observation on camera reliability

[flavio81]

A gear or special cam can be made by someone with a hunk of brass and a file..

For a camera? A gear? That will work just fine? No, you can't.

 

[flavio81]

I personally would prefer an electromagnetic leaf shutter like in the Hasselblad HC lenses over a fully mechanical one any time. As much as i like mechanical engineering and clock/watchmaking, but dependability-wise i think the less small moving parts the better.

Me too. That's why i happily switched from RB67 system to the Bronica ETR system. Love those electronic shutters, they work just fine.

 

[Don_ih]

For a camera? A gear? That will work just fine? No, you can't.

You aren't familiar with watchmakers, then. You need some more specialized tools to do it - more than just a file, that is - but all these things used to be made by skilled people. There are still people who can do it.

 

[Photomultiplier]

Yes, you can make spur gears the proper way with basically an milling machine, an dividing head and an set of gear cutters. As long as they use standardized tooth profiles (involute is standard in mechanical engineering and cycloid is used in watchmaking)
I did that myself. Gets boring after the N-th wheel because i had to do everything manually and repeat the process for each of the xx teeth Filing won't give you the proper shape. The guy from ancient greece who did the antikythera mechanism admittedly used a file,
but his tooth profile was just triangular and the gears for sure didn't mesh very smoothly

But it gets difficult if we are talking about complicated metal parts and shapes. Without specification it will be very time consuming, especially if it has to be fitted by trial and error and the whole thing has to be disassembled and reassembled every time.

A good way to start would be to measure the part carefully on an coordinate measurement machine or profile projector. Otherwise it appears very difficult to get the dimensions right. At least if the whole thing should be a real way of manufacturing spare parts.
Normally, for such reverse engineering things, one would measure several parts and therefore get the nominal dimensions and tolerances.

Many of those high precision mass produced parts in shutters and other mechanisms were made with specialized tools (dies etc). Those tools often have been made on extremely precise and accurate jig borers and jig mills. I am pretty sure that everytime one sees
a set of precisely positioned holes in some part, the jig was made on such a specialized machine.
Today the precision can often be attained with more regular CNC machinery, but the problem of establishing the design spec (dimensions and tolerances) stays the same.

I personally started small and made some replacement screws for the ones that were mangled. This was useful and screws, even small ones, can be made without special tooling and the original dimensions can also be easily determined.

 

[Sirius Glass]

I am in the fortune position to own dozens of cameras. Many are mechanical ,some are electronic, some only a few years old, Some are many decades old(my oldest will be 100 next year), some frequently used, others I've been sitting on the shelf for years.
I made a few interesting observations I like to share. Keep in mind that YMMV.
1. Electronic cameras are not less reliable than mechanical cameras. This is especially true for shelf queens.
2. Reliability as little to do with a country of manufacture.
3. es, mechanical cameras can be serviced for a long time but it seems they also need to be serviced more frequently.
What is your experience?

I agree somewhat with 1 and 2, but not on 3. I have found that all mechanical cameras tend to work longer than electronic cameras as long as the are used and maintained properly. However the bigger issue for reliability is how well the camera was designed and built.

 

[flavio81]

You aren't familiar with watchmakers, then. You need some more specialized tools to do it - more than just a file, that is - but all these things used to be made by skilled people. There are still people who can do it.

You wrote:

A gear or special cam can be made by someone with a hunk of brass and a file.

I indicated you need a lathe and other tools... And I also remarked that even then it's possible that the piece will not have the required hardness (i.e. for advance gears) or precision (i.e. for 2nd curtain cam). Watches don't require high strength, only correct dimensions.

Go inside a real pro mechanical camera like a F-1 or Nikon F2/F3 and you will find mirror-polished gears of special alloys. Not something that a watchmaker would have in stock easily.

 

[flavio81]

YBut it gets difficult if we are talking about complicated metal parts and shapes. (...)
Many of those high precision mass produced parts in shutters and other mechanisms were made with specialized tools (dies etc). Those tools often have been made on extremely precise and accurate jig borers and jig mills. I am pretty sure that everytime one sees
a set of precisely positioned holes in some part, the jig was made on such a specialized machine.
Today the precision can often be attained with more regular CNC machinery, but the problem of establishing the design spec (dimensions and tolerances) stays the same..

