Babaluh schrieb:
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Soviel zu meiner "Hilfestellung".
Hat sich der Aufwand für das Schreiben dieser Zeilen für Dich tatsächlich gelohnt? Nimm Dir ein Beispiel an Helmut.
@ all: Wer die offensichtlichen Schwächen des EF-S 17-85 IS USM im WW bestreitet und herunterspielt, der sollte sich einfach mal in einer ruhigen Minute und evtl. mit Hilfe eines dictionarys das Folgende lesen und verstehen:
Quelle: dpreview.com:
"Resolution: Best results are obtained in the normal to telephoto range, where the lens gives consistently high MTF readings from 35mm to 85mm. Unfortunately things go downhill towards wide angle, especially in the corners which are distinctly soft at 17mm. The lens appears to be optimized to perform wide open at all focal lengths, and shows no systematic increase in quality on stopping down to smaller apertures; at F11 and beyond the sharpness drops rapidly due to diffraction, as expected. We’d certainly advise against using apertures much smaller than F16, except in those rare cases where extreme depth of field is important.
Chromatic Aberration: Chromatic aberration is distinctly worst at 17mm, where the almost-overlapping red and blue lines indicate green-magenta fringing, which is visually the most intrusive (see also the example below). The story is similar at 24mm, but at 35mm and beyond CA becomes much less of an issue.
Falloff: We consider falloff to become perceptible when the corner illumination falls to more than 1 stop less than the centre. Once again, the lens gives a poor showing at 17mm, with 1.7 stops of falloff wide open; you’ll need to stop down to around F8-11 to reduce it completely below perceptible levels. However aside from that, there’s nothing too much to worry about, with just a hint of falloff wide open at 24mm.
Distortion: The 17-85mm also shows unusually high barrel distortion at wide angles, measuring a whopping 2.4% at 17mm. This is also not ‘pure’ barrel distortion but a more complex ‘wave’-type, with the barrel effect most pronounced towards the centre, then pinched in again towards the edges, which makes it relatively difficult to correct in software. At 24mm and longer the pattern changes to pincushion, and at its worst reaches -1.5% at 50mm; again pretty pronounced, and readily visible if the image should contain straight lines."
In ähnlicher Dramaturgie ist dies auch im Test auf photozone.de und etwas abgeschwächter auf the-digital-picture.com nachzulesen. Hätte Canon tatsächlich dieses Objektiv überarbeitet, dann würde es sicherlich im Namen eine römische Zwei tragen. Daher gehe ich davon aus, dass es bei diesem Objektiv wohl eine recht ausgeprägte Serienstreuung gibt.
So, ich habe meine Informationen. Der Thread kann geschlossen werden.
