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Old Sep 15, 2003, 5:42 AM   #1
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Default Best method of archiving photos ?

I have been having fun scanning some of my old slides and negs with our Canon FS 4000 US scanner & Vuescan. But considering we do have storage room limitations on our HDD, should I archive the files in:

1/ Tiff, 48bit, 4000dpi averaged down by 2, no compression.

or

2/ Tiff, 24bit, 4000dpi no averaging, no compression.

Is there any known notable quality difference between the two methods.
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Old Sep 15, 2003, 6:36 AM   #2
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Don't Archive to a HDD - it might crash one day! For negs and slides if the processing time is acceptable, use the highest res. you can get then archive to CD write once or data Dvd.

Make sure your files can be read in other devices, never swap out/upgrade your reader unless sure your archive can still be read.

When new storage formats and media start to replace yours, consider copying your archive across. Always make 2 copies and keep one copy in a friends or relatives house. VOX
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Old Sep 15, 2003, 9:15 AM   #3
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Others can correct me here, but I wonder why you are not using compression?

Tiff compression is loss-less. It is not like jpg. As far as I know, there is a standard for Tiff compression so you shouldn't be stuck with only one application being able to read it. Most images can compress a lot, which should save you time and space when backing up.

Eric
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Old Sep 15, 2003, 10:41 AM   #4
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Eric, TIFF is not compressed, which is why it's lossless. With photos and the random structure of data you have to go to JPEG, but a 2 or 3 to 1 compression of file size will still be higher quality than most camera settings. We mustn't forget that errors will enter at the scanning stage so using some compression is a reasonable choice, but watch out for noise.

If one wanted to be pedantic about archiving, a bitmap TIFF file might be more easily read in 50 years time than a JPEG requiring a decoder. But I assume this isn't museum stuff.

I went through similar thinking when presented with a deceased relative's photo's - archive to digital and dump the slides. In the end I decided to scan to improve in post and show on a screen for the family, but once removed from the slide carriers and the slide box, the transparencies stored in plastic wallets really didn't take up much space.

With prints, I scanned everything, but only kept the prints that had identifiable subjects or historic interest. This is an area to be careful with. Older people usually write the names of subjects or places in photos on the back of a print. When scanning, ensure that this info is also stored. Perhaps this is a good reason to add notes to pictures, it really helps for the future. I use ACDsee to organise my pics on CD's.

In the end, archiving to electronic storage was more based on exposing the old slides to curious relatives, than a need to save storage space. VOX
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Old Sep 15, 2003, 12:49 PM   #5
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TIF has had extentions for compression for over 10 years. I was storing compressed TIF when I was in college (oops, I just showed my age!!) What I don't know is if this is program dependent (and therefor shouldn't be used) of it this is some part of the TIF standard (or an extention of the standard) and therefor should have some broad support.

If you run irfanview, and you save as TIF, it offers to store it compressed. It lists:
None, LZW, Packbits, JPEG, ZIP

LZW & ZIP are lossless. Heck, GIF is a lossless image compression format. So it isn't inherent that compression = data loss for images.

I do agree, though, that a non-compressed TIF should be very easy to reverse engineer and decode in 50 years. GIF uses runlength encoding, so it's fairly simple to redo, but TIF is even easier!

Eric
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Old Sep 15, 2003, 7:46 PM   #6
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Thanks for all the ideas.

The matter of compression is simply an add on to the original question that remains unanswered ?

48bit 4000/2
or
24bit 4000

I do burn on to CD's only as a back up but I use PNG for that. When I can afford a DVD burner then I will back up the primary archive that is in Tiff. CD's do not hold enough data to store many photos.
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Old Sep 16, 2003, 1:11 AM   #7
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eric is correct. even the RAW images of my camera start off at 9-11MB compressed and then result into 30+MB Tiffs

http://www.adobe.com/support/techdocs/20f02.htm

http://www.ftgimp.com/help/C/filters/tiff.html
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Old Sep 16, 2003, 2:08 AM   #8
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Default Re: Best method of archiving photos ?

Quote:
Originally Posted by xcaddict
Is there any known notable quality difference between the two methods.
Why not do the experiment, try both methods on a favourite shot, and then inspect the results at high magnification in your image viewer (i.e., pixel by pixel), and see if you can see the difference?

I myself archive as jpeg at approx "13/100 compression", "87/100 quality" rather than tif, because I can't see the difference at a pixel level. This results in approx 1.4MB for a 5Mpixel image, about 600-750KB for a 3Mpixel, and about 1.7MB for a 25MB 2700dpi (c.3600x2400) negscanned image.

In the event you wished to rework the archived image in detail at very high quality in future, the jpeg compression might conceivably cause minor problems. Therefore tif might be appropriate for specially prized shots that you or your grandchildren might wish to use in a big way in future.

The biggest problem, as others have said, is transferring all the data to new storage media as they come along every few years. If you're serious, you'll have to do this several times as you get older. It'll become more & more of a burden, so compressing the files is a good idea so that it's quicker and easier .

I'm still putting doomed colour slide shows via a doomed Video8 camcorder on to doomed VHS tape, myself. REALLY GOOD slides get filmscanned, twiddled, and then jpegged on to CD-R.
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Old Sep 17, 2003, 3:24 AM   #9
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Just as an aside, from the field of (digital) image processing, the terminology has been that image compression is always lossless, and lossy compression is referred to as "image reduction".

This might help avoiding some confusion.

I also struggle with the problem of which medium to choose for archiving as there are no permanent solutions known to me at this time (permanent defined as to last for a lifetime, and easily restorable during this time). DVD (data) storage will have to do for now, I guess (it will last a reasonable time before having to convert it to a new storage format). Will the filing system format used last as long I wonder?

Having said that, anyone any ideas on how long the jpg standard will last? Any new developments in the area of image formats lately?
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Old Sep 17, 2003, 4:29 AM   #10
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It's difficult to predict the life of a coding scheme as we are still on the curve of improvement and you shouldn't rely on backwards compatibility promises. In the early days, coding schemes used for transmission used heavy processing at the coder and light at the decoder. Now that hardware has advanced to 2Ghz + levels, more sophistocated higher quality more processor intensive compression algorithms can be developed.

The life of a compression scheme will be as long as you can find software to decode it or maintain your existing hardware and software - remember you only have an intermediate format, not a useful image until printed. It's just the same with tape. With digicam, most of us have a closed work flow environment - we can choose to maintain an older system and still get prints. Perhaps we should be talking about archiving our PC's! Also as we get older, our ability to run complex computer systems will decrease. At 80 years old, a bunch of pics in an album may be more accessible than firing up a pc.

Incidentally, when I excluded TIFF as a compression format earlier, I did so because the compression alternatives rely on repetition of the same data to work, this rarely happens in images where data is virtually random. So I think you'd find a compressed TIFF file no smaller than uncompressed (except on a black or white frame).

For the most valuable image I'd still choose uncompressed bitmap - but film, due to the simplicity of the 'decoder' required, still remains timeless! Try finding, installing and running real DOS programmes on a modern machine as I did recently and you'll get the idea. Cheers VOX
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