DIY camera repairs - electronics, mechanics, optics: Interested in a camera technology thread?

This year I have decided to deepen my theoretical knowledge of camera technology in addition to the ongoing repair projects. This includes electronics, mechanics and optics.

The more you know about what you are trying to repair, the higher the chances of success

I'm particularly interested in the electromechanical SLRs with accessoires from the mid-1970s to the mid-1980s.

For example Canon A-series, Minolta X/XE/XG/XD, Nikon F3/FG/FA/FE/FM, Olympus OM-4, Leica R3 etc.

I am supplied with specialist literature on these topics, my general knowledge of them is acceptable to good and I would like to do this not alone, but together with all those who are interested. Regardless of whether they do DIY repairs or are enthusiastic about camera technology on their own.

My question is whether there is interest here. I would open a thread where we can exchange information and experiences.

The aim is to deepen the knowledge and integrate it into repair practice. So it shouldn't be a purely theoretical discussion

Admittedly, electronics, mechanics and optics are not the easiest topics, but they are essential if you want to understand more about these cameras. It's easier to deal with it together

To get started on the topic, I'm currently reading what is probably the best-known book on the subject:

Norman Goldberg, The Dark Side of the Lens


The book was published in 1992 and therefore perfectly covers the state of technology at the time, but also offers fundamental, timeless knowledge.

This is an excellent basis for everything else.

Andreas Thaler said:

To get started on the topic, I'm currently reading what is probably the best-known book on the subject:

Norman Goldberg, The Darkside of the Lens

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Let me first say that I've read some of your repair articles and think that you've done a great job. Although I've never seriously gotten into the repair myself. (My personal mechanical work, to a fairly serious extent, has mainly been into cars.)

My normal working life has been full-time in photography although a "temporary excursion" into lab work ended up being more interesting and challenging than pure shooting. So it wasn't that temporary after all. Along those lines I got a copy of this book when it first came out (any book Norman Goldberg wrote, I had to have). I think it's a great book. But something that always seemed strange to me... virtually no one I knew had the slightest interest in it. So I would not be too surprised if that also happens here.

For anyone interested in the content of the book there is a preview available under Google Books.

Mr Bill said:

But something that always seemed strange to me... virtually no one I knew had the slightest interest in it. So I would not be too surprised if that also happens here.

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Thanks!

I think it's because these topics are quite abstract. And there are no shortcuts, which means you have to deal with it more intensively. But you can at least acquire basic knowledge without going into the details.

Otherwise you'll always be sitting in front of an Enigma and that's not a good feeling in the long run

What would be a first step?


Electronics

How does electricity work in general? When does it flow and when does it not? This is easy to explain, even though you can't see electricity.


Mechanics

The art of power transmission. One wheel spins slowly and another spins quickly. At least you can observe something here. There are some principles and components you should know.


Optics

How do I direct my subject, i.e. light, to the film so that the image is sharp, has appropriate contrast and, if possible, has no errors? Convex and concave lenses, one lens corrects the errors of the other, all lenses in one objective are a closed system coordinated with each other.

You don't need anything more to get a basic understanding.

I'll be happy to elaborate on this later, making it understandable, short and hopefully entertaining

Optics is an area that I need to study. I have a reasonable understanding of electronics enough to allow me to understand what happens in the circuits. I've a solid understanding of the mechanical side. Optic theory is still black magic though. I've been reading some on the topic and am gaining more of an understanding of the design of a lens but my level of knowledge is about at the same level as is my dog's understanding of how to drive a car. He knows that I sit in a certain spot in the truck and turn the big round thing back and forth to get places but that's as far as his understanding of driving goes. That's where I am at with the science of optics.

88E30M50 said:

Optic theory is still black magic though. I've been reading some on the topic and am gaining more of an understanding of the design of a lens but my level of knowledge is about at the same level as is my dog's understanding of how to drive a car.

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Ha ha, smart dog!

I've been through the same sort of thing and have more than a handful of books on or related to optics. To me the most "useful" one, at least with respect to understanding image formation, was Warren J Smith's Modern Optical Engineering (2nd edition, around 1990); (I bought it new but see this edition on Amazon for about $12 now)

Optics can be seen in several ways, including "physical optics," probably the most complete way, or "geometrical optics" which is more directly useful in photography, imo. Geometrical optics tends to see light as traveling "rays" which can be "bent" (refracted) by a lens. But...there is a limit to how precisely these so-called rays can be directed, which sets a physical limit to how much detail a lens can "resolve." Limits aside, "geometrical optics" allows one to use "ray tracing" to design lenses and even establish those simple equations to relate "focal length" of a lens to where an image is formed. (As a note those simple equations apply only to a narrow zone around the optical axis of a lens; we sorta rely on a trust in quality of a lens to infer other things.)

