Archiving Photos

[TLawrence]

Before starting on the mammoth task of digitising a pile of photo albums (not all aged and interesting from the genealogical point of view, sadly) I would like to set myself some protocols. I want to maintain some consistency on resolution, file format, storage media etc. I would appreciate some advice from those who have gone before in this task.

Is there an "optimum" resolution? Does this differ for colour photos as opposed to B&W? Would it be a good idea to up the resolution at this stage, in case future technology can make use of it?

I do have concerns that since I am recording these photos for posterity, I would like them to be both accessible and usable by posterity. File format specifications seem to change (today's Tiff file doesn't seem the same even as that of 5 years ago, although I don't have the knowledge to understand how or why). Likewise storage media "improve" from year to year. Having already found difficulties in this area (my sister's older machine couldn't open a cd of pictures I sent her) I would like ideas on future-proof storage.

I would be grateful for any suggestions/advice/information anyone might care to share.

Regards
Tui

[Guy Etchells]

As usual the answer starts with a question ;-)
What use do you intend to make of the achived photos?

If you wish to print the photos out then it is best to scan at the highest optical resolution possible, note optical resolution as this does not contain interpolated pixels (best guess using the adjacent pixels).
The reason for this is that simply because printers today cannot handle high resolution photos do not assume they will not be able to in ten - fifty years time.

I have just (before writing this) opened some pictures stored on a cd in 1997 in various formats, jpg, tif, pcx, png, bmp and they all work.
The cd was written on a different computer and has not deteriorated in any way in spite of having a label stuck on it.

Having said that it should be assummed that media will change over time and cds may have to be replaced with dvds or even HD-DVDs (don't bother with dual-layer DVDs at present the disks cost too much and Blu-ray Dual-layer recorders with 50 Gb capacity will be selling by the end of the year)

If you wish to use your archived photos on screen then a lower resolution of around 150-200 dpi will be fine.

Be aware that any digital storage will have to be migrated to new media as the technology advances and the storage media becomes obsolete
Cheers
Guy

[Peter Goodey]

You might be interested to read one of the papers discussing the issues involved in digital archiving on the National Archives website. You should find it somewhere under "Services for Professionals".

[christopher_n_lewis]

I have seen warnings of this sort several times recently. Is it true? I can understand that prolonged sunlight will cause a photograph to fade, and that commercial photocopiers could do the same if running off lots of copies. But if I scan my old family photographs on my home PC scanner, is it going to cause lasting damage, or is this statement based on the precautionary principle?

Christopher

[Peter Goodey]

"Scanning 'ruins old photographs' "

It certainly doesn't "ruin" them. The impact is miniscule compared to what they've already been through. And in any case you only need to scan the picture once and you're done!

[chasdobie]

I think you should scan your photos at the highest resolution you can. Even if you intend to use them only for your website now, who knows what you or your descendants may want to do with them later? If the originals are later lost, then your scans will be the new "originals" and you'll curse yourself if you scanned them at only 100 dpi. I scan all my genealogy photos at 600 dpi in colour, even the black & white ones. Cheers, Chas.

[Ron Lankshear]

Some photos will be important and others "of interest"
Important one save a asTIF and 600 dpi should be enough for future printing etc
Others well could be saved as TIF also for consistency

Decide on naming convention - perhaps a YEAR and a number
Some photos you may want to put a caption on the photo - so I found scanning with a paper at the back gave me a white section on which I could add text in a photo program - perhaps keeping the original as is.
This text is part of the graphics of the photo and unless you keep an original the text cannot usually be changed.
Note" Some photo programs call a caption some words in the properties of a photo which may or may not transport to other programs.

Now I wanted to publish some on web - they need to be JPG and of lower resolution

So we have original TIF , the one with "caption" and the JPG for web - last 2 could be the same

You need a folder filing system for original masters and the various copies
Keep the names the same so you know which to get back to.
Originals also file by year of scan so you can more easily backup to CD and DVDYEAR and a number
Some photos you may want to put a caption on the photo - so I found scanning with a paper at the back gave me a white section on which I could add text in a photo program - perhaps keeping the original as is.
This text is part of the graphics of the photo and unless you keep an original the text cannot usually be changed.
Note" Some photo programs call a caption some words in the properties of a photo which may or may not transport to other programs.

Now I wanted to publish some on web - they need to be JPG and of lower resolution

So we have original TIF , the one with "caption" and the JPG for web - last 2 could be the same

You need a folder filing system for original masters and the various copies
Keep the names the same so you know which to get back to.
Originals also file by year of scan so you can more easily backup to CD and DVD etc
Keep several backups

[coenmfam]

Just to underline what Ron said - TIFFs are a good file format for long term storage. the reason is ....
Lets say you image something and save it as a Bitmap, where in the file is a piece of data for every piece of image ( called a pixel ).
However if you have a photo with lots of Blue sky then you are going to have lots of bits of data saying this pixel is blue. So to compress the size of the file you could say "the next fifty pixels are blue" so one bit of data covers fifty pixels now instead of one.

Now there are different ways of doing this ( compression )
JPEG uses what is referred to as Lossy compression where some data is lost in the compression process, drawback - every time you reopen a JAYPEG some data is lost and eventually the picture quality is degraded. ( unless the JAYPEG is stored on CD Rom where the data cant be altered )

TIFF uses Lossless compression, so no data is lost in the compression process. Drawback TIFFs are usually bigger than JPEGs. Sometimes a TIFF will be bigger than the Bitmap you are trying to compress - in which case a JPEG might be a better solution.

So you need to be flexible in the file formats you use but generally TIFF is the better option.

As has been said before 600 dpi is good for archives, and you really won't notice the difference between 600 and 1200 dpi, and for your information your computer screen is only good to 75 dpi and you are generally wasting ink printing about 300 dpi.

The life span of recordable CDs varies with CD-RW having the shortest life span, somewhere around 2 -3 years before the data starts to degrade.
CD-R has a slightly longer lifespan but only about 5 - 7 years before data starts to degrade. Pressed CDs such as music CDs you buy in shops are supposed to have a lifespan of many years ( 50 + )
Another alternative is to back up to an external USB Hard Drive, however this is not fail-safe either and Hard Drives dont like being next to things magnetic and they dont like being dropped or thrown around.
Moral of the story back up to more than one type of media any data you seriosly wish to archive.
Its a bit like putting a dollar each way on both horses in a two horse race.

hope this helps
Neville

[TLawrence]

Thanks for that input, Neville - it confirms my plans as far as using tiff format is concerned, but I am a bit surprised at the short lifespan of CD-R. I shall have to rethink the plans for archiving, as I was hoping to use that for long-term storage. Does it make a difference how often one accesses the archived images?

Regards
Tui

[coenmfam]

Well, it seems that I may have been wrong about the lifespan of CD-Rs ...
sort of ... well it depends on who you talk to.

CD-Rs can have quite a long useful life time but with one caveat
They must be permanently stored in the dark, at 25 deg C @ 40 % humidity

Kodak claims a lifespan of over 200 years
TDK claim over 70 years

again claiming 70 - 200 years as long as they are stored correctly
30 years for CD-RW
again under perfect & ideal conditions ( Dark, Dry & Cool )

ON THE OTHER HAND

some brands fall over after only two years

The moral of the story I suppose is to
*research a top quality brand, and store your CD-Rs under the said ideal conditions
* Use more than one type of medium for storage
* Dont use sticky labels on CDs ( wish I'd known that earlier myself )
* Consider static memory as an option ( compact flash drives etc )
* Use Gold CD-R

some more good articles

hope this helps
Neville