Continuity of data, chain of evidence

[nomandera]

The title is a bit grandiose but something that bothers is data continuity. In simple terms I "just" want to know that i have all images and that these images are unadulterated no matter what.

You would think this would be simple but I find that many tools deem it acceptable to make changes to images. This is normally restricted to embedded meta data but can also be file paths, timestamps and on rare occasions the actual image itself.

Photonix is not one of these applications and that was one of the reasons I was drawn to it. The commitment to XMP is also IMO the right approach and potentially the future of how everyone should do it (caveat: XMP format is a bit too wild west/black art to make this an easy win).

So to the topic at hand, I currently using a combination of scripts, automation and human effort in an attempt to make absolutely sure I have a master copy of all images. I won't go into too many details as my kludge is far too specific but the general concepts of what I am attempting to do.

• Image enters the system (multiple users)
• Images are organised into "/pictures/masters/year/month" in a way that file timestamps are maintained. Files are organised in this way purely because over time having no structure at all just wont work and this dated structure is MVP and scalable. All real organisation is done via tagging.
• Create CRC files so that at any time I can confirm the master is identical to the day it was submitted
• Create XMP files to allow for tagging and other manipulations

This is the point where images would traditionally be introduced to Photonix. Tastes will vary where some would just allow direct access to the images, others the same but RO and yet others would want a separate copy.

There are countless variations here but it occurs to me one reason there are so many variations is because of the lack of "chain of custody".

Maybe Photonix should maintain the chain of custody from the very first step as a prime design tenet.

Certainly its an interesting discussion.