The Sigma 135-400 APO f4.5-5.6 is considered to be an excellent,sharp telephoto zoom lens. It is available in most popular mounts. There is an older version and the newer DG. DG incorporates a digital coating that might make it slightly better than the older non-DG version.
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| Sigma APO 135 400mm F 45 56 Telephoto Lens For Minolta Sony Alpha | |
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$349.95 Time Remaining: 19d 12h 51m Buy It Now for only: $349.95 Buy It Now | Add to watch list |
| Sigma 135 400mm APO DG Lens for Sigma Cameras 135 400 mm USA | |
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$399.00 Time Remaining: 15d 54m Buy It Now for only: $399.00 Buy It Now | Add to watch list |
Here is the FM review page for this lens.