Originally posted by bossa Hi Jay, but that lens is a DX format and whilst optically the same as the DA it doesn't have the coatings and WR.. I don't know how it would go in 1.2x mode but at 1x I doubt it would cut it.
I know, but you were comparing the K5 + 50-135 to the D800 + 70-200 in size, and the truth is the D800 in DX mode with the Sigma 50-150 would pretty much exactly match the K-5 + 50-135 in resolution and IQ, focus faster and come a lot closer to the Pentax combo in size. It's kinda academic since you don't have the Sigma, though, I was just saying that with a size-only comparison you can bring in DX mode and choose a DX lens if you want, since you have so many MP to work with.
This is the D800 + 50-150 in DX mode (15.5 MP)
150mm @ f/2.8 ISO 1600
75mm @ f/2.8
It doesn't have WR and is not stabilized, but there's nothing wrong with the coatings Sigma uses on it's EX line - lots of contrast and good flare control. What I really like that combo for though is the smaller size of the zoom compared to a 70-200 and the speed of that HSM on that body.
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