03-10-2011, 12:36 AM
[quote name='clkirksey' timestamp='1299682020' post='6636']
I am trying to reconcile the differences in MTF50 values between PZ and dpreview.com site say for the Canon 70-200mm f/2.8L IS II on an APS-C format body. To what extent does the PZ results reflect postprocessing sharpening via Imatest?
[/quote]
I wouldn't go to do a cross-site comparison of reviews. They probably don't even use the same RAW converters, sharpening aside. Take a look at the effects of different RAW converters below:
http://www.rawtherapee.com/RAW_Compare/
Also, a lot of lens review sites are very cryptic about their methods (for example, some places say they address field curvatures and focus shifts but they never really explain how their test methodology achieves this). Dpreview is known for having good database of technical specs but they never really figured out how to do technical experiments... which is not a serious problem for them because their audience is mainly composed of soccermoms and soccerdads looking for a final rating such as "highly recommended", "recommended", etc. without wanting to understand the different facets of these complex things.
Personally speaking, I only look at the center performance when I'm looking at MTF results, unless they show the actual images and show the coming-in to and going-out of focus, so I can judge for myself.
GTW
I am trying to reconcile the differences in MTF50 values between PZ and dpreview.com site say for the Canon 70-200mm f/2.8L IS II on an APS-C format body. To what extent does the PZ results reflect postprocessing sharpening via Imatest?
[/quote]
I wouldn't go to do a cross-site comparison of reviews. They probably don't even use the same RAW converters, sharpening aside. Take a look at the effects of different RAW converters below:
http://www.rawtherapee.com/RAW_Compare/
Also, a lot of lens review sites are very cryptic about their methods (for example, some places say they address field curvatures and focus shifts but they never really explain how their test methodology achieves this). Dpreview is known for having good database of technical specs but they never really figured out how to do technical experiments... which is not a serious problem for them because their audience is mainly composed of soccermoms and soccerdads looking for a final rating such as "highly recommended", "recommended", etc. without wanting to understand the different facets of these complex things.
Personally speaking, I only look at the center performance when I'm looking at MTF results, unless they show the actual images and show the coming-in to and going-out of focus, so I can judge for myself.
GTW