03-31-2014, 11:11 AM
Hi all, just read the Zeiss review and it's not a stellar performer at all.
I miss only one point: it's nice to test a lens with 36MP A7R, but what about the focus shifts ? The A7R has contrast-type AF so via AF you can't see the focus shift as contrast type AF focuses just like LiveView: aperture already on it's final value - so focus will be much more exact than with phase-type AF-s.
Of course with MF, focusing on the ruler to the zero point and then aperture down, any kind of focus shift could be still measured but i'm just missing this part of the test really.
Because nowadays I see more and more very nice constructed lenses coming out - with focus shifts. Which is rather an "issue" coming from the optical formulas and construction, not a focus issue at the body, nor at the lens. But it affects focus, pretty much.
On my D800 I have a pretty decent Tamron 24-70 2.8 VC USD. With it's huge focus shift from f/2.8 to f/4. As I was looking at another "perfect" fullframe standard zooms, none of them are perfect, actually: Nikkor 24-70 is expensive and no OS, Sigma 24-105 no-go either, Nikkor 24-120 f4 same no-go (just too soft for a D800) and same applies for the Canons (24-70 expensive and no IS, 24-105 too soft). So, the only option would be to use contrast-based focus (liveview) on DSLR-s - then the Tamron could be one of the winners I think, but what else ?
In real life when I go from 2.8 to 4, my Tamron needs a new AF fine tune value, I have to change it to a different value. Insane. I use it at f/4 and beyond with 1 value, constantly. Due to increased DOF, that's good for everything already.
Sony A7R, due to it's contrast based focus, is a totally different story. My Tamron would be just perfect on the Sony, either as a native Sony mount, or with the Nikon adapter.
But this Zeiss is just .. big surprise.
Big name, big issues.
I miss only one point: it's nice to test a lens with 36MP A7R, but what about the focus shifts ? The A7R has contrast-type AF so via AF you can't see the focus shift as contrast type AF focuses just like LiveView: aperture already on it's final value - so focus will be much more exact than with phase-type AF-s.
Of course with MF, focusing on the ruler to the zero point and then aperture down, any kind of focus shift could be still measured but i'm just missing this part of the test really.
Because nowadays I see more and more very nice constructed lenses coming out - with focus shifts. Which is rather an "issue" coming from the optical formulas and construction, not a focus issue at the body, nor at the lens. But it affects focus, pretty much.
On my D800 I have a pretty decent Tamron 24-70 2.8 VC USD. With it's huge focus shift from f/2.8 to f/4. As I was looking at another "perfect" fullframe standard zooms, none of them are perfect, actually: Nikkor 24-70 is expensive and no OS, Sigma 24-105 no-go either, Nikkor 24-120 f4 same no-go (just too soft for a D800) and same applies for the Canons (24-70 expensive and no IS, 24-105 too soft). So, the only option would be to use contrast-based focus (liveview) on DSLR-s - then the Tamron could be one of the winners I think, but what else ?
In real life when I go from 2.8 to 4, my Tamron needs a new AF fine tune value, I have to change it to a different value. Insane. I use it at f/4 and beyond with 1 value, constantly. Due to increased DOF, that's good for everything already.
Sony A7R, due to it's contrast based focus, is a totally different story. My Tamron would be just perfect on the Sony, either as a native Sony mount, or with the Nikon adapter.
But this Zeiss is just .. big surprise.
Big name, big issues.