The M* and A* 300mm f4 lenses were the smallest and lightest of their class and three of the front 4 elements in the front group are ED glass. It was, I believe, before Internal Focusing had come into use. In optical design, something has to give, and the Pentax optical designers decided (wisely I think) to sacrifice close focusing, probably thinking that someone who uses a 300mm lens is probably not buying it to focus on something 10 feet away. In any event, closer focus CAN be achieved, if one truly wants it, through extension tubes (though at the sacrifice of the infinity end of the scale). I believe those lenses were also sold before the age of "APO" lenses, though the M* and A* would probably be classed as near-APO.
On Fri, Oct 11, 2013 at 9:28 PM, Mark C <pdml-m...@charter.net> wrote: > I have the A* 300 f4 and have to say that while it can be very good, it > falls short of being a truly excellent lens. It also falls short in the > close focus department. (Or maybe that should be that it falls long in the > close focus department.) I use the 1.7x converter on an A*400 f2.8 and it > is a tremendous help, but the AF range is fairly limited, not like a true AF > lens, in my experience - it needs to be pre focused to a fairly narrow > tolerance. But, the AF adapter is still better than my eyesight for fast > focusing. > > Mark > > > On 10/11/2013 5:24 PM, Rob Studdert wrote: >> >> There's a big difference in optical capabilities between these three >> lenses, the 300/4 variants are positively soft compared to the >> A300/2.8, having owned and used both. I still have the A300/2.8 which >> although unwieldy is a great lens when you need the speed and reach >> and combined with the 1.7AF TC it becomes an excellent AF combo. >> >> On 12 October 2013 02:21, P.J. Alling <webstertwenty...@gmail.com> wrote: >>> >>> And for a little over 1/5th of that price have the A*300 4.0 or a little >>> over 1/6 the M* when they're available, and if you really want the feel >>> for >>> carrying around f2.8 long glass you can get the [K} 300mm f4.0, >>> (available >>> at KEH for less than 1/10 the price, which even though it's a big heavy >>> beast is still half the weight of the A* 2.8. Considering size weight >>> and >>> cost, which lens am I more likely to haul around with me... >>> >>> Bottom line you don't take many pictures with a lens you don't have with >>> you. >>> >>> >>> On 10/11/2013 8:47 AM, Darren Addy wrote: >>>> >>>> If I had the discretionary income I would discreetly purchase this bad >>>> baby: >>>> Pentax-A* 300mm f2.8 >>>> >>>> >>>> >>>> http://www.keh.com/camera/Pentax-Manual-Focus-Fixed-Focal-Length-Lenses/1/sku-PK060090145530?r=FE >>>> >>>> http://www.flickriver.com/lenses/pentax/smcpa300mmf28edif/ >>>> >>> >>> -- >>> A newspaper is a device for making the ignorant more ignorant, and the >>> crazy, crazier. >>> >>> - H.L.Mencken >>> >>> >>> >>> -- >>> PDML Pentax-Discuss Mail List >>> PDML@pdml.net >>> 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 > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and > follow the directions. -- Nothing is sure but death and Pentaxes. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
