In article <48rbfl$77c@mark.ucdavis.edu>, auyeung@cs.ucdavis.edu says...
>Suppose I have a white subject, and the camera partial/spot meter
>suggests to use 1/60sec f/8, how many stops should I increase
>to make white look white?
>For color negative (Fuji G100), it seems that +2 is about
>right. For B&W negative (TMax 100), it seems that +4 is
>about right. How about for slides (Sensia 100)? Since the
>latitude for slide films is narrower than negative films in
>general, I'd imagine +1 or +1.5 is enough?
Try 1 2/3 stops for a very light grey, to 2 stops for a near white
(maybe 2 1/2 for pure white). (1 1/2 to 1 2/3 stop over snow reading works well for me to render snow a convincing white [with texture
still evident, while keeping other parts of scene nearly right].)
Hope this helps.