There is a formula to determine the distance (altitude). I/F = G/A I is image size on film/sensor F is focal length G is size of object on ground A is altitude
Plugging in some wild guess figures of .080 I, 8" FL, and 200 ft long plane I come up with 20000 ft. Normally contrails below 25000 ft are not normal but possible, and absolutely my figures are wild guesses, but it's at least 20,000, probably 30,000 feet up. Walt On 6/6/08, William Robb <[EMAIL PROTECTED]> wrote: > > ----- Original Message ----- > From: "Doug Franklin" > Subject: Re: Airplane II, The Sequel > > > > William Robb wrote: > > > >> ... Tokina AT-X 80-200/2.8 > >> > >> http://users.accesscomm.ca/wrobb/temp/airplane.html > >> > >> I don't know how high those things fly, but its a few miles away from me. > > > > I don't know how high that one is, but it's considerably lower than the > > max cruise altitude for that aircraft type if you got that much frame > > filling with a 200. :-) Some of those big people haulers can cruise > > close to or over 40,000 feet. > > The shot I posted was quite a bit of a crop. > Heres the full frame, resized for the web and showing some interesting > blotchiness. > http://users.accesscomm.ca/wrobb/temp/full9861.jpg > > William Robb > > -- > 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. > -- 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.
