On Wed, May 20, 2009 at 6:22 PM, Graydon <o...@uniserve.com> wrote: > On Wed, May 20, 2009 at 05:18:02PM -0500, Nick Wright scripsit: >> So this new feature that allows you to shift the sensor for composition. >> >> Would that allow you to use the sensor in a similar (though very >> limited) way as a shift lens? Could you use that function to correct a >> slight amount of keystoning in architecture for example? > > The sensor moves left to right, up and down, and rotates around its > centre axis, but all within the focal plane. > > To correct keystone effects, you'd have to be able to tilt the sensor > relative to the focal plane, which I don't think you can do. > > If you *could* tilt the sensor relative to the nominal focal plane, it > opens up some interesting possibilities but it would also cause problems > with figuring out what, exactly, might be in focus at any given time, so > I don't think that will happen. > > -- Graydon >
Actually, you can correct for keystoning via sensor shift, but likely not by a sufficient amount for it to matter. Tilt is rarely used to correct perspective, but rather to use the Scheimpflug effect to control DoF. Keystoning is corrected by positioning the camera parallel to the subject and using shift to move the image circle to get the desired composition. Doing so for more than very minor amounts would require far more sensor shift capability than is present in the SR system. -- M. Adam Maas http://www.mawz.ca Explorations of the City Around Us. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
