Its very simple. If the working diameter of the rear element and the diagonal size (format) of the sensor remain constant, then the further the rear element is from the sensor the NARROWER the corner to corner angle cone angle becomes eminating from the rear element and the deviation from pendicular in the corner of the sensor becomes smaller (better) as the lens is moved away. Do not confuse this angle with the angle of view, they don't have to match and will vary depending on optical design... JCO
-----Original Message----- From: keith_w [mailto:[EMAIL PROTECTED] Sent: Friday, September 09, 2005 2:18 PM To: pentax-discuss@pdml.net Subject: Re: First non DSLR digicam with 10MP APS sensor- contradiction J. C. O'Connell wrote: > Isnt is a contradiction that the lens is CLOSER > to the sensor and its an improvement because that > means the light it hitting the corners of the sensor > at a GREATER angle away from perpendicular which > is BAD (perpendicular being ideal)? I don't understand. The light cone exiting a lens assembly will have a certain value, in degrees, total or half-angle, as you say, from the perpendicular. Move the lens along it's axis toward or further away from the sensor, to exactly cover the corners, it always has the same angle. The only thing that changes is area of coverage. Not the angle of the exiting light bundle. If you insist what you say is true, I have misunderstood you. Please elaborate. keith whaley > ---------------------------------------------------------------------------- > J.C. O'Connell mailto:[EMAIL PROTECTED] http://jcoconnell.com > ---------------------------------------------------------------------- > ------
