Much more light
As expected, all these improvements help the lens collect much more light. The T-stop results are far better for this new version. From 24 to 85mm, the results are good (f/4.3); from 85 to 120mm, the T-stop climbs to f/4.3 to f/4.6 on a D3x. This is far better than for the old zoom on the same camera, which was in any event limited by its smaller aperture at longer focal lengths.
24-120mm f/4 (orange) vs 24-120mm f/3.5-5.6 on an APS-C sensor (D300s)
Further readings for the DxOMark review for the Nikon 24-120, the new constant f/4 aperture on DxOMark.
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