Sounds more difficult than programming a microcontroller with a built-in A/D converter to measure light from a sensor and actuate an electromagnet with the correct timing. Which is what would be needed to replace an hypotetical completely-dead electronic auto-exposure camera circuit made of unobtainable parts in year 2022. In year 2030 it will be even easier.

In fact...

A guy already made a completely new replacement circuit for the Bronica EC-TL electronic boards. It was easy to design, easy to make, and it works.

Yet people think electronics are some sort of arcane objects whose replacements can't be made, only sourced from a distant galaxy (or a donor body). The same people think about mechanics:" oh yeah everything that spins can easily be made by the watchmaker next door for pennies..."

Right?

 

[Photomultiplier]

Yes, that was the thought behind my example with the 203FE. This technology level is more or less easily handled by any competent electrical engineer. When you start on monday, you probably will be able to photograph by the weekend with the hand wired breadboard lab-prototype crammed inside
the camera. The task that this circuit board has to do is just not that complex.

Is there information about the Bronica replacement board on the internet?

The Bronica you mentioned is a good example of this kind of mechanical nightmare where layers upon layers of interconnected springs and levers form a maze that is often hard to comprehend. I just googled and there were pictures of the mechanism.
Imagine hand-fitting a replacement lever without manufacturer specifications available in such a contraption. Almost unthinkable.


When simple mechanics are coupled with well made (and in an ideal world also documented!) electronics, then one would have the best of both worlds. It would be robust because the insane complexity of performing the operating sequence(s) is transferred into an firmware that can be easily modified during
development and be utterly reliable when properly programmed and tested. So it would be not that difficult to grasp the functioning principle (and therefore easier to maintain) AND on the other hand it would have far less places where something mechanical can go wrong either by wear, dirt or hardening lubricants etc.

A Hasselblad magazine for example consists of multiple spur gears springs, levers, a special coupling built into the gear with the missing tooth visible from the outside, cams and so on. Works well if serviced but if it gets old, the deteriorating lubricants can cause a lot of misbehavior like overlapping frames, irregular spacing,
not stopping at frame 1 (a small locking lever that gets stuck when the grease gets hard). I do not really worry about that issue as the magazines can be pretty easily cleaned and brought back in working order.
With the above mentioned approach, it would merely be a motor with a reduction gear to move the take up spool, an encoder to sense the angle of the shaft, a small 8-bit controller, a bit of discrete stuff (transistors etc) and some contacts to the body. The body would tell the magazine to advance by one frame and the controller
would know for each frame how much it has to turn the spool. And that would be it. No grease, no springs, no levers, no couplings.

I like both, fully mechanical devices and electronic ones (as long as the electronics are of very high quality). Both have its charms. But sometimes i would rather have more of its functionality implemented as wear resistant electronics.

But as i have repaired a lot of equipment in my life, i somehow always have a kind of low-key anxiety that the thing i use will break. Every time i press the release button on my Hasselblad i have this thought The curse of the repairman.
Not to mention that the main spring in my old silver 80 Planar broke when i was on the mountain and i missed the sunset because of that.... This was the only real fault i ever experienced. There was a silver 150 Sonnar where a leaf shutter blade cracked, but this lens was so beaten up, i don't think it can be blamed.

 

[Photomultiplier]

I think i found it: https://www.photo.net/discuss/threads/bronica-ec-shutter-problem.505989/

 

[wiltw]

I like both, fully mechanical devices and electronic ones (as long as the electronics are of very high quality). Both have its charms. But sometimes i would rather have more of its functionality implemented as wear resistant electronics.

But as i have repaired a lot of equipment in my life, i somehow always have a kind of low-key anxiety that the thing i use will break. Every time i press the release button on my Hasselblad i have this thought The curse of the repairman.

More often it is 'electrics' that fail, and not 'electronics', although sometime differentiation is subtle

1. Nikon wiper resistor not reflecting the rotary position in the appropriate resistance change...electric or electronic?
2. Minolta Autometer IVf electrical contact switch reflecting closed vs. open, to detect incident dome vs. reflective light measurement
3. BTW I had my Canon 5D main circult suddenly fail in the middle of a shoot...electronic or electric?!
4. My 45 year old CdS meter in Topcon camera suddenly stopped metering light, just sitting in a case in storage!

