[quote name='Studor13' timestamp='1320739945' post='12747']
What does this tell you?[/quote]
Among other things, that owners and users tend to justify their purchases. The worse the score here, the more they do. Happened with the AF-D 85/1.4 before (and quite a few others), but that doesn't change any of the scores we measured here.
What does it tell you that there are quite a few responses in threads over at dpr and elsewhere that confirm our findings?
[quote name='Studor13' timestamp='1320739945' post='12747']
I have not read onereport other than PZ giving the 18-35 such a bad review.
[/quote]
Right. And especially no other review where the lens was tested on either the D7000 or the D3x. Most of the other reviews you mention tested the lens on less demanding sensors. Including all of the reviews and reviewers you mentioned. Like Ken, where...
[quote name='Studor13' timestamp='1320739945' post='12747']
it was tested on a d3!
[/quote]
...which has even lower pixel density than a D70. Or D100.
[quote name='Studor13' timestamp='1320739945' post='12747']
Correct me if I am wrong, but someone mentioned to me that PZ's resolution testing is based on minimum or near-minimum distances. If this is the case, any conclusions are meaningless.[/quote]
No, the tests are done at 60x (DX) or 40x (FX) the focal length. This is far from minimum distance. In fact it's closer to infinity than MFD on the lens' distance scale.
But it has become a favourite argument of some who try to impeach our credibility. And usually is never an issue with reviews, where lenses score better than the AF-D 18-35.
[quote name='Studor13' timestamp='1320739945' post='12747']
Testing and concluding using one and only one sample does not lead to facts.
[/quote]
Of course it does. Facts based on one sample, but still facts. You may have well reasoned doubts that this single unit was not representative, but the only valid approach to prove our measurements wrong is to measure a second unit. Which, by the way, we very often do if we have doubts about the results we measure. And very often this is NOT mentioned in the review. Examples: I just finished measurements with a second unit of the AF-S 35/1.4 on the D7000. The upcoming review of the AF-S 105 VR on FX and DX is based on several units. Same applies to reviews of the Sigma 85/1.4, Nikon AF-D 85/1.4 and AF-S 85/1.4. The ZF 25 reviews are based on two units, just as most of the Voigtländer SL II reviews. Measurements of the Nikon AF-S 16-85 VR, Tamron 17-50 and 17-50 VC have been confirmed with additional samples after the reviews had been published. Next week, I'll get a second copy of the AF-S 24-70 to confirm my initial measurements on the D7000 (and I expect some improvement on FX here).
In case of the AF-D 18-35, however, a second unit has simply not been offered to us. And sorry, I'm not going to purchase one just for this purpose.
[quote name='Studor13' timestamp='1320739945' post='12747']
Look, I would like, and I'm sure we would all like PZ to be a reliable site for information on photographic equipment, in particular, lenses![/quote]
Sure. That's why I continue to ask for another loaner.
[quote name='Studor13' timestamp='1320739945' post='12747']
Granted, you have some problems with getting various samples.[/quote]
Usually not. Just in this case. For whatever reason.
[quote name='Studor13' timestamp='1320739945' post='12747']
However, I would like to contribute to PZ by lending some others that I do not use so frequently. For example, my trusty 75-150mm Series E, the outstanding 50-135mm f/3.5 and a few others.[/quote]
Thanks for your offer. However, the main focus is on current lenses for now and we unfortunately have only very limited resources to test discontinued lenses.
[quote name='Studor13' timestamp='1320739945' post='12747']
And finally, some photos with the 18-35. It's not about resolutions. It's all about the light!
[/quote]
Of course. And/or the subject. But not for (objective) reviews. The samples you posted, especially downscaled that much, tell us a lot about your skills as a photographer, but close to nothing about the optical quality of the lens used <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/wink.gif' class='bbc_emoticon' alt='
' />
-- Markus
What does this tell you?[/quote]
Among other things, that owners and users tend to justify their purchases. The worse the score here, the more they do. Happened with the AF-D 85/1.4 before (and quite a few others), but that doesn't change any of the scores we measured here.
What does it tell you that there are quite a few responses in threads over at dpr and elsewhere that confirm our findings?
[quote name='Studor13' timestamp='1320739945' post='12747']
I have not read onereport other than PZ giving the 18-35 such a bad review.
[/quote]
Right. And especially no other review where the lens was tested on either the D7000 or the D3x. Most of the other reviews you mention tested the lens on less demanding sensors. Including all of the reviews and reviewers you mentioned. Like Ken, where...
[quote name='Studor13' timestamp='1320739945' post='12747']
it was tested on a d3!
[/quote]
...which has even lower pixel density than a D70. Or D100.
[quote name='Studor13' timestamp='1320739945' post='12747']
Correct me if I am wrong, but someone mentioned to me that PZ's resolution testing is based on minimum or near-minimum distances. If this is the case, any conclusions are meaningless.[/quote]
No, the tests are done at 60x (DX) or 40x (FX) the focal length. This is far from minimum distance. In fact it's closer to infinity than MFD on the lens' distance scale.
But it has become a favourite argument of some who try to impeach our credibility. And usually is never an issue with reviews, where lenses score better than the AF-D 18-35.
[quote name='Studor13' timestamp='1320739945' post='12747']
Testing and concluding using one and only one sample does not lead to facts.
[/quote]
Of course it does. Facts based on one sample, but still facts. You may have well reasoned doubts that this single unit was not representative, but the only valid approach to prove our measurements wrong is to measure a second unit. Which, by the way, we very often do if we have doubts about the results we measure. And very often this is NOT mentioned in the review. Examples: I just finished measurements with a second unit of the AF-S 35/1.4 on the D7000. The upcoming review of the AF-S 105 VR on FX and DX is based on several units. Same applies to reviews of the Sigma 85/1.4, Nikon AF-D 85/1.4 and AF-S 85/1.4. The ZF 25 reviews are based on two units, just as most of the Voigtländer SL II reviews. Measurements of the Nikon AF-S 16-85 VR, Tamron 17-50 and 17-50 VC have been confirmed with additional samples after the reviews had been published. Next week, I'll get a second copy of the AF-S 24-70 to confirm my initial measurements on the D7000 (and I expect some improvement on FX here).
In case of the AF-D 18-35, however, a second unit has simply not been offered to us. And sorry, I'm not going to purchase one just for this purpose.
[quote name='Studor13' timestamp='1320739945' post='12747']
Look, I would like, and I'm sure we would all like PZ to be a reliable site for information on photographic equipment, in particular, lenses![/quote]
Sure. That's why I continue to ask for another loaner.
[quote name='Studor13' timestamp='1320739945' post='12747']
Granted, you have some problems with getting various samples.[/quote]
Usually not. Just in this case. For whatever reason.
[quote name='Studor13' timestamp='1320739945' post='12747']
However, I would like to contribute to PZ by lending some others that I do not use so frequently. For example, my trusty 75-150mm Series E, the outstanding 50-135mm f/3.5 and a few others.[/quote]
Thanks for your offer. However, the main focus is on current lenses for now and we unfortunately have only very limited resources to test discontinued lenses.
[quote name='Studor13' timestamp='1320739945' post='12747']
And finally, some photos with the 18-35. It's not about resolutions. It's all about the light!
[/quote]
Of course. And/or the subject. But not for (objective) reviews. The samples you posted, especially downscaled that much, tell us a lot about your skills as a photographer, but close to nothing about the optical quality of the lens used <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/wink.gif' class='bbc_emoticon' alt='
' />-- Markus
Editor
opticallimits.com
opticallimits.com