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Photo courtesy of Kellan Elliott-McCrea
Long-term storage and preservation of your digital photos is not as simple as placing them in one location and leaving them until you need them again. You must take an active role in the management and storage of digital images in order to give them the best chance for long-term preservation.
Select your important files:
- Evaluate your images to decide which ones you really want to keep for the long term.
Organize your files:
- Renaming images with descriptive names won’t necessarily make the images last any longer, but it makes retrieval much easier.
- It can be time-consuming, though, particularly for large collections.
Save files in formats that are optimal for long-term preservation:
Choosing the appropriate format can be a critical part of preservation. Some formats cast away bits of information as part of the creation and compression process. Here are the most common formats with some advantages and disadvantages. The most widely accepted archival formats are marked with an asterisk:
- JPEG – Joint Photographic Experts Group
- Advantages: very common format, can be used with almost any device or software meant to work with images, relatively small files, amount of file compression is controllable
- Disadvantages: It discards some information every time it is saved
- *JPEG 2000 – More preservation appropriate version of the JPEG
- Advantages: Lossless, allows use of same image as master and derivative
- Disadvantages: complex format to use, not as compatible with various software
- *TIFF – Tagged Image File Format
- Advantages: common format, uncompressed files are lossless
- Disadvantages: large files that require more space to store and move, doesn’t work with as many devices as JPEG
- PNG – (Portable Network Graphics) an open format designed to replace GIF for web site images – it has become used for wider applications as wel
- Advantages: Lossless compression that restores an image to its exact original characteristics and supports large number of colors (as opposed to GIF), non-proprietary
- Disadvantages: older software & hardware may not be compatible with PNG, is still larger than a JPEG file
- RAW – Generic name for formats developed by camera manufacturers with many variations. Digital Negative was developed by Adobe as an attempt at having a universal Raw format.
- Advantages: keeps exactly what was picked up by the camera sensor, relatively flexible and small
- Disadvantages: proprietary formats, updated often, incompatible with other manufacturers’ versions, format changes rapidly and updates are not always backwards compatible
Make copies and manage them in different places:
- Keep multiple copies of your images in different locations and on different media forms to ensure the best chance of long-term preservation.
- One copy may remain on your computer, but putting several other copies on separate media such as DVDs, CDs, portable hard drives, thumb drives or Internet storage will be the best protection against loss.
- Store copies in different locations that are as physically far apart as practical. If disaster strikes one location, your images in the other place should be safe.
- To be as safe as possible create 2 copies of the image. Put one away as your master copy without modifying it at all and use the other one for your color-correcting, cropping, emailing, etc. When you need another copy to manipulate, make a copy of the master file and work with the copy. Many people may keep TIFFs as their master files, but created JPEGs for emailing, presenting, etc.
Long-term storage is a key element in preserving digital images. It is important to realize that no storage medium is permanent in the digital environment. Any storage medium used will require some maintenance to keep its contents viable for the longest period possible.
Currently the most common media used for long-term storage are:
- CD/DVD – common form of storage and cheap. (Optical media will face longevity issues, so this should be a considered a short-term solution)
- USB drive – very common storage method and relatively inexpensive
- External hard drive – Holds large volumes of material and is a bit more expensive.
- Internet/Cloud storage – generally subscription-based for a respectable amount of space
Check files and refresh storage media on a regular basis:
- Check your saved files at least once a year to make sure you can read them and that they are still relevant and worth continued archiving.
- Create new media copies every five years or when necessary to avoid data loss.
Migrate files to newer formats if needed:
- Attempt to stay current with major shifts in standards, software, hardware, platforms, and formats to ensure that your files are in a common, readable format.
Last Edited: 8 May 2012