I also had one Bronica ETRS shutter issue, caused by a mechanical issue of the too-long interlock pin on a film back (purchased used) causing the reflex mirror to not flip up fully, so that the mechanical shutter actuation lever would not move (and so the electronic timer never closed the electromagnetic shutter because it had never opened!)

 

[Photomultiplier]

Good point.

My Spotmatic F also has developed some issues with the aperture variable resistor, but a bit of movement cures it. Contact problems are extremely common. Even connectors with gold plating sometimes become unreliable with age. Never trust connectors, regardless of how well they were made.
I once repaired a really heavy test instrument (spectrum analyzer) that got decomissioned because it did not work anymore. The solution was to just clean some internal edge connectors and it was good to go again.

point 1 & 2: electrical (where mechanics and electronics meet)
point 3: dont know, probably electronic
point 4: difficult to tell

Electromechanical parts are an achilles' heel of electronics.

 

[Bill Burk]

Having had Olympus OM-4 fail on me 'every single time', I am not pleased with electronic cameras. It's ALWAYS the batteries, and it ALWAYS comes to life if I have spare batteries. Then it will last much of a week. Sometimes I sweat a weekend knowing I don't have any more spare batteries.

But I ALWAYS miss a shot.

Pentax ES-II has been rock steady reliable. Funny though... when I have the baseplate off to perform a field repair, there are times when simply the way I attached the electrical connector to the circuit board fails on first few tries then suddenly springs to life with a certain wiggle. Quickly putting that back together it will perform flawlessly for years.

So I have grown attracted to the OM-3 (which ALWAYS has battery problems) because it will work anyway I no longer miss shots.

And I like the Spotmatic F (which has a funky ability to look like it's on the right f/stop and shutter speed until you realize it's too dark).

 

[Sirius Glass]

What is the most reliable circuit? Open circuit
What is the least reliable circuit? Short circuit

 

[Don_ih]

I indicated you need a lathe and other tools... And I also remarked that even then it's possible that the piece will not have the required hardness (i.e. for advance gears) or precision (i.e. for 2nd curtain cam).

The point is, replacement parts can be made. Or was it actually impossible to originally make the parts found in an 80-year-old camera? Were the prototypes of those all made using stock parts - leftover bits from sewing machines? I guess they could have just used their CNC....

 

[Photomultiplier]

That is right. Everything that has been made in the first place, obviously can be made again.
But from the practical point of view, it depends heavily on the effort and cost. Even for making the 80 year old shutter, they had a lot of custom made tools. Of course, prototyping sometimes involves different approaches but don't forget: They at least had the technical drawings for the
parts they made, even if they filed them from stock material.
And they had company budget, so they could employ tool and die-makers and even make the tooling during prototyping, because those designers knew what they did and they for sure did not need to try out each and every part beforehand. Sometimes, parts and assemblies turn out just right
in the first try. I cannot imagine that e.g. Compur worried that much about some tools that had to be scrapped because a modified revision of the part was needed. The production volumes were high, labor costs were low and so they were able to bring those complicated mechanisms to market.

I bet that if i would get quotes for the initial costs of tooling, prototyping etc for something like a Copal 1 shutter, the project would be dead before it started.
Complex products can only be developed if there is a large enough market for them. Or they can be continued to be produced because the machines and tooling are long paid for.
But starting again in a totally different economic environment with a product that basically comes from a bygone technological era is very difficult. At least when not done by a company with a large enough budget.

Thats why i think that the hybrid approach is one that is suitable for todays demands. Reduce the labor intensive mechanics as much as possible and implement the rest of the functionality in electronics that can be produced to high quality without any hassle.
Circuit boards can even be soldered by hand if there are no component packages like ball grid arrays. So if one wants to try making some custom replacement electronics, it can be done with almost zero initial cost. Just parts + bare PCB board.
It would not surprise me if the the sequencing mechanism in an typical medium format body, which took the Hasselblad engineers months or even years of brain racking to develop, can be programmed within a few days when using the electromechanical approach.

