John, You are on the right track but it's a bit early (AM) to discuss this for my brain. The 100% crop from a 400mm will be bigger than the same photo with a 300mm. (Need geometry/trig to figure by how much exactly...) With the K20D vs the K10D, the 400mm will give you 14 megapixels instead of 10. So a 600 x 900 pixel "100% crop" of 540,000 pixels on a K20D will show about the same area as 385,700 pixels on a K10D, or 507 x 761 pixel image. It looks like an 18% enlargement on the K20D. Regards, Bob S.
On Fri, Jun 27, 2008 at 5:59 AM, John Wittingham <[EMAIL PROTECTED]> wrote: > I'm in need of some longer glass, longer than 300mm. It occured to me the > other day that the crop of a given area of a frame would be consirerably > bigger the more resolution you have from the sensor of the camera viewed at > 100%. So I'm thinking 400mm on the K10D would be approximately 33% bigger at > the same crop as it would be from 300mm viewed at 100% right? > > So if I'm using a K20D how much bigger would a crop of the same subject shot > with the K10D be viewed at 100%, could I substitute pixels for focal length > providing the lens resolution is up to the job? Are there any downsides other > than the obvious differences when using a shorter focal length such as DoF? > > Regards, > > John > > -- > 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.
