explain to me the use of the graduated scale located above the APO-Ronar lens mount ?
https://oneofmanycameras.com/products/rodenstock-890mm-f16-apo-ronar-for-ulf

 

[David Allen]

The APO-Ronar series of process lenses were optimised for 1:1 reproduction. The scale that can be seen in your photograph is to help calculating effective apertures when doing close-up photography. How it actually works has long slipped out of my memory.

Bests,

David.

 

[AgX]

David, basically you are right. But to me the figures make no sense... For instance at 2x extension resp. 2x scale the aperture must be opened 2 stops etc.

I do not see such at those diagrams, irrespective whether I read the figures as distance units or percentages.

 

[mohmad khatab]

A Belgian who speaks French, he will definitely be fully familiar with the Flemish language and since he lives in Portugal it is natural for him to learn Portuguese and to write in English. ,, Very great.

This is the international analog community, and it contains the best and finest experts on the planet.
It is a cooperative society based on knowledge, cooperation and the sharing of science, knowledge, arts and culture among all.
The world is not always a forest as you think it says. The world in this society is based on love, cooperation and brotherhood among members.
- I am really standing before your message and wondering,
Is it a welcome and loving message? Or does it contain some arrogance and belittling others?
What do you mean when you say (Are there learned ancestors among you?)
!!!!!
In fact, the wording of this question seems somewhat insulting and uncomfortable - you seem to be a really suspicious man.
Be polite when you talk, we are not your employees.
- Who are you, - Hey, old man - What do you want?
If you have an inquiry ,,
You can offer your inquiry in a courteous and gentle manner.
The community does not offer paid counseling until you speak that faint tone as if you were a customer.

 

[Lorac1951]

Dear sir mohmad khatab
I think you need an explanation.

1) Acknowledgments:

Two relevant answers to my first question came quickly from the goodwill of two well-meaning people. Thanks to David Allen and thanks to AgX for your courteous collaboration.

2) Explanations:

Not all French-speaking Belgians have knowledge of the second national language: Dutch (Flemish is a dialect).

My practice of English is insufficient to write in correct English, so I write in French in the left window of the translator. After which, I copy the English translation in the message of your forum.

When I wrote: "Are there learned ancestors among you?", my intention was to ask if there are among you people who by their experience are sufficiently experienced to know the answer to what I am looking for.

I hope you enjoy the way I compose my sentences.

Best regards.

 

[Sirius Glass]

Welcome to APUG Photrio!!