Question about Canon 50mm 1.4 AF and AFMA

[Dave_NYC]

I am trying out a Canon 50mm 1.4 after having substantial problems with a shifting depth of field on a Sigma 50mm (which I loved in every other respect, it was definitely sharper than this canon in the 1.4 - 2.0 range.).

Trouble is, I'm seeing something with the Canon as well. Basically, if I am within about 8 feet from the focus subject, I get relatively good AF accuracy (allowing for some fluctuation). But the second I hit 10 feet or so, I have to push AFMA to -10 or pretty much every shot is OOF.

Is this to be expected, or did I just get a bum copy? Would appreciate any input here, my return window is closing next week, if I need to get it exchanged or outright returned.

 

[Sporgon]

There seem to be hundreds of EF 50 f1.4 out there that are actually broken inside - mine included. They still work - in a fashion. There is some plastic part involved in the focus which is ludicrously fragile.

If you have picked yours up used this could be the problem. If it's new, I doubt it.

 

[Random Orbits]

If the problems persist at f/2.8 or smaller, exchange it. The copy I evaluated was soft wide open to about f/2.8. After that, it was sharp.

 

[Mt Spokane Photography]

Return both. Its normal for Sigma to have AF issues, but something sounds damaged on the Canon lens.