I think that there are a couple of "rules" that you can follow when discerning Good Zoom Lens designs from the pedestrian (even BEFORE looking at the pictures they produce).
1) In general, shorter focal length spreads will out-perform longer focal length spreads. Longer focal length spreads (extreme example: 28-200mm) may be convenient, since you don't have to change lenses often or carry extra lenses, but they aren't going to outperform the zooms 28-70mm and a 70-210mm (at any focal length) 2) A constant aperture zoom (if available) will generally out-perform a variable focal length zoom of the same focal length range. Example: Pentax-A 35-70mm f3.5-4.5 (variable aperture, filter size 49mm) is considered a decent lens, but the Pentax-A 35-70mm f4 (constant aperture, made for only two years, filter size 58mm) is considered a much better performer. The Pentax-A 35-105mm f3.5 is a bit of a longer focal length lens, but is a constant aperture and it is also highly regarded. (From PF reviews) A35-70mm f3.5-4.5; A35-70mm f4; A35-105mm f3.5 Sharpness: 8.3; 8.7; 9.1 Aberrations: 7.7; 8.8; 8.4 Bokeh: 7.0; 8.5; 8.3 On Wed, Sep 11, 2013 at 7:39 PM, Mark C <[email protected]> wrote: > Yes - that is what I meant - A 28-135 f4. Nice lens. > > > On 9/10/2013 1:30 PM, John wrote: >> >> Did you mean an A 28-135/4? I couldn't find an A 28-100/4. >> >> http://www.bdimitrov.de/kmp/lenses/zooms/short/A28-135f4.html >> >> On 9/9/2013 8:29 PM, Mark C wrote: >>> >>> Thanks - I remember you posting about this lens but had forgotten about >>> it. I had an A 28-100 f4 and loved it. I will keep my eyes peeled for >>> one of these. >>> >>> Mark >>> >>> On 9/9/2013 5:06 PM, Zos Xavius wrote: >>>> >>>> A35-105/3.5. I haven't taken it off my camera at all lately. Razor >>>> sharp at even f3.5. Stop down and it gets so sharp it will cut you. I >>>> like this lens so much I'm going to track down a minty copy soon. Mine >>>> has some slop in the focusing, but I've been more than ok with >>>> fighting the focus when I get the results back on my computer. You >>>> lose AF and 28mm at the wide end, so this might not work all that well >>>> for you. As much as I love wide angle, I'm finding the 35-100 range >>>> quite useful indeed. 50mm equivalent is a bit for a walk around >>>> though.....just a thought. >>>> >>>> >>> >>> >> > > > -- > PDML Pentax-Discuss Mail List > [email protected] > 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 [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
