"Don't think and drive!" :-) Larry, as far as the glass is concerned, - there are more parameters/constrains than just lpi: the maximum aperture, the minimum aperture (which becomes important for the small sensor sizes, - as you end up getting diffraction), performance at different apertures, etc. More over, the parameter space that determines lpi is multi-dimentional. Those other parameters (e.g. the minimum aperture), - also can affect lpi. Things become even more complicated for zoom lenses, where the parameter space blows up by probably an order of magnitude.
On the side of the camera, - it is also not just the resolution of the sensor. (E.g. high ISO performance can be separate from the resolution optimization.) So, optimization is not (and should not be) done by just using lpi vs. cost alone. Igor > Mon May 17 11:37:04 CDT 2010 > Larry Colen wrote: > I have the bad habit of thinking about the design of camera equipment > when I'm driving. For a mass market system, one would expect that the > engineers would figure out how much resolution is needed, and design the > system around that. Another option is to place the constraint on the > size of the sensor, and try to optimize there. > > If we can assume that Moore's law is going to hold on sensors, for at > least a few more iterations, then for long term planning, sensor cost is > not going to be an issue, and it might be best to optimize system design > on the glass. Lens quality has improved over the years, but I'm > guessing that the improvement over time is more linear, or logarithmic > rather than the exponential improvement (2dB/year) of Moore's law. > > The sharper a lens (lines per inch) the more expensive it is to produce. > Likewise the larger the sharp area of a lens, (24x36 sensor vs APS) the > more expensive it is to produce. There are also physical limitations to > the resolution, it can't get any better than the wavelength of light. > > So, for ultimate system resolution, is there a sweet spot for lens > design where you get the best lines per inch times sensor area for the > least cost? Or is it simply a case that as far as glass is concerned, > it's always cheaper to get the same total resolution with a bigger > target area? > -- 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.
