P. J. Alling <[email protected]> wrote: > Reciprocity is corrected by longer exposures. I n some, (used to be > all), color films the different emulsion layers require different levels > of correction, as the layers have different reciprocity curves, which > caused color shifts.
Once you are at 30 secs or over, this all becomes quite academic. Besides, most night scenes are illuminated by artificial light sources where the usual rules governing colour rendition with daylight no longer apply. Artiificial sources have totally different colour temps and most produce a non-continuous spectrum. Combine various types - say neon, incandescent, sodium, and xenon - in one frame and you're in colour correction hell. There are no manufacturers' charts for that. All this has however become a lot more manageable since we're scanning analog colour film rather than printing it directly in a conventional lab. Selective colour correction can do miracles in such cases. Long story short: use colour neg film, get your exposure right, overexpose if in doubt, and care about those colours later on in digital processing. Ralf -- Ralf R. Radermacher - DL9KCG - Köln/Cologne, Germany Blog : http://the-real-fotoralf.blogspot.com Audio : http://aporee.org/maps/projects/fotoralf Web : http://www.fotoralf.de -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
