More on FAQ #405
405. Why doesn’t TCQ spell out which specific “light”-related changes are allowed, the way allowable non-“light”-related changes are carefully spelled out?
(This is a reference to TCQ’s Allowable Changes; “light-related changes” are #10 on that list.)
For almost any common kind of “light”-related change, it is possible to picture a situation in which that change would be necessary for the photograph to meet Q7.
For example, there aren’t any “light”-related changes more radical than changing every color in a photograph to its opposite — and yet that is what has been needed to produce a trustworthy result from billions of photographs recorded onto a film negative.
(Converting “negative” images to “positive” is of course allowed by TCQ.)
When discussing allowable “light”-related changes in TCQ photographs, what matters is not the nature or degree of the change but whether the result meets Q7.