Why do you have a different scale for almost all canon lenses that you test? Sometimes excelent starts at 2280, and sometimes it starts much lower. Are you using the same units everytime? Is it possible to use the same grading scale for all lenses? Also i noticed that sometimes your MTF values and those of dpreview.com dont match up, even for the same lens, is it because you test differently?
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04-19-2012, 08:19 AM
(This post was last modified: 04-19-2012, 08:20 AM by Klaus.)
[quote name='ryans' timestamp='1334771667' post='17576']
Why do you have a different scale for almost all canon lenses that you test? Sometimes excelent starts at 2280, and sometimes it starts much lower. Are you using the same units everytime? Is it possible to use the same grading scale for all lenses? Also i noticed that sometimes your MTF values and those of dpreview.com dont match up, even for the same lens, is it because you test differently?
[/quote]
There are 3 scales in the EOS sections:
Tests based on 8mp APS-C
Tests based on 15mp APS-C
Tests based on 21mp Full Format
The MTF analysis is performed on image files and the max. LW/PH depends on the underlying camera.
Maybe start at the overview levels - it's more obvious then:
[url="http://www.opticallimits.com/canon-eos"]http://www.opticallimits.com/canon-eos[/url]
[url="http://www.opticallimits.com/Reviews/canon-eos-full"]http://www.opticallimits.com/Reviews/canon-eos-full[/url]
I reckon you came in via a search engine ?
Yes, I came in from a search engine at first, but have really grown to enjoy your site and the great job you do in testing lenses.
I now understand that the LW/PH is based on the camera/sensor used behind the lens, thanks for clearing that up.
It would be interesting if you could use the same lens on different cameras, and compare the MTF of the cameras themselves. Like using a Nikon lens with an adapter on a Canon body and compare maybe the D5100 to the 600D? I don't know if that would produce any sort of useful information.
Anyways, keep up the good work and thanks for the quick response!
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[quote name='ryans' timestamp='1334848503' post='17608']
Yes, I came in from a search engine at first, but have really grown to enjoy your site and the great job you do in testing lenses.
I now understand that the LW/PH is based on the camera/sensor used behind the lens, thanks for clearing that up.
It would be interesting if you could use the same lens on different cameras, and compare the MTF of the cameras themselves. Like using a Nikon lens with an adapter on a Canon body and compare maybe the D5100 to the 600D? I don't know if that would produce any sort of useful information.
Anyways, keep up the good work and thanks for the quick response!
[/quote]
Well, there are multiple third party lenses that have been tested on various DSLRs.
