The 64 GB card buys one more GB / $$, but that's not helpful if half the card is never used.
Correction / clarification to OP:
“or, will it begin to use previously unused (previously unrecognized) sectors, maintaining useable memory close to 32 GB?”
32gb are SDHC and above that is SDXC.
How old is your dashcam?
Older devices might not support SDXC but newer ones usually do even when they only say 32GB or 64GB, etc.
Unfortunately, without testing it or finding someone else who has tested it you can’t really be sure.
If I use a 64 GB micro-SD card in a dashcam only rated for a 32 GB card, I know the dashcam will only recognize ~32 GB (slightly less, actually) of this card. But, as sectors go bad, will the cam recognize only the ~32 GB minus the lost sectors, or, will it begin to use previously unused / recognized sectors, maintaining useable memory close to 32 GB?
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Sounds like the 32 GB is an addressability limit of the dash cam, so, as you noted, you can put in a bigger card, but the cam wont use then extra space.
As to readability, all SSD storage already has extra cells in the device and it manages bad sectors and worn out sectors automatically. So if you by a 32 GB drive, it actually has more storage already onboard as “spares” as sectors go bad. So getting a bigger drive really doesn’t buy anything in this case. The more critical factor, is probably the reliability and speed of the particular SD card.
Get TWO (2) fast 32GB chips - if one gets full you have a backup with no data corruption issues for ~ $15 with SanDisk 10 year wtty. 51% discount if you hurry. ;-)
SanDisk Ultra 32GB UHS-I/Class 10 Micro SDHC Memory Card With Adapter - SDSDQUAN-032G-G4A
AMZN link:
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I use 64 and 128 GB in my dash cams. They simply seem to go bad after a while. I sure haven’t had an issue with lost sectors, that probably is not gonna be an issue as the small amount of space is meaningless with that much overall space.
later
We Need To Talk About Dashcam Video Quality
https://www.youtube.com/watch?v=SowUTOrhzOg
Almost EVERYONE is Wasting Money on Dash Cams
https://www.youtube.com/watch?v=4AnyhHl3_tE
Here’s Our Response To That Video From Linus | BlackboxMyCar
https://www.youtube.com/watch?v=w3nVVdh-wic
These look to be the best of the bunch tested as they all have nearly the same processors and processing chips with minor changes.
Thinkware U1000 4k30
Blackvue DR900X Plus 4k30
Viofo A119 V3 1440P 60fps
My old dash cam simply refused to use a 64 GB card.
Generally speaking, no.
The cameras cant dynamically just shift over to good sectors outside the 32 GB of formatted memory they are able to recognize.
In fact, it may not recognize the larger memory card at all. I had someone this week who bought an old digital cam, for example, that can only recognize a card 2 gb or smaller. They tried a 4 gb card and the camera couldnt detect it.
So generally no, exceeding the memory card limits does not work, the limits are there for valid technical reasons.
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