What is this "to my list from the i3a" you speak of ? There are so many guesses as what is Agfa Vista plus 200 that I've given up (h'mm I wonder if anyone has written to Fuji and got an honest answer
) , well someone by hearsay (not recent), on the net (no link), has compared Vista 200 and 400 and says it's the same film
...plausible as Ilford did that fiddle about 40 years ago rating their FP3 (or whatever it was then) from 64 to 125 ASA and of course sold more film compared to other makes that were rated slower.
Brian, the i3a (International Imaging Industry Association) is/was an organisation that supervised film and photography standards, and amongst other things they were responsible for the DX number system. The DX number and barcode identify the film type to processing machinery so that the correct profile etc can be applied, and from these you can work out what film is actually in the cartridge by converting the number to two identifying 'parts'. The i3a publish a list which says what these numbers actually correspond to. Manufacturers were assigned DX numbers to use for their films, and the list was updated periodically to say what they corresponded to.
The simplest way to find out what it is is to put the number into the DXn simulator (
http://www.imageaircraft.com.au/DXsim/ [where it says "barcode" and then press enter]) and get the two DX number parts - the simulator will also give what the film is automatically if its in its database, but it uses the older 2004 list so a lot of newer films are not in it. If you then look on the i3a list, it will identify what film the two number parts correspond to. It also works with the film edge code [the little bars] as they correspond to the same thing.
Unfortunately the list is no longer on the i3a's website (which appears to have gone as you're now directed to a project about standardising camera phone quality), but I have a copy of it that I saved before it went. I would attach it, but PDF files can't be attached on here.
The advantage of this system is that you can identify with near certainty what the film is as otherwise the wrong profile etc would be applied during scanning/printing by the processing machinery, which would likely screw up the image quality. I've taken the numbers off 4 Vista 200+ rolls and all of them correspond to Fuji C200 (which makes sense as its marked as made in Japan and Fuji is the last Japanese film company left), and both codes I've been told for the 400+ correspond to Superia 400. I seriously doubt that the 200 and 400 are the same because as I mentioned, there are no real 'cheap' 400 speed emulsions, they have different DX numbers and the image quality would probably suffer greatly if it was 200 re-labelled as 400. The only reason for Ilford uprating HP3 and FP3 in ~1968 was because the 1 stop 'safety factor' was removed from the ASA/ISO specification due to improvements in metering - all of the other film companies followed suit with Kodak also rating Tri-X as 400 rather than its original 200.
Remember that 'Agfa' is not actually 'Agfa' any-more - any Agfa films are just re-branded films from other manufacturers as Agfa-Photo don't make any film so the Vista+ emulsions are nothing like the old proper Vista ones which were exclusively Agfa's. (To avoid confusion, 'Agfa-Geveant' is another company that makes aerial and industrial films - it was spun off from its parent company shortly before Agfa went down in 2006 - many of which are rebranded as Rollei films amongst others)