Constant quality from memory Cards

Rocket

Rocket

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Tony
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I have been meaning to ask this question for some time.
Wondering if there is a time period when memory cards loose quality, I am still using a 4 year old CF card and seems to retain quality, but do wonder if there is a time when they start to deteriorate..
 
Graham W said:
they only record 1's and 0's so they either work or they don't!
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+1

This is about the same thing than a light bulb… works or not.

Basically, the number of records and erases is limited but you
won't have a chance to experience it in a life time.

When I shoot a job, I always save to the two cards, one backing
up the other.

If I shoot wildlife, where I need the maximum in memory, I'll setup
to fill one card and then the other.
 
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It has no bearing whatsoever on quality. It's digital.

It's not like a VHS tape :)

It just stores data.
 
Just to add to the above, flash memory does have an expected number of read write cycles before failure. It's a lot, but they don't last for ever.

But as for quality loss, if you consider each bit of data held as a switch that is either on or off, all your image does is operate a whole bunch of switches, the software then reads back which switches are on and off to create an image.
 
Phil V said:
the software then reads back which switches are on and off to create an image.
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Yes, in the case of jpg, tiff, etc… but not RAW as is is no image.
 
Kodiak Qc said:
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Yes, in the case of jpg, tiff, etc… but not RAW as is is no image.
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I was trying to keep it simple, from a digital point of view they're just on or off (1's and 0's) whether it's a JPEG, RAW file, an excel spreadsheet for your monthly accounts or instructions to build a bomb :D.
 
@Phil V
I know very well what you were doing and my note was
certainly not thought for you but for other readers!

Sorry for not making this clear!
 
Of course a memory card can degrade to the point where *some* of the data within a file is stored and/or read erroneously, so you may get the files off the card but some of the data in them could be corrupted.

This is where error checking will come into it as I'd presume all file formats, be they jpeg, RAW or whatever, will have some form of checksum built into them so a corrupted file can be detected.
 
Vertigo1 said:
Of course a memory card can degrade to the point where *some* of the data within a file is stored and/or read erroneously, so you may get the files off the card but some of the data in them could be corrupted.

This is where error checking will come into it as I'd presume all file formats, be they jpeg, RAW or whatever, will have some form of checksum built into them so a corrupted file can be detected.
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From the OP, I took his question to mean image quality rather than data corruption?
 
odd jim said:
From the OP, I took his question to mean image quality rather than data corruption?
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Oh yeah, I was just speculating that odd individual errors on a memory card could potentially produce individual pixel errors in the image, degrading the overall "quality" of it, but that the files must have some kind of checksum or hash built-in to detect this and flag the file as invalid.
 
In a nutshell, Once a card starts giving you errors it's time to throw it & use another one.
 
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