On Oct 16, 2011, at 9:22 AM, Matthew Hunt wrote: > On Sun, Oct 16, 2011 at 12:06 PM, Larry Colen <[email protected]> wrote: > >> I read something about the astrotracer not working perfectly with >> rectilinear wide angles because the stars at the edges leave traces. > > Are you sure that this issue has to do with rectilinear lenses, specifically?
No I'm not sure, something of that sort was mentioned in that "night photography" photo book that was just posted. > > What comes to my mind is this: The correct movement to track the sky > is rotation about the celestial pole. The astrotracer tries to > approximate this motion using the sensor movements available to it: > rotation about the sensor center, plus translation. I think that for > wide fields of view, unless the sensor is centered on the pole, the > tracking motion is going to be wrong at the edges, no matter what the > geometric projection of the lens is (rectilinear or fisheye). That may well be possible, They need different tracking at different parts of the sensor. Even so, the question remains, in general, are you better off with a rectilinear super wide, or doing the correction in software? > > -- > 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. -- Larry Colen [email protected] sent from i4est -- 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.
