Thanks, Mark you just answered a question I'd held for some time re Ansel and the f64 club.
Jack ----- Original Message ----- From: "Mark Roberts" <[email protected]> To: "Pentax-Discuss Mail List" <[email protected]> Sent: Friday, April 17, 2015 8:59:54 AM Subject: Re: Depth of field at infinity Stanley Halpin wrote: > You will get more diffraction at f/22 on a wide angle lens than you will at > f/22 on a mid-range lens than you will get at f/22 on a longer focal length. That's not true. Although the physical diameter of the aperture at any given f-stop is greater on longer focal lengths, the increase in magnification is *exactly* proportional, thus magnifying the diffraction effects of f/22 on a 300mm lens so they're exactly equal to the diffraction effects on a 24mm lens, for example. Ansel Adams and his f64 group actually made photos that lost quite a bit of sharpness due to diffraction. They made up for it by using large format view cameras that required little or no enlargement for printing. When I've looked genuine Ansel Adams prints close up aI've often been surprised at how sharp they aren't. -- Mark Roberts - Photography & Multimedia www.robertstech.com -- 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.
