Quote Originally Posted by DREW WILEY View Post
Some of this is probably not suitable info for the original poster (overly complicated) ... but in terms
of factual quality, there is a huge distinction between dynamic range of a film ("latitude" per scene
contrast), and that point at which the dye curves start to overlap and contaminate each other.
In many landscape or enviro portrait applications, Portra 160 is going to look undersaturated - it is,
after all, mainly a portrait film - once you boost contrast, either PS or via masking, those otherwise
"minor" color repro errors in non-skintones are going to get exaggerated too, mostly irremediably.
Correct exposure with appropriate color balancing for the actual K temp is going to significant improve (or optimize) what these films are actually capable of. Usually with negs, people just expect
a degree of off-tone mud, so when a "better" film like Portra comes along they yell "Yippee", even
though they could do a lot better job with it if they paid attention to certain details. All you've got
to do is study the published dye graphs to see the truth of this statement. Photoshop won't fix
a serious exposure error, even if the general subject is all there. Two differerent problems.
Could you expand on this as from my own admittedly naive reading, a one stop increase in yellow and a one stop decrease in cyan would mean a huge shift in temperature but only one stop doesn't move significantly up/down the dye sensitivity curve?

Also, as far as I know, Porta is actually a combination of three different sensitivity layers for each colour and hence the film almost works as if it' shifting registers. 3 or 4 stops over exposure and you're into the medium speed register, 8 or 9 stops over exposure and you're into the very slow film register. Does that make sense?

Tim