I absolutely love pure mechanics, they can be of an aesthetic quality that cannot be matched by any electronics, but they can be an absolute nightmare to develop and manufacture in our time.

Regarding aesthetic mechanics:

 

[BrianShaw]

LOL… Any time a discussion includes the words “theoretically “ or “conceptually” I tend to tune out.

 

[Light Capture]

Maybe one should discern between reliability and longevity.

During the projected life span of a camera (lets say 10years) i think the electronic ones will be the winner. There is often not that much intricate mechanical stuff that can go wrong. Of course, there are motors, gears, levers etc but the sequence and timing is largely
controlled by microcontroller and not by small moving parts that slow down when lubricant gets old/cold like in an leaf shutter. Also they sometimes use better materials because they are newer. I would bet that the latest leaf shutter blades are far more durable than the ones from the
60s.

But when long term maintenance/preservation comes into play, the mechanical ones could be easier to handle.
A lot of electronic faults can be repaired easily, even if the exact same spare part is not available, one can use functional equivalents. (Diodes, Transistors, plain contact problems, cracked solder joints etc). But it takes specialists to find those faults, the layman usually
wreaks more havoc during repair attempts in electronics than the fault itself

The real showstopper are custom programmed or custom made ICs which are unobtainium
and it would require a sometimes prohibitively huge amount of reverse engineering to duplicate the functionality.

I would feel confident for example to design a replacement PCB board for a Hasselblad 203FE which largely emulates the original behavior. There is not that much stuff involved. Basically light metering, a bit of display controlling (that would most reverse engineering),
some buttons and communication with the lenses (also reverse engineering with a functioning body/lens) and state machine programming. The shutter itself is just 2 small solenoids for curtain 1 and 2 as far as i can tell.
BUT: Nikon F6 replacement electronics? I would never even try that. Far too much peripherals (AF/exposure) to talk with, when some of those are damaged it cannot even be attempted.

There is some technology level up to which one can fully understand all the interrelations between the components.

Mechanical "unreliabilty" very often stems from neglect, lack of service, old lubricants, dirt etc. When a camera is 50 years old, it seems that it has to be stripped down far more to clean out each and everything than normally done by service technicians.
Nice example: Everyone knows about the mirror dampening foam strip against which the mirror slaps. But e.g. in Hasselblads (at least without the GMS) there are 3 foam cushions beneath the mirror. If they deteriorate after some decades, the mirror wont be held properly in place anymore and
random focusing issues arise. So after a long camera life, it starts to be more of an restoration than just service/repair.
Dirt and old grease is a good lapping compound, often to be seen in old pendulum clocks that never got serviced. Some day, they stop. People increase the weight and they run again. Then they stop completely and they go to the clockmaker and say: The clock stopped working, but there
cannot be that much wrong, it worked flawlessly for 60 years! End of the story: Pivots are worn out, bearings are worn out and often worked out to some oblong shape, gear teeth are worn... Totally trashed and it needs a lot of work to get it back to life.
If the clock would have been at the clockmakers for servicing every 5-10 years, the wear would be far less and it could continue its service life for a long time.
Same with cameras.

The good thing with purely mechanical cameras is that they usually consist of only metal and that should be very stable in the long term but they have to be properly CLAd more regularly.
What i hate most about modern cameras is that stupid rubber material that gets sticky and deteriorates. I'd rather have plain metal, even if its not that comfortable.

Regarding 3D Print: Proper machine tools are alien to many people and then 3D printing is brought into the field as solution because its a new trendy technique that is accessible to a broad audience. But they overlook the fact that many camera parts have extremely tight
tolerances and surface roughness to meet and i doubt that it could be achieved by 3D printing even in the mid-term and with professional machines. If someone has more information about what is possible regarding finish and tolerances today, i would appreciate it.

A lot of stuff could be printed even now, for sure. (Cranks, knobs, battery doors, maybe even sprocket wheels) but i just dont see it for those precision machined parts that have to be made to watchmakers tolerances or that need bearing surfaces (need to be reamed).
Also the material has to be suitable for printing.

What also worries me are springs, but even for those there would be solutions to make them. But it needs specialist knowledge and equipment at a company specializing on springs.

@RalphLambrecht: Regarding point 2: I have a Pentax Spotmatic F that sat in the cupboard for nearly 20 years without being used. After that i got it in 2007 and used it for several years. Up to this day, there are no hiccups, the times are spot on, the diaphragm moves quick.
So the japanese seem to know how to lubricate (or rather NOT lubricate, as i suspect that they are using material pairings that dont need it) a camera while european cameras cause far more trouble. One would think that european cameras should be also that reliable, but
if a Hasselblad sits unused for that long, it needs a full overhaul for sure.

3d printing can create almost any part as long as materials can satisfy the purpose and with process considerations.
Anyone can slice a file and send it to a 3d printer but knowing how to design something to function properly and avoid things that will not function or wear properly is a key.
There are several different 3d printing processes and multitude of materials that can satisfy almost any use. With that said many of them are not feasible either financially or due to complexity.

ABS is the cheapest engineering material for these printers but it's very hard to print. Industrial printers or heavy modifications to the printer are required. Carbon filled materials and high end / high temperature plastics require even more considerations.
ABS+ and other ABS mixtures with additives print easier but still not easy. Properties are not as good as ABS although not far off.
PETG is also in family of engineering plastics but G means additives so it can be printed effectively. It is very strong but brittle. It requires lots of considerations as it doesn't function as PET the plastic bottles are made from. PET bottles are very flexible. PETG of the same thickness breaks easily. Almost like glass.

All ABS and PETG filaments I dealt with are opaque and don't let light through.

0.1-0.2mm precision is usually achievable with careful planning and design.
This can be taken much higher if parts are post processed / machined either during or after printing. There are printers that will machine printers after each layer. Not cheap and adds programming and design for machining since parts are printed larger and then machined.

SLA printers can print to much higher precision and there are some that can be extremely precise. They are however complex to use since prints have to be washed and cured.

The process needs to suit final use. So, when I need a broken gear for something it's machined. Unless it's bigger and teeth are 3d printable...and material is suitable.
Quite often gears can be flat machined on CNC. It can't produce sharp corners on tooth base but if it's designed properly it won't interfere. Structural strength stays almost the same. It's definitely useable process for these purposes.

Hasselblads as well as most other cameras are made with failure points where it will break a gear or tooth in order to protect the rest of it. Even though there were lots of parts to be found most used consumable parts like these aren't available. They're what's used the most.

 

[Sirius Glass]

The point is, replacement parts can be made. Or was it actually impossible to originally make the parts found in an 80-year-old camera? Were the prototypes of those all made using stock parts - leftover bits from sewing machines? I guess they could have just used their CNC....

Time to get real again. The only parts that will be remade from scratch now will be cloth shutters for Graflexes and Speed Graphics. No machine shop will make parts because the cost is too high. When parts are no longer available from the factory, repair facilities and private stashes is from other cameras. Yes it is theoretically possible but not practical.

 

[Light Capture]

That is right. Everything that has been made in the first place, obviously can be made again.
But from the practical point of view, it depends heavily on the effort and cost. Even for making the 80 year old shutter, they had a lot of custom made tools. Of course, prototyping sometimes involves different approaches but don't forget: They at least had the technical drawings for the
parts they made, even if they filed them from stock material.
And they had company budget, so they could employ tool and die-makers and even make the tooling during prototyping, because those designers knew what they did and they for sure did not need to try out each and every part beforehand. Sometimes, parts and assemblies turn out just right
in the first try. I cannot imagine that e.g. Compur worried that much about some tools that had to be scrapped because a modified revision of the part was needed. The production volumes were high, labor costs were low and so they were able to bring those complicated mechanisms to market.

I bet that if i would get quotes for the initial costs of tooling, prototyping etc for something like a Copal 1 shutter, the project would be dead before it started.
Complex products can only be developed if there is a large enough market for them. Or they can be continued to be produced because the machines and tooling are long paid for.
But starting again in a totally different economic environment with a product that basically comes from a bygone technological era is very difficult. At least when not done by a company with a large enough budget.

