Decent image quality
Low vignetting even on full frame
Fast and positive autofocus
Very good build quality, excellent tripod collar design
Low price
缺點:
Relatively weak at 200mm (softness, chromatic aberration, pincushion distortion on full frame)
Unconvincing 'macro' performance; soft at wider apertures, significant focus shift on stopping down
Red/cyan bokeh chromatic aberration
評價:
I am thinking of buying this one as this is cheaper then the Canon one (Sigma - around $6000 and around $9000 for Canon)
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