More elementary books tend to just say, here is the refractive index of the glass, and and Snell's law can be used to calculate how much a "ray" is "bent" (refracted) at a surface. But it turns out that the refractive index varies with the "color" of the light (we've all seen those images how a prism spreads a beam of light into different colors, right?) In glass catalogs there is a so-called Abbe number (after Earnst Abbe?) that allows calculation of the specific index. Which can then be used for "ray-tracing" several different "colors" (wavelengths) of light through a lens. So the guts of a well-corrected lens are much more complicated than what meets the eye.

Anyway my rec is for Warren Smith's book, realizing that it takes a certain mindset to deal with it. That aside I am doubtful that it has any direct application to actual lens repair.

As a note, for anyone who likes the teaching style of Feynman's Lectures on Physics (these, from early 1960s, are now freely available on internet) Feynman did have one lecture on "the origin of the refractive index" (or similar wording) as well as a bit on Snell's law, etc.

Very good info. Both Smith's and Goldberg's books have been ordered. While I don't expect to see lens repair info in either, both should give me the basic info needed to understand what I am looking at when I find myself in front of a pile of disassembled glass and wondering how it all works.

Thank you to both of you for the excellent recommendations.

Smith's Modern Optical Engineering is a good book for an approach to the science of optical design and engineering. It's pretty technical but you can skip over many of the harder formulae/computations if you aren't aiming to become a optical designer. However, devoting effort to understanding some of the simpler math (like understanding the thin lens equation, dispersion, or learning what a pupil is) can be really helpful to understand how lenses focus images at different distances, how two lenses combine their focal lengths, why lenses are designed the way they are, why and how different glasses are combined to make an achromatic lens, etc. Nothing in Smith's book would directly tell you how to repair a camera lens; it's more about principles.

An older book that doesn't get mentioned much but is more camera-lens-oriented and less technical than Smith is Arthur Cox's "Photographic Optics."

For electronics, a classic text is Horowitz and Hill's "The Art of Electronics." Again, you don't need to master it all if you aren't designing circuits, but understanding how the components function and that they aren't magic is helpful.

I haven't ever read Norman Goldberg's book, although I did just look at the Google books preview, thanks. It is much more camera-specific and applied than the above. It occupies a middle ground - not a repair manual, nor an engineering textbook, but describes subsystems in enough detail that you can maybe understand what they're supposed to be doing. The optics part at the beginning did not shy away from math, which likely would put some readers off, but I appreciate.

We had one of Rudolf Kingslake's texts on our shelves at home when I was growing up.
I'm thinking it was probably "Lenses in Photography: The Practical Guide to Optics for Photographers" but I could be wrong.
My father had a story about it. One of our neighbours in the Toronto area was an engineer working on the Avro Arrow project. He came over to talk to my Dad. Apparently they were having problems with windscreen reflections causing problems for the pilots, and knowing that my Dad worked for Kodak, came over to ask him if he knew who they could talk to. Dad pulled the book off the shelf to show the neighbour, who took one look at it and exclaimed something like "Rudy! I should call him up!"
Apparently, they had gone to school together.
The world was somehow smaller in the late 1950s.

Another one:

MattKing said:

We had one of Rudolf Kingslake's texts on our shelves at home when I was growing up.
I'm thinking it was probably "Lenses in Photography: The Practical Guide to Optics for Photographers" but I could be wrong.

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Thanks for the mention!

I got a lot from this book by Kingslake, I also find it excitingly written:

For me this series is one of the most comprehensive representations of photography, written in an understandable and vivid way.

Optics are described in the edition „The Camera“.

These excellent books are used, at least here in German-speaking Europe, almost given away.

A treasure chest especially for analog photographers.

Andreas Thaler said:

Another one:

Learn Camera Repair: Vivitar - Fundamental Optics For Repair Technicians

https://learncamerarepair.com/product.php?product=1651&category=0&secondary=0 This is a great intro to optical design and repair, originally published by Vivitar. Useful for any kind of lenses, not just Vivitar's products. ibid. 39 pages: Lenses Apertures and Stops Aberrations Camera...

www.photrio.com

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This is the book I've been going through so far.

Interesting specialist articles on camera technology can also be found in the editions of The Camera Craftsman, which begin in the 1950s.

The independent camera repairers were kept up to date and so were able to improve their skills. Especially when electronics swept over the previously purely mechanical camera landscape like a tidal wave.

You can therefore use these articles for self-study: