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Shelf life of assembled electronics
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Siwastaja:
I call bullshit about Berni's comments about the flash.

If the camera designers are not total morons (which they could be, though, in which case I will stand corrected), for the firmware, they use the kind of flash which
1) is NOT unreliable, and does NOT hide the unreliability by ECC. Might not have ECC at all.
2) has data retention of at least 50 years or so guaranteed by manufacturer, and this is at elevated temperature.

This is usually internal to the microcontroller(s), sometimes external, with size in hundreds of kilobytes to maybe a few megabytes.

This is totally different to USB flash drives or SD cards which use flash technology with far higher storage density, the focus being least $ per GB, with (sometimes) questionable retention time, unless you are careful what you buy and who you believe.

But, by default, I would give the microprocessor manufacturers benefit of doubt and assume their guarantees hold. What else can you do, after all. Same for other parts with shelf-lifes.
AndyC_772:

--- Quote from: pcm81 on November 30, 2022, 11:05:57 pm ---Photography is a hobby of mine and often when discussing high end nikon cameras and lenses the comments get made like "it will outlast you". Which is true at-least about lenses,

--- End quote ---

I've just been through, let's call it, a relevant experience. I decided to get back into photography after a few years' hiatus.

I was planning a holiday which would involve wildlife photography, so I figured it would be a good idea to test my equipment and re-familiarise myself with how it all worked.

It didn't start well. My Canon 100-400 L IS threw intermittent error codes whenever I turned IS on. The repair centre diagnosed a faulty IS unit, but said the lens was no longer supported by Canon. No spare parts available. I sold it as-is and bought the mk II version to replace it, which turned out to be a much better lens anyway, but it was an expense I could have done without.

A few weeks later I went out with my 24-70 f/2.8 L, and came back to find some shots significantly mis-focused at f/2.8. Turns out this is quite common and is due to mechanical wear causing slop in the mechanism, and should be easily sorted with a routine service. But you've guessed it, no longer supported and no parts available. Once again, I sold it as-is and replaced it with the mk II, which is slightly smaller and lighter but otherwise barely any different as far as I can tell.

Feeling neglected, my 50mm f/1.4 prime decided to take a flying leap out of the cupboard where I store my kit. It has a focus mechanism that's oddly fragile, but fortunately spares are readily available and inexpensive, and there's a really good video on YouTube showing how to fix the exact focus issue that it developed as a result of its drop to the floor.

In the meantime I sent in my 5D mk III for service, whilst service is at least still available for that model. I still remember buying it new, and there's barely a mark on it... can't quite believe how old it actually is already. A dodgy rotary encoder needed replacing, which was surprisingly inexpensive, but it was still over £200 all-in to get it shipped, cleaned and calibrated. Still, I have a camera that should last well now, which is just as well as it can't be too long before spares for that model also dry up.

I also cleaned the focus screen of my 1DX mk II, and thought I'd scratched it in the process. (Note: this is *very* easily done - though the 'scratch' in this case actually turned out to be a fibre from a cotton bud, which was a relief). Nevertheless I was dismayed to find that the standard focus screen for this camera is - you've guessed - already discontinued, and the only place I could find a replacement was an Ebay seller in China. IMHO it beggars belief that such an easily damaged, critical part of a 1D-series camera should already be unavailable as a spare.

Finally, at least for now, another unfortunate accident befell my 70-200 f/4L. This was by some margin the oldest of all my lenses, and surprisingly, it's still under service support. Except in this case, that's irrelevant, as the cost to repair the apparently minor damage to the focus mechanism exactly equals the cost to buy a good used replacement. Odd, that.

My advice? Don't expect kit to last forever, because even if you don't use it much, even a minor problem could easily write it off if spares are no longer available. I've spent a small fortune over the last few months, on kit which should have been easily fixed, but couldn't be due to the lack of spare parts.

Instead, go out there, use your camera, and get the best value out of it that you possibly can.
Berni:

--- Quote from: Siwastaja on December 01, 2022, 12:09:33 pm ---I call bullshit about Berni's comments about the flash.

If the camera designers are not total morons (which they could be, though, in which case I will stand corrected), for the firmware, they use the kind of flash which
1) is NOT unreliable, and does NOT hide the unreliability by ECC. Might not have ECC at all.
2) has data retention of at least 50 years or so guaranteed by manufacturer, and this is at elevated temperature.

This is usually internal to the microcontroller(s), sometimes external, with size in hundreds of kilobytes to maybe a few megabytes.

--- End quote ---

Often bigger SOC chips are being used and those boot from external flash that often ends up being some form of NAND flash.

For example Keysight had issues with there most popular X3000 series scopes where early stage boot code would bitrot away rendering the scope completely bricked (official fix is sending it back to be serviced for free). So if it can happen to one of the worlds largest test equipment manufacturers, then id argue it could happen to one of the many digital camera manufacturers too.
tom66:
It very much depends on whether the firmware engineers have done their homework and know what they're doing.  And the hardware engineers must also appreciate the limitations of the hardware itself.

I was involved in an engineering project for a set top box that trick-played to the internal eMMC.  For those unaware, trick play is the function of being able to play and pause live TV, skip ads and so on.  In order to support that, you need to record the active stream of video to a memory device.  This is usually the demultiplexed compressed stream.

I think most people on this forum can see the issue already.  If you assume an MPEG-4 bitstream of about 10Mbit/s (1080i30 Freeview DVB-T2), 16GB memory device, after 1 year of usage 8hrs/day you are at 13TB written.  That is already 800 cycles across the NAND.  The Toshiba eMMC devices we were using were based on QLC NAND, a new technology at the time, and had a life time of about 1500 cycles.  However that lifetime was given at Tj=25C.  At Tj=50C, the lifetime was only 750 cycles.  The NAND got quite hot under continuous write and read operations, so 50C was a lot closer to reality.

To make matters worse the memory device was located about 5cm away from the main SoC, and when it died, it would bring the whole system down as the kernel debugger was left switched on printing kernel debug messages on an inaccessible UART about how the eMMC was not able to read or write blocks because of a device error.  The result is the box would take 10 mins to turn on and change channel 30 seconds after the remote control button was pressed.

And this could happen 18 months after you bought the device with relatively average usage.  I believe in the end a firmware update was shipped that turned off the debugger and we sent free USB HDD's out to customers who asked for them because trick play was now dead on their less than 2 year old box.

For what it's worth as an intern I tried to highlight this as a design flaw, but I was ignored.  The company pulled out of the UK market a few years later and focused on LatAm and so on.
PlainName:
LCDs can go off in various ways. Some stuff I am looking at currently has been in storage for between one and two decades. The displays suffer from blooming, missing columns, permanently dark splodges and being completely unresponsive (I guess that could be all columns missing).
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