1500mm lens FOV though. 3000mm final. imagine carrying that one around. Herb... ----- Original Message ----- From: "Boris Liberman" <[EMAIL PROTECTED]> To: "Herb Chong" <[EMAIL PROTECTED]> Sent: Sunday, March 14, 2004 2:21 PM Subject: Re: PAW: sparrows
> Hi! > > I am half mathematician by education. So here is my math: > > Sigma 50-500 at 500 mm plus Sigma 2x extender = 1000 mm. Crop of 50% > center portion means like 2x more = 2000 mm. Roughly 1.5 *istD factor > = 3000 mm > > HC> taken on the *istD with a Sigma 50-500 and Sigma 2X extender at 500mm wide > HC> open and then cropped to the 50% center portion. equivalent FOV to a 1500mm > HC> lens on a 35mm film body. > > Right?
