Chelin Miller kindly shared her film of ambrotypes (collodion on glass) being made at the NPG: it’s not the same as tin types (on metal). This includes me – at 1.38 – as one of the people talking about taking part at the NPG:
I’ve already written something about this here – including more details of how ambrotypes – on glass – are made. Up above is the (upside down) image the photographer sees. And here’s my final glass negative:
Of course I’m still interested in this! I’m going to learn how to actually make tin types (on metal) and ambrotypes (on glass) with Almudena Romero on 8 Sept.