Pentax users won’t be surprised to learn the smc DA* 300mm and 200mm lenses head this group. They are two very good performers with very low distortion, vignetting and well-controlled lateral chromatic aberration. Despite the longer focal length the 300mm has better uniformity that the 200mm and it’s sharper at maximum aperture (albeit a stop slower at f4 to start with). The 200mm really needs to be stopped down a stop, as sharpness at the initial aperture is a little disappointing. Center sharpness is good at f4 but optimum performance is not achieved till f5.6-8.
|Pentax smc DA Star 300mm F4 ED (IF) SDM||1400||17||9|
|Pentax smc DA Star 200mm F2.8 ED (IF) SDM||1200||17||8|
|Pentax smc PENTAX DA 55-300mm F4-5.8 ED||475||14||7|
|Pentax smc Pentax DA 18-250mm F3.5-6.3 ED AL [IF]||499||13||8|
|Sigma 18-200mm F3.5-6.3 II DC OS HSM Pentax||349||13||7|
|Pentax smc DA 18-270mm F3.5-6.3 ED SDM||749||13||7|
|Pentax smc PENTAX DA 50-200mm F4-5.6 ED||261||12||6|
|Tamron AF18-200mm F/3.5-6.3 XR Di-II LD ASPHERICAL (IF) MACRO Pentax||645||9||5|
In third place is the smc DA 55-300mm f4.5-5.8 ED, a modestly priced zoom the equivalent to an 85-460mm. It might lack the sonic-type motors of the 200mm and 300mm but what it lacks in features it more than makes up for in image quality. Unlike most lenses of this type, which are sharper at the shorter end of the zoom range, this lens performs best at 300mm. And, it has very good sharpness wide-open. Admittedly that’s a slow f5.8 at 300mm and it’s not nearly so good at 200mm (unless stopped down to f8) either, but performance starts to pick up again at 100mm at wider apertures. It has a rather complex sharpness profile, however at $475 it offers far more flexibility and is a good choice where a long telephoto might only be used occasionally.
We’re working hard on expanding the coverage of Pentax lenses, but we’re interested to know if there are certain models that you would like to see reviewed first. Please leave your recommendations in the comments section below.