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Canon EF 11-24mm f/4 USM L
#13
Judging from the 70-200, I don't think a "good copy" of the 11-24 exists.  They must all be wrong at one end or the other.

 

Canon's MTF shows a strong astigmatism, so by playing with the focus you should be able to fix the bad corners at 11mm.  In real life images anyway - that'd be fudging it for a resolution test. 

 

Regarding MTF; many lenses improve considerably when you add the coverglass of the sensor to the path.  If a lens has undercorrected spherical aberration there is a solid chance it will improve. (And almost all do).

 

The actual sensor itself tends to have shit MTF towards the edges.  This is a big issue with digital and requries a telecentric lens design to solve, which the 11-24 is decidedly not.  True cine lenses do better in that respect.

 

Here's the mesaured MTF of the 135L.  Agrees quite closely with canon's published chart.

 

https://www.dropbox.com/s/4kgroq1gz3b0lq..._.png?dl=0

 

Most lens models are assembled too imperfectly on average to resemble the mfg published charts, but it is possible some copies do resemble them.

  


Messages In This Thread
Canon EF 11-24mm f/4 USM L - by Klaus - 07-12-2015, 07:30 AM
Canon EF 11-24mm f/4 USM L - by davidmanze - 07-12-2015, 08:34 AM
Canon EF 11-24mm f/4 USM L - by Klaus - 07-12-2015, 08:36 AM
Canon EF 11-24mm f/4 USM L - by Klaus - 07-12-2015, 08:41 AM
Canon EF 11-24mm f/4 USM L - by soLong - 07-12-2015, 08:46 AM
Canon EF 11-24mm f/4 USM L - by Klaus - 07-12-2015, 09:02 AM
Canon EF 11-24mm f/4 USM L - by Klaus - 07-12-2015, 09:29 AM
Canon EF 11-24mm f/4 USM L - by davidmanze - 07-12-2015, 12:05 PM
Canon EF 11-24mm f/4 USM L - by Rover - 07-12-2015, 01:37 PM
Canon EF 11-24mm f/4 USM L - by soLong - 07-12-2015, 05:04 PM
Canon EF 11-24mm f/4 USM L - by soLong - 07-14-2015, 05:44 AM
Canon EF 11-24mm f/4 USM L - by Klaus - 07-14-2015, 11:46 AM
Canon EF 11-24mm f/4 USM L - by Scythels - 07-14-2015, 01:21 PM
Canon EF 11-24mm f/4 USM L - by borisbg - 07-14-2015, 06:53 PM
Canon EF 11-24mm f/4 USM L - by soLong - 07-14-2015, 07:36 PM
Canon EF 11-24mm f/4 USM L - by borisbg - 07-15-2015, 02:01 AM
Canon EF 11-24mm f/4 USM L - by JJ_SO - 07-15-2015, 05:57 AM
Canon EF 11-24mm f/4 USM L - by Klaus - 07-15-2015, 06:33 AM
Canon EF 11-24mm f/4 USM L - by JJ_SO - 07-15-2015, 06:59 AM
Canon EF 11-24mm f/4 USM L - by Klaus - 07-15-2015, 09:53 AM
Canon EF 11-24mm f/4 USM L - by Scythels - 07-15-2015, 12:28 PM
Canon EF 11-24mm f/4 USM L - by soLong - 07-15-2015, 09:59 PM
Canon EF 11-24mm f/4 USM L - by Klaus - 07-16-2015, 11:28 AM

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