wickerprints wrote:
Is it me, or does the fisheye zoom MTF make no sense at the wide end? If it\'s 8mm circular, there shouldn\'t *BE* any MTF beyond 12mm because that\'s the radius of the image circle. So, what is the curve describing?
alundeb wrote:
Yeah, they forgot to set the limits in their computer simulation model or what?
That still wouldn\'t explain it, because in a computer model, even simulated incident rays could never fall outside of the image circle. There would be nothing to simulate. In other words, if the ray tracing simulation showed light falling outside the 12mm circle, then where did those rays originate? Certainly it could not have been modeled as passing through the lens!
Whatever is the case, I am sure we are looking at some bogus MTF results. That entire chart is suspect to me. The only plausible explanation I can think of is that the x-axis scale (image height) actually ranges from 0 - 12mm, and they simply neglected to label the axis correctly.
Aug 26, 2010 at 07:09 AM
Previous versions of wickerprints's message #8787877 « New lenses »
