Originally posted by mekiAus From the forum database 2 Pentax lenses seemed to meet my criteria: the FA* 24mm f/2 AL IF and the A 24mm f/2.8. I have not yet checked non-pentax alternatives.
Have I already responded to one of your posts? These are my two favorites. I really liked the A24, but the FA*24 is a huge advantage to me now because of the AF, which I often rely on. The f/2 comes in more handy than you might think - very good IQ at f/2.2 is a real strength of this lens, and it makes it more versatile. This is what I'm sure I'd pick for most street photography, unless you want to get a dedicated camera with the same focal length (like one of Fuji X100 series cameras (there are three models now!)).
Originally posted by mekiAus 2. 200mm Prime (for k-3) for moderate distance nature, inside sports and head shots in moderate / poor light. Here I located 4 candidate Pentax lenses: Two k-mount lenses, the 200mm f/2.5 and the 200mm f/4; the A* 200mm f/2.8 ED and the A 200mm f/4. I must admit that the A* looks fantastic, but it is probably out of my price range.
Again, I would imagine you want AF sometimes. In this case the DA*200 is out, because the AF is too slow for some sports. True, it works in some circumstances, but it's the slowest focusing lens I've ever tried for sports. I kept it less than 2 weeks before re-selling it. IQ was still very good. Therefore get the FA*200/2.8 instead - same optical formula and faster focusing on your K-3. One forum member claimed the DA*200 focuses quickly on the K-3, but this would be virtually impossible unless there's a firmware fix I'm unaware of. Until I get more evidence I'll assume it's still slow-focusing on any body.
If you don't need AF the K200/2.5 (which I have) is very nice.
There's a pretty good chance you need to stop down the Sigma 120-400 a bit to get the IQ you want. Therefore a *300 (DA/FA/F) may still be a big upgrade. They're very good wide open, and especially strong when stopped down only 1/3 stop. Combined with their excellent overall IQ they make more difference than you might expect. I don't know if you're really sure you want the 200mm focal length (I find I can usually take only the F*300 and leave the K200/2.5 home, especially since it's not AF) or just the f/2.8 aperture. If you're not sure I'd lean toward a *300, since they have a little better IQ than the DA/FA*200, and 300mm often turns out to be a good or better FL anyway. Nevertheless, the FA*200 is still very nice.
Last edited by DSims; 02-03-2015 at 12:15 AM.