Originally posted by ogl Can you explain how DA Limiteds replace FA Limiteds?
Thank you for asking. Yes I can explain it.
You see, the DA Limiteds are for APS-C. Pentax has stopped making 24x36 bodies. Pentax concentrates on APS-C. Pentax has discontinued most of their 24x36 lenses. The only ones that they keep is those that has proven to still be popular, but those few remaining 24x36 lenses lives on borrowed time.
The DA serie has replaced the FA serie. The DA Stars replaced the FA Stars. The DA Limiteds replaced the FA Limiteds.
Quote: It's absolutely differents lines of lenses - DA LIMITEDs are more compact and APS-C design, slower than FA LIMITED.
That is true. The DA's are a different lines of lenses than the FA lenses, being more compact and more APS-C and fewer lenses with wide aperture - still the DA replaced the FA. Replacements does not automatically mean identical.
The K-7 replaced the K20D. More compact, having higher price. A new design. Different kind of camera than the K20D. Still it was a replacement.
Quote: Which DA lens replaced FA31/1.8 (the one of the best wide-angle lens in the world)? Do you really think that it's DA21???
Just as the DA lens line replaced the FA lens line without having equivalents to all FA lenses, the DA Limiteds replaced the FA Limiteds. But with one difference, FA Limiteds kept in production for longer - because there was a demand for them.
Quote: If we talk about ~90-95% (35 mm equivalent focal range and DOF) replacement of FA LIMITED by APS-C lenses
So? The DA Stars should have wider apertures than the FA Stars they replaced in order to keep the same DOF, still they are not faster than f/2.8 so they actually has different DOF's than the FA Stars. Still, they replaced the FA Stars without being identical.
DA 17-70 f/4 replaced the FA 28-105 f/3.2-4.5. But the 17-70 has slower aperture at the wide end.
DA 16-45 f/4 replaced both the FA 28-70 f/4 and FA 24-90 f/3.5-4.5, but they are not identical in focal lengths even when taking into account the 1.5x factor.
And so on. It seems possible for Pentax to replace a lens line with lenses that aren't identical to the lenses that are being replaced. Just as they do with bodies.
Because the FA lenses were designed for 24x36 and Pentax does not offer 24x36 bodies. They offer APS-C bodies and their goal is to make lenses that fits APS-C well, that meets the demand of good build quality with useful focal lengths, being compact and still fast enough. Those requirements means different thinking than the previous thinking that designed the FA serie. The DA 40 has become a success. So Pentax designs more lenses with compact dimensions, exclusive build quality and nice retro touches for APS-C. It is the APS-C equivalent to the FA Limiteds for 24x36.