Let me begin with a little confession – while we like to think of ourselves as immune to them, sometimes we make silly mistakes.
This happened most recently when we began the XRF analysis of some Julia Margaret Cameron photographs to see if the images had been tinted with other elements like gold. Many of you will know that before Instagram and selfies photographs were made with silver salts on paper. So when one is looking for the elements present within a photograph we expect to find silver.
Julia Margaret Cameron took a fantastic photo of Charles Darwin, so we started the analysis with that image only to find the ‘photograph’ contained zero silver. Cue panic from the conservation science team! The analysis was run a second, then a third time (what was the quote about doing the same thing over and over expecting a different result…). We then switched to an image we knew contained silver to see if it was there was something up with the XRF machine – nope, we could clearly see silver on that image. Cue even more panic from the team as thoughts of having to tell people our beloved Darwin image wasn’t what it was supposed to be…
Remember when your teacher would tell you to always read all of the exam question before beginning, turns out you should do that with object lists too… Our Darwin image isn’t a photograph based on silver salts. It is a carbon print and we never spotted this in the internal object description or the object description on ‘Search the Collections’ when we began the analysis. If we had we would never have picked that image to analyse because carbon is too light an element for our XRF to pick up.