There is ZERO advantage to using macro lenses at subject distances covered by normal lenses. Actully there is usually a disadvantage, so using a macro lens for non macro work makes no sense and my comments were certainly not for that case! JCO
-----Original Message----- From: Tom Reese [mailto:[EMAIL PROTECTED] Sent: Saturday, November 13, 2004 12:00 PM To: [EMAIL PROTECTED] Subject: RE: A Question About Macro Lenses "J. C. O'Connell" objected to my opinion and responded: "I don't agree (1): The major differences between macro lenses and non-macro lenses is that macro lenses have special optical designs which optimize near field usage in the range of 1:1 to 1:10 (approx). They have different OPTICAL designs. It is not just a matter of close focus capability, that can be achieved by putting non-macro lenses on tubes or bellows but they will not perform nearly as well a true macro lenses because just increasing close focus ability without the optical redesign yields mediocre results....." I am well aware that the optical designs are very different but in real world actual usage, the major difference is that the macro lenses focus closer. At f/8 or f/11 both lenses are at optimal resolution and I don't think you'll see an appreciable difference in image quality when both lenses can focus on the subject. If the 105mm lens required an extension tube to focus on the subject then the macro lens would probably outperform it. Refer to the original question. The images were shot at a distance where both lenses were able to focus on the subject. At that distance, the macro lens did not yield a substantially better image than the 105. I am not at all surprised that it did not. Tom Reese
