If the the resolution of the lenses (and all other optical qualities as well), were equal, and assuming that both lenses met or exceeded the resolution of the sensors. If you took a 10.2 megapixel 2:3 aspect ratio crop from the center of the 14.6MP image, you could make prints with roughly the same resolution from each. If you crop the 14.6MP sensor with a 300mm lens to the same AOV as the 10.2MP sensor with a 400mm lens you will have somewhat more resolution, (I'm not sure how much I haven't done the math in detail, just enough to know that an equivalent crop will contain more MP.
John Wittingham wrote: > Thanks for the responses, OK I think I need to re-word this altogether, > Pentax K10D 10.2 Megapixels fitted with 400mm lens v's Pentax K20D 14.6 > Megapixels fitted with 300mm lens, assuming both lenses produce excellent > results, which combination would give the bigger print size from a crop at > the center of the frame if yoy were for example shooting a distant bird at > the same distance in each case? > > Regards, > > John > ________________________________________ > From: [EMAIL PROTECTED] [EMAIL PROTECTED] On Behalf Of J. C. O'Connell [EMAIL > PROTECTED] > Sent: 27 June 2008 13:18 > To: 'Pentax-Discuss Mail List' > Subject: RE: Sensor resolution V focal length.......... > > Are you trying to say that there will be no resolution loss in using a K20D > with a shorter lens vs a K10D with a longer lens if the AOV of the image > is kept the same via cropping the K20D image? The REAL sensor size of the 2 > cameras > are NOT EQUIVALENT if you crop the K20D image and use a shorter fl lens. > > JC OCONNELL > [EMAIL PROTECTED] > > > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of > Anthony Farr > Sent: Friday, June 27, 2008 8:03 AM > To: 'Pentax-Discuss Mail List' > Subject: RE: Sensor resolution V focal length.......... > > > The crop will be the same from K10d to K20d, because the crop factor is > related to the sensor dimension not its resolution, and the two cameras have > equivalent sensor dimensions. > > The K20D shots will "enlarge" more at 100% view, simply because it has a > greater pixel density. This doesn't mean anything other than that your > monitor resolution (e.g. 1024 x 768)represents a smaller patch of the K20ds > sensor compared to the K10d. The >>whole<< picture will have the same field > of view for the same lens when the two camera models are compared. You > wouldn't print at 100%, the only practical use for this view is when > performing some editing functions, and for pixel peeping. > > Regards, > Anthony Farr > > >> -----Original Message----- >> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf >> Of John Wittingham >> Sent: Friday, 27 June 2008 8:59 PM >> To: [email protected] >> Subject: Sensor resolution V focal length.......... >> >> 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. > > > -- > 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. > > -- Vote for Cthulhu. Why settle for a lesser evil... -- Dr. Jerry Pournelle -- 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.
