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Make
Canon
Model
Canon EOS 50D
ISO Speed
200
Focal Length
35.0mm
Aperture:
f/8.0
Exposure
1/200s
Make
Canon
Model
Canon EOS 50D
ISO Speed
200
Focal Length
39.0mm
Aperture:
f/8.0
Exposure
1/320s
Make
Canon
Model
Canon EOS 50D
ISO Speed
200
Focal Length
21.0mm
Aperture:
f/8.0
Exposure
1/640s
Make
Canon
Model
Canon EOS 50D
ISO Speed
200
Focal Length
30.0mm
Aperture:
f/8.0
Exposure
1/400s
Make
Canon
Model
Canon EOS 50D
ISO Speed
200
Focal Length
18.0mm
Aperture:
f/8.0
Exposure
1/800s
Make
Canon
Model
Canon EOS 50D
ISO Speed
200
Focal Length
55.0mm
Aperture:
f/5.6
Exposure
1/1000s
Make
Canon
Model
Canon EOS 50D
ISO Speed
200
Focal Length
55.0mm
Aperture:
f/5.6
Exposure
1/800s
Make
Canon
Model
Canon EOS 50D
ISO Speed
200
Focal Length
31.0mm
Aperture:
f/9.0
Exposure
1/500s
Make
Canon
Model
Canon EOS 50D
ISO Speed
200
Focal Length
55.0mm
Aperture:
f/9.0
Exposure
1/400s
Make
Canon
Model
Canon EOS 50D
ISO Speed
200
Focal Length
18.0mm
Aperture:
f/9.0
Exposure
1/640s
Make
Canon
Model
Canon EOS 50D
ISO Speed
200
Focal Length
24.0mm
Aperture:
f/9.0
Exposure
1/250s
Make
Canon
Model
Canon EOS 50D
ISO Speed
400
Focal Length
18.0mm
Aperture:
f/5.0
Exposure
1/160s
Verdict
Many users will probably think that OpticalLimits went gaga considering the resolution results of the Canon EF-S 18-55mm f/3.5-5.6 STM IS. Honestly, we'd prefer it to be worse so we wouldn't need to argue. :-) Anyway, keep in mind that this is a zoom lens with a very moderate 3x zoom ratio and a slow max. aperture range. Such lenses are relatively easy to design and the challenges are well understood- so this may partly explain the relatively high resolution results. So yes, this little fellow is a pretty darn sharp lens with only a minimal decrease in contrast fully open. However, it is not a lens without flaws. There is a bit of field curvature so expect a slight corner softness when shooting flat objects at max. aperture. The CAs are generally quite low but they are easily visible in the image corners at 18mm. The 18mm setting is also a weak spot both in terms of distortion and vignetting although this is actually nothing out of the ordinary for a lens in this class. So despite the excellent MTFs we were a little shy of giving it a straight 4* optical rating.
Canon improved the mechanical quality of the EF-S 18-55mm f/3.5-5.6 STM IS compared to its predecessors. It remains, of course, a "plastic" lens but we can celebrate the comeback of a dedicated focus ring and the implementation of a non-rotating front element as well as a generally higher build quality. The new STM AF is really silent and pretty speedy. Canon's IS (image stabilizer) is a proven technology by now and it's a welcome feature to help out in low light situations. Most users will probably purchase the lens as part of a camera kit at little extra costs. It's not a pricey item when buying it separately and you may notice that there is a bit of price hike compared to its predecessors. That said, it's still a bargain for what it does!
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