02-20-2012, 08:05 AM
(This post was last modified: 02-20-2012, 08:06 AM by Brightcolours.)
The 14-24mm f2.8 is not a good example. There is clearly going on more than just a higher pixel pitch between reviews. The difference in edge/corner resolution can only be explained by not too accurate testing procedures and/or probably two different lens samples.
Of course, one will expect lower values in areas where the lens was not stellar with the lower resolution camera in the first place, but not a difference like this.
You only have to take another lens as example to see that there is more going on with the two 14-24mm f2.8 tests than different res. sensors. Take for instance the Tamron 17-50mm f2.8 (non-VC).
Its performance wide open at for instance 17mm is comparable to the performance of the 14-24mm wide open at 14mm, both on D7000. But... different story on D200. There, the 14-24mm f2.8 tested there performs way better. The Tamron performs as one would expect.
It is safe to conclude then that what we see with the 14-24mm f2.8 reviews, there is something else in play. Youpii's remark is not too far from "reality"... only when you already get very bad results on the lower res. sensor, you do not get kind of similar results on a higher res. sensor. Most lenses with perform well on the 24mm D3X will perform very well (and deliver extra resolution in images) on a D800.
We can observe another oddity too, but that in my opinion almost certainly has to do with the testing procedure. The "measured" CA is twice as high with the D7000 values than with the D200 values. But this matches the odd calculated values in other tests.. not a reliable method to determine CA amounts.
Of course, one will expect lower values in areas where the lens was not stellar with the lower resolution camera in the first place, but not a difference like this.
You only have to take another lens as example to see that there is more going on with the two 14-24mm f2.8 tests than different res. sensors. Take for instance the Tamron 17-50mm f2.8 (non-VC).
Its performance wide open at for instance 17mm is comparable to the performance of the 14-24mm wide open at 14mm, both on D7000. But... different story on D200. There, the 14-24mm f2.8 tested there performs way better. The Tamron performs as one would expect.
It is safe to conclude then that what we see with the 14-24mm f2.8 reviews, there is something else in play. Youpii's remark is not too far from "reality"... only when you already get very bad results on the lower res. sensor, you do not get kind of similar results on a higher res. sensor. Most lenses with perform well on the 24mm D3X will perform very well (and deliver extra resolution in images) on a D800.
We can observe another oddity too, but that in my opinion almost certainly has to do with the testing procedure. The "measured" CA is twice as high with the D7000 values than with the D200 values. But this matches the odd calculated values in other tests.. not a reliable method to determine CA amounts.