Thats why i think that the hybrid approach is one that is suitable for todays demands. Reduce the labor intensive mechanics as much as possible and implement the rest of the functionality in electronics that can be produced to high quality without any hassle.
Circuit boards can even be soldered by hand if there are no component packages like ball grid arrays. So if one wants to try making some custom replacement electronics, it can be done with almost zero initial cost. Just parts + bare PCB board.
It would not surprise me if the the sequencing mechanism in an typical medium format body, which took the Hasselblad engineers months or even years of brain racking to develop, can be programmed within a few days when using the electromechanical approach.

I absolutely love pure mechanics, they can be of an aesthetic quality that cannot be matched by any electronics, but they can be an absolute nightmare to develop and manufacture in our time.

Regarding aesthetic mechanics:

Agreed. Something like Copal and Compur shutter wouldn't be feasible at all today.
Some of those small gears and components were pressure cast and some were stamped. Number of required tools and machines required to drive them with adequate precision would be mind boggling.
Additionally some were machined on very precise copy machines. Could be made in some alternative way but certainly not straightforward.

Electromechanical approach is certainly the best possible way to do it today.

 

[Light Capture]

More on topic. While electronic bodies are reliable I have 5 Nikon EL and FE bodies and 3 are not working. 1 of them wasn't working when I got it but they can't be really repaired easily. Parts required most of the time can't be fabricated or found anymore.
Have few of 2000 series bodies and it's common that older ones have malfunctioning electronics. Newer ones were more reliable but it could be just age.
Some of Nikon F80's have battery drain or broken back door latch.
Have bunch of broken Canon EF bodies.

On the other hand all mechanical Nikons, Leicas, Hasselblads were repairable.

 

[Sirius Glass]

More on topic. While electronic bodies are reliable I have 5 Nikon EL and FE bodies and 3 are not working. 1 of them wasn't working when I got it but they can't be really repaired easily. Parts required most of the time can't be fabricated or found anymore.
Have few of 2000 series bodies and it's common that older ones have malfunctioning electronics. Newer ones were more reliable but it could be just age.
Some of Nikon F80's have battery drain or broken back door latch.
Have bunch of broken Canon EF bodies.

On the other hand all mechanical Nikons, Leicas, Hasselblads were repairable.

That is why I have Hasselblad V Series and not the 200 or 2000 series.

 

[Photomultiplier]

Hasselblads are very repairable according to my experience. They have been manufactured until 2013 and spares are often available.
My local service technician officially got the whole spare part stock and all the jigs from the austrian Hasselblad distributor in Vienna.
He even had all the needed parts for my CF lenses Prontor shutter. (Escapement, leaf actuating ring etc)

He said that he has done certain tasks on the 200 series but they are a completely different beast than the 500 and they are probably best cared for in Sweden.
I see it as a privilege to have a skilled technician in my city.
And he is relatively young, compared to many others who are retiring.

 

[Sirius Glass]

Hasselblads are very repairable according to my experience. They have been manufactured until 2013 and spares are often available.
My local service technician officially got the whole spare part stock and all the jigs from the austrian Hasselblad distributor in Vienna.
He even had all the needed parts for my CF lenses Prontor shutter. (Escapement, leaf actuating ring etc)

He said that he has done certain tasks on the 200 series but they are a completely different beast than the 500 and they are probably best cared for in Sweden.
I see it as a privilege to have a skilled technician in my city.
And he is relatively young, compared to many others who are retiring.

My Hasselblad repairman advises against my buying the 200 and 2000 series, and that if I buy a 1000 or 1600 version it only be used to occupy a shelf for display.

 

[Light Capture]

That is why I have Hasselblad V Series and not the 200 or 2000 series.

I have both but like 200 and 2000 series better. There isn't much point in having them unless you have F or FE lenses for them.
Those that I got working are still working fine. 2000 series with W suffix and 200 series have newer electronics and are less likely to fail.

 

[Sirius Glass]

I have both but like 200 and 2000 series better. There isn't much point in having them unless you have F or FE lenses for them.
Those that I got working are still working fine. 2000 series with W suffix and 200 series have newer electronics and are less likely to fail.

Since I already have the 30mm Fisheye C, 903 SWC [38mm CF], 50mm CF, 80mm CF, 150mm CF, 250mm CF and 500mm C, I do not see myself rushing to buying a F or FE lens.