On Fri, 11 Jan 2002 11:15:16 +1300, you wrote: >Fred wrote: > >> And, the 300/4 >> must be infinitely better at f/4 than the 300/4.5 would be at f/4, >> right? <g> > > And the 300/4 stopped down to f/4.5 might be sharper than the 300/4.5 wide >open...
The F* 300/4.5 is as sharp or sharper at f4.5 than the M* 300/4 is at f5.6. And the difference between the two lenses is 1/3 stop, not 1/2 stop (but the difference between 1/3 and 1/2 is only 1/6, so there's really not much difference between 1/3 and 1/2, and... oh, what was I talking about?) Anyway, as one who has owned and enjoyed both of these fine lenses, I much prefer the F* 300/4.5 for optical quality, ease of use, and slightly smaller size, especially when I replace its huge tripod foot with the one from the A* 200/4 Macro. With a 25mm AF extension tube, the F* 300/4.5 also produces excellent close-ups. My only real complaint about the M* 300 I owned was the focus speed - I just never learned to twist that stiff focus ring fast enough - and its wide open performance. For the same money as the M* or A* 300/4, I prefer the K-series 200/2.5, which is very similar in size and handling as those 300mm manual focus lenses. Adding the Pentax 1.7X AF Adapter to the 200/2.5 gives me a semi-AF lens of 340/f4.5, which along with its native 200/2.5 length makes this a hard combo to beat for an all-in-one traveling long lens. -- John Mustarde www.photolin.com - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
