Archived posting to the Leica Users Group, 2009/09/24
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]leo wesson wrote: >>> maybe, it's confusing! it's what we called it in school..... http://en.wikipedia.org/wiki/Circle_of_confusion Leo Wesson Photographer/Videographer 817.733.9157 www.leowesson.com On Thu, Sep 24, 2009 at 6:00 AM, wildlightphoto at earthlink.net < wildlightphoto at earthlink.net> wrote: > leo wesson wrote: > > >>> > amount of lens movements required is the deciding factor on what type of > lens to buy. larger circle of confusion=more movements > (tilt/shift/rise/fall) > <<< > > Wouldn't that be "image circle", not "circle of confusion"? > The Circle of Confusion (CoC) is the image on the film plane of a point of light on the subject. Ideally, neglecting diffraction effects, the CoC for a correctly focussed point on the subject is also a point on the image plane. The CoC is bigger/less pointy when focus is off or when the lens has has more abberations. The image circle is the size of the image the lens can make at the film/sensor plane. Most lenses for 24mm x 36mm cameras have an image circle that covers the 24mm x 36mm area, and little or no more. A bigger image circle allows more shift and/or tilt. Doug Herr Birdman of Sacramento http://www.wildlightphoto.com -------------------------------------------------------------------- mail2web.com ? What can On Demand Business Solutions do for you? http://link.mail2web.com/Business/SharePoint