I have started, just for fun, the compilation of the DX emulsion numbers that can be found on 35mm cartridges. The DX emulsion mumber is not the DX speed code, but it's a 6-digit number that identify the emulsion and it is found under the DX speed code (the conductive squares) both in a barcode form and a numeric form. http://en.wikipedia.org/wiki/DX_number I have created a google doc which is public on the internet at this address: https://docs.google.com/spreadsheet/ccc?key=0Ak25iVXE6qSJdFFObDBySlFqYjdUVVphUWVfbjlGT2c&usp=sharing Feel free to contribute. I am not doing this for profit or anything else. I just want to collect as many emulsion numbers as I can - I believe this will be useful to understand OEM/rebranded films where they are actually coming from. I have, to this purpose, added an Analysis tab - here you will find the films grouped by emulsion codes. Very interesting. There are a couple of things that I immediately noticed: - Fomapan and Ferrania films have the same emulsion code. This is clearly something wrong (the numbers are correct though). - Fuji Velvia 50 and 100 have the same emulsion code, and so have Fuji Neopan 400 and Acros. There are other confirmations like Arista 400 being TriX 400, etc.