The FOV would be the same for both 400mm lenses when used on the same 24x36 sensor. You seem to think that a 645 400mm lens is a different magnification from a 35mm 400mm lens when both are used on the same small 24x36 sensor. The magnification and FOV from BOTH 400mm lenses would be the same when using the same 24x36 sensor in both cases. Thus using the 400mm 645 lens makes no sense at all with a 24x36 sensor as compared to a 35mm 400mm lens which would be smaller, lighter, cheaper, and probably even sharper for other reasons to boot. JCO
---------------------------------------------------------------------------- J.C. O'Connell mailto:[EMAIL PROTECTED] http://jcoconnell.com ---------------------------------------------------------------------------- -----Original Message----- From: Bill Owens [mailto:[EMAIL PROTECTED] Sent: Friday, December 12, 2003 5:13 PM To: [EMAIL PROTECTED] Subject: Re: New Pentax DSLR next year The FOV would be the equivalent of a 600mm on a 24x36 sensor. Bill ----- Original Message ----- From: "J. C. O'Connell" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Friday, December 12, 2003 5:08 PM Subject: RE: New Pentax DSLR next year > Your talking something different here. > The inital suggestion was that a 400mm 645 > lens would be much different than a 400mm 35mm format > lens ON THE SAME 24x36 DSLR CAMERA! Not true. > jco > -------------------------------------------------------------------------- -- > J.C. O'Connell mailto:[EMAIL PROTECTED] http://jcoconnell.com > -------------------------------------------------------------------------- -- > > -----Original Message----- > From: Bill Owens [mailto:[EMAIL PROTECTED] > Sent: Friday, December 12, 2003 4:57 PM > To: [EMAIL PROTECTED] > Subject: Re: New Pentax DSLR next year > > > Granted, but you would have less of the image circle visible on a 24x36 > sensor than on 645 film. IOW, if your main subject is two inches high, it > will be two inches high on both formats, but the entire subject would be > visible on 645 film and less than 1/2 of it on 35mm (assuming landscape > orientation). > > Bill > > ----- Original Message ----- > From: "J. C. O'Connell" <[EMAIL PROTECTED]> > To: <[EMAIL PROTECTED]> > Sent: Friday, December 12, 2003 4:44 PM > Subject: RE: New Pentax DSLR next year > > > > 400mm is 400mm no matter what sensor > > or film format. a 400mm 645 lens wont look > > any different than a 400mm 35mm format lens on > > THE SAME 24x36 dslr. There would be no > > logical reason to use a 645 400m lens > > on a 24x36 dslr vs. a 35mm (24x36) format > > 400mm lens on a 24x36 dslr. There IS NOT > > an "apparent" optical difference if both > > lenses are the same 400mm FL! > > > > jco > > > > -------------------------------------------------------------------------- > -- > > J.C. O'Connell mailto:[EMAIL PROTECTED] http://jcoconnell.com > > -------------------------------------------------------------------------- > -- > > > > -----Original Message----- > > From: Bill D. Casselberry [mailto:[EMAIL PROTECTED] > > Sent: Friday, December 12, 2003 3:47 PM > > To: [EMAIL PROTECTED] > > Subject: Re: New Pentax DSLR next year > > > > > > "J. C. O'Connell" wrote: > > > > > huh? a 400mm lens designed for 645 isnt going > > > to give any bigger image magnification than a > > > 400mm designed for 24x36 but it would be larger > > > and heavier and costlier. No way Jose! > > > > yeah, sure - by straight optical physics > > > > but the actual effect is a seemingly longer reach w/ > > a given focal length on a smaller "film gate" exactly > > like everyone is so happy w/ when putting a tele onto > > their StarKist w/ its less than 24x36 sensor. The end > > result (granted, it is merely a *cropping factor* like > > on would get w/ an enlarger) is an apparently longer > > lens - period - ... and that's all that matters. > > > > Bill > > > > --------------------------------------------------------- > > Bill D. Casselberry ; Photography on the Oregon Coast > > > > http://www.orednet.org/~bcasselb > > [EMAIL PROTECTED] > > --------------------------------------------------------- > > > > > > >
