What format questions to ask and considerations to make in acquisition of born digital photography collections

Question

Libraries and Archives that collect and aquire the collections of photographers often collect both sets of negatives, proofs, and prints. As photographers move to incresingly sophisticated workflows for managing, organizing and describing photographs in a range of flavors of RAW and digital negative formats what kinds of questions should curators be working through when making decisions about how to ingest and store the collection.

In particular, I would be interested in what questions and considerations a curator should think through regarding 1) sustainability of formats and 2) authenticity to documentation of the process of a particular photographer.

Answer 1

Curators should ask the following questions:

1.     What content do they want to acquire, store, preserve, and provide access to?

2.     Over the expected use lifetime of that content, what are the options available for maintaining the ability to interact with the content?

3.     Which options are the most practical for achieving those goals given the institutional context?

First and foremost the curator should consider what content they want to acquire, preserve, and provide access to. This may include content that (at point of acquisition) can only be presented and interacted with using the RAW files and the custom software that came with the photography equipment that the photographer used. In that case the curator may have no choice but to take those RAW files and ensure they also have legal access to the software used with the RAW files to present and interact with the content being acquired.

The ideal situation for a curator might be if the content that is of interest/value to the curator is able to be stored, presented, and interacted with using TIFF files and widely-used open source software. In that scenario the curator might want to ask the collection owner to migrate data from within the original RAW files into TIFF files and validate that the content is still available when those files are interacted with using the open source software selected for that interaction.  In this scenario the content would likely stand a better chance of being able to be preserved and made accessible in the future for two reasons:

1.     The ability to interact with the content is only dependent on only a set of files that are formatted according to an open, documented formatting standard

2.     The ability to interact with the content is only dependent on software that is open source which means it can be recompiled for use in newer operating systems, and may be more straight-forward to access using emulators

Alternatively, an organization may have previously committed to using JPEG2000 files with a well-supported JPEG2000 interaction application. In that context, using JPEG2000 and its already supported interaction software may be the best solution for the curator to implement for storing, preserving and providing access to the content being provided.

In all of these examples the curator should take great care to ensure that the solution selected does allow for the acquired content to be maintained and accessed. Often, moving between different combinations of format+interaction software can change the content presented to users. This is often not acceptable if that content is what is being acquired (at potentially great expense) and is what is intended to be preserved unchanged.

Answer 2

euanc made a really good point with their first question: what content does the institution want to acquire?  In particular, what does the institution want to document with these materials?  The answer to that question is going to dictate how many versions and formats you commit to preserving.

If the images are documentation of specific places or events and have certain evedentiary value, I would give a certain preference to RAW, DNG, or similar formats because of the extra layer of trustworthiness they provide (i.e. you cannot edit and re-save a RAW file as RAW, so you can trust that it hasn't been altered or re-touched).  If the goal is to document process, version files are what you're interested in keeping.  If the images are more along the lines of art photography or everyday-life documentation, final versions might be all you want to keep.  Of course, available space and the content of the collection play a certain role here, as well.

As far as format choices go, there are lots of tools out there to move between image formats for preservation and access, provided the native format isn't already completely obsolete.  No matter what the nature of the collection, you should (in my opinion) have a preservation TIFF or JPEG2000, JPEG being the runner-up (and a good choice for an access copy).  Whenever possible, I'm a fan of retaining files in their original format as well.  After that, more formats and more versions are documetary icing on the digital cake.

Answer 3

Agree with Sarah about DNG.  But for Trevor: one question is, "How can I maintain the malleability of the raw data from the camera with adequate open metadata to permit its interpretation over time?"  DNG is the answer to that question.  There is a related question that some debate: "Since the main tool for re-wrapping raw camera data is the Adobe Camera Raw application, how can I be sure that it does a good job?" and "When some raw formats, like Nikon NEF, include secret proprietary codes that only Nikon's own software can interpret, what do we lose when we use Adobe Camera Raw?"