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Am I hearing things? Today I recv'd this Sigma 120-400mm 1:4.5-5.6 APO DG OS HSM lens with a Nikon mount. When in AF mode I can hear what I think are gears
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Sigma / Carl Zeiss Jena (AF and MF) IF MC multic 400mm F5.6 Lens Reviews - Sigma Lenses - Pentax Lens Review Database
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Sigma 100-400 "Real World Review": The BEST "Affordable" Wildlife / Sports lens for under $700 - YouTube
SIGMA 100-400mm f/5.0-6.3: Nikon DX SLR (D40-D90, D3000-D7500) Talk Forum: Digital Photography Review
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