Film Processing Question

As a wedding guest (not the official photographer - and, in fact, "chased" by the official photographer on a number of occasions) I shot a few rolls of Fuji NPZ-800. I intentionally shot it at ASA 640. My question is, do I now have to inform the lab that they should be processing at 640 or do I not inform them and get it processed at 800?

With print film, you have such a wide lattitude that you really don't need to have it pulled to iso640 in order to have it developed. I would just process it at 800 and save the money from having to pull it.

As a rule, you adjust the iso of print film to over expose or under expose due to the characteristics of the film. Then you process normally.

Loren

I don't have experience with Fuji neg films, but with Kodak Portra I'd recommend overexposing it a little (640 would be good for 800). It's much better to overexpose than underexpose even a little, and this gives you a little assurance. Process it at 800 and you'll be fine.

Chased?

Yeah when I started reading this I thought you were going to go on to say that you had delibertaly over exposed it at 640, I once read that its a good idea to slightly over expose fast film as it controls the grain a bit, although I hear that film is so good its unessasary. But with the latitidue of colout neg its not worth pulling, I once rated a good portion of a roll of Kodak Ultra colour 400 at 500 and I couln't tell the differnce.