JPEG - How long does it last?

[arunap]

Can anyone tell me how long a JPEG photo lasts without loosing quality?

[kenw]

forever. It is a digital data file. It, like any other digital file has no degradation over time.

The media it is stored on however, may have some degradation over time, CDs/DVDs may last only 10 years. Most expect them to last much longer if stored away from heat.

What you may be thinking of is compression loss, which is not a factor of time but of how many re-saves (not xfers, copies, etc) you do. Each SAVE of a JPEG file compresses the file a tad bit, resulting in some data loss. However, there are ways to minimize this such as setting the compression to the lowest possible value. For that reason, you should always keep the original JPEG file and always do SAVE AS creating a new file each time. Opening and closing without saving the original file does not degrade the file at all.

[Lghtning4u]

I was just wondering that myself. I have some stored on the yahoo and they definitely look faded and have some loss of detail. They have been there for 4 years and shot with film.

[arunap]

Ken, my thoughts again... Yes i am taking about data loss due to compression or copying..i usually store my original JPEG in my computer harddisk and also take a backup on DVDs. Assuming DVDs last 60 years (practically), will i be able to get the same quality after so many years? I am assuming that all media degrades over time (so does our precious photos). I know that 60 years from now is a long count, i cant even imagine the data storage possibilities then. Technology is changing so fast.

Mike, i have also noticed my JPEGs fade on several websites, the only possible explanation is that such websites always copy your photos to mirror servers and each time such copies are performed, you tend to lose data as Ken explained.

[Pikachu]

As long as the disk is readable and the file data isn't corrupt, there will be no image quality loss. Copying from one disk or computer to another will not degrade image quality either. It is when you open a file, edit and resave it that you can degrade the image by introducing compression artifact, etc. JPEG is an inherently lossy format. If you are going to need to do multiple edits on a file, you should work from a master TIFF or PSD file as these are both lossless formats, then you can save it as a JPEG after each edit for upload.

[Duffy Pratt]

Also, a limiting factor will be as long as .jpg is a standard format that computers continue to recognize. If I dug around enough, I could probably find some 5 1/4 inch floppies that had some Wordstar documents on them. If I could then find a computer that took 5 1/4 inch floppies, I would then have to do some research to see whether there is still anything that would be able to read the documents. But before I do that, I've got some 8 track tapes lying around that I would like to listen to.

Duffy

[arunap]

Duffy, thanks for some reality check :). You just cant predict technology these days.

[Chief]

Duffy
I have some 5 1/4 and 8" drives if you need em. hhahaha

gordon

[johnastovall]

Originally Posted by arunap

Ken, my thoughts again... Yes i am taking about data loss due to compression or copying..i usually store my original JPEG in my computer harddisk and also take a backup on DVDs. Assuming DVDs last 60 years (practically), will i be able to get the same quality after so many years? I am assuming that all media degrades over time (so does our precious photos). I know that 60 years from now is a long count, i cant even imagine the data storage possibilities then. Technology is changing so fast.

Mike, i have also noticed my JPEGs fade on several websites, the only possible explanation is that such websites always copy your photos to mirror servers and each time such copies are performed, you tend to lose data as Ken explained.

A mirror is not a save. There will be no change in the digital content.

[johnastovall]

To really get a feel and understanding of the basic issue here and not just with jpegs but all digital data, I suggest a reading of Stewart Brand's "The Clock of the Long Now" and checking out the Long Now Foundation.

Or as Jeff Rothenberg says 'Digital Information Lasts Forever - - Or Five Years, Whichever Comes First.'

[Duffy Pratt]

The Clock of the Long Now sounds like it should be a sci-fi novel by Gene Wolfe.

Duffy

[johnastovall]

Originally Posted by Duffy Pratt

The Clock of the Long Now sounds like it should be a sci-fi novel by Gene Wolfe.

Duffy

Or at least the name for Severian's clock....

[pippin]

Duffy - my husband has some software that can read your wordstar files ;)

[lhdvies]

Approximately 4 years ago I scanned a huge nbr of slides and left them on my hard disk. I really feel like IQ has deteriorated some (is this not possible) I have backed them up on a CD and am going to rescan them. I thought they would retain their IQ better on the CD. As you can see, I'm not knowledgeable on this subject and would appreciate any input or advice from anyone who has expertise in this matter.

Arun, I'm not trying to steal a thread here & I appreciate you getting it started-Thks-Leon

[kenw]

"I really feel like IQ has deteriorated some "

this is not possible. digital files, even those scanned from film/negatives do not 'degrade". Media degrades, but the files on them do not. If the media degrades, the images do not become fuzzy, scratchy, dull, washed out or anything else. If the media degrades too much the files become unreadable.

More likely in 4 years your expectations have changed and these no longer match you present talent/standards.