03-24-2012, 03:13 PM
[quote name='Klaus' timestamp='1332591090' post='16977']
Not as bad as expected:
[url="http://www.opticallimits.com/canon_eos_ff/726-canon28f18eos5d"]http://www.opticallimits.com/canon_eos_ff/726-canon28f18eos5d[/url]
[/quote]
your test mirrors my real life observations. Resolution drops off midframe and than recovers towards the corners and borders. corner performance being a tiny bit better than border performance.
one thing id like to add though. AF precision is virtually none existant. it is almost impossible to get an in-focus shot at f1.8 -f2.5. no amount of af-micro-adjustment helps as focus is not consistently off in one direction. before somebody calls bad techbique: i always get spot on focus with the 85mm 1.8, so it definately is a lens issue.
Not as bad as expected:
[url="http://www.opticallimits.com/canon_eos_ff/726-canon28f18eos5d"]http://www.opticallimits.com/canon_eos_ff/726-canon28f18eos5d[/url]
[/quote]
your test mirrors my real life observations. Resolution drops off midframe and than recovers towards the corners and borders. corner performance being a tiny bit better than border performance.
one thing id like to add though. AF precision is virtually none existant. it is almost impossible to get an in-focus shot at f1.8 -f2.5. no amount of af-micro-adjustment helps as focus is not consistently off in one direction. before somebody calls bad techbique: i always get spot on focus with the 85mm 1.8, so it definately is a lens issue.