----- Original Message ----- From: "Sylwester Pietrzyk" Subject: Re: Sigma 300/2.8 DG for Pentax
> Of course. But then we should compare 400/5.6 on APS-C camera to > 600/5.6 on FF - which one would be smaller and lighter? ;-) Good question. Long lenses inherently have large image circles, so the amount of coverage becomes closer to being one of focal length rather than designed lens coverage. The 645A 600/5.6 weighs significantly more than the KA-600/5.6, and is somewhat smaller in one dimension, longer in another, but the 6x7 600/4 weighs less than the FA 600/4 and is smaller in both dimensions than it's 35mm sibling. I'm not sure if the final weight or size can be determined by format coverage alone. I am noticing though, that one size smaller coverage lenses in the shorter focal lengths aren't really that much smaller than similar focal lengths (the Sigma 12-24 being somewhat of an exception, especially the weight) than similar full coverage focal length lenses. William Robb -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net
