I bought my first FA Power Zoom 28-105 f4-5.6 (produced 1992-1999, according to Boz's site) in spring 1999. The lens manual mentions the 43 Limited (introduced 1997) but not the FA 20-35 (introduced 1998). Not knowing how promptly Pentax updates the lens manuals, I can guess that perhaps this lens was manufactured in 1997 or 1998. Since Pentax, like any manufacturer, will sometimes design a product then decide not to market it, one would not want to revise the lens manual until a new lens (the 20-35 in this case) is in production.
The FA* 24 f2.0 (introduced 1991) that I just got came with a more outdated manual. It mentions some F zooms that have been replaced by FA versions (35-80, 80-200). It mentions the F 17-28 fisheye (introduced 1995), but as far as I can tell, nothing introduced since then. This leads me to speculate on production, as follows: Zoom lenses that sell well are produced continuously. Specialty primes, on the other hand, might be produced in batches, then not produced for a while until the stock runs down. I don't know much (okay, anything) about manufacturing, but I would guess that it is costly to start a production run. A manufacturer would not want constantly to stop and re-start production of a specialty lens. Is it more economical just to produce a bunch of them at a time, then store the stock? According to Boz's site, the FA* 24 is still in production. Does this mean that it is actually being produced, or that Pentax would be willing to re-start production if demand warranted it? Just speculating. Quality note: The lens hood that comes with the FA* 24 is lined with black felt. Nice touch. And the canals for attaching the hood seem designed for more durability than one usually sees. To me, attention to detail in small things like these is impressive. Joe
