12-15-2010, 10:15 PM
[quote name='Grummbeerbauer' timestamp='1292448016' post='5021']
I have to say that I fully agree with your assessment, Rainer (I actually just registered at the PZ forum to get this off my chest).
When comparing the measurements (whether it is sharpness, vignetting, CA) at comparable apertures, the differences between the Zeiss and the Canon are minimal if non-existent. So I do not fully understand why the Canon gets only three stars for optical quality, while the Zeiss gets 3.5 to 4 stars here. Of course the Canon is more expensive, larger and (surprisingly not that much) heavier, but this should not be reflected in the optical quality rating. Klaus mentions that the Zeiss has very good bokeh, while he critizes the Canon's bokeh. Maybe this contributes to the different rating. Unfortunately, I can't seem to find a bokeh shot for the Zeiss to judge on my own.
The question is whether two lenses that perform the same in the range of their spec where they overlap (e.g., the aperture ranges per FL covered by both, the shared FL range, etc.), but one of the two offers a large range for one or more of these specs (like in this case, a larger maximum aperture or a larger zoom range... you get the point) should get the same optical quality rating, even if the "extra" offered by one lens is significantly worse than the comparable common spec range. In other words: should a f1.4 lens be penalized for not being that great at f1.4, even if its performance is virtually identitical to that of the other lens at f2 and smaller. I think it should be reflected in some way, but how?
[/quote]
So how do you rate the performance at f/1.4 then ? This cannot be ignored. If it offers f/1.4 (and priced higher) it should deliver something more than that. Just arguing that the marks aren't much worse at comparable apertures doesn't seem to be valid to me.
I have to say that I fully agree with your assessment, Rainer (I actually just registered at the PZ forum to get this off my chest).
When comparing the measurements (whether it is sharpness, vignetting, CA) at comparable apertures, the differences between the Zeiss and the Canon are minimal if non-existent. So I do not fully understand why the Canon gets only three stars for optical quality, while the Zeiss gets 3.5 to 4 stars here. Of course the Canon is more expensive, larger and (surprisingly not that much) heavier, but this should not be reflected in the optical quality rating. Klaus mentions that the Zeiss has very good bokeh, while he critizes the Canon's bokeh. Maybe this contributes to the different rating. Unfortunately, I can't seem to find a bokeh shot for the Zeiss to judge on my own.
The question is whether two lenses that perform the same in the range of their spec where they overlap (e.g., the aperture ranges per FL covered by both, the shared FL range, etc.), but one of the two offers a large range for one or more of these specs (like in this case, a larger maximum aperture or a larger zoom range... you get the point) should get the same optical quality rating, even if the "extra" offered by one lens is significantly worse than the comparable common spec range. In other words: should a f1.4 lens be penalized for not being that great at f1.4, even if its performance is virtually identitical to that of the other lens at f2 and smaller. I think it should be reflected in some way, but how?
[/quote]
So how do you rate the performance at f/1.4 then ? This cannot be ignored. If it offers f/1.4 (and priced higher) it should deliver something more than that. Just arguing that the marks aren't much worse at comparable apertures doesn't seem to be valid to me.