Hi,
I am studying in a Film School. We learn cinematography through B&W. We use Kodak 5222 stock. Kodak quotes, 250 as the ASA for that stock. But when we exposed for that rating, it was coming a stop and a half over(In comparison with 11th step mid of a sensitometer strip) in our lab. It implies, it has to be rated more than 500 to get it normal. How this can be possible ? If anyone could help in understanding the problem and solving it, it would be great