AFMA'ed the 24-70 mk.ii ... not sure I am loving this copy.

[Mt Spokane Photography]

So contrast AF is more accurate than phase AF ?

Yes, but slower.  Phase detect uses a separate sensor, and if that sensor or the optics in front of it are misaligned relative to the image sensor, focus will be off (and that why there's AFMA - to correct that misalignment).  Contrast detect uses the image sensor itself to determine focus - nothing to misalign.

+1
Contrast detect is not perfect, but so close that it doesn't matter.  Its just slow.  You can also chose the area you want to focus on by moving the white rectangle with your joystick (if there is one).
It is a good way to check your phase detect AF, if live AF is sharp and phase detect is not, you need a adjustment.  If neither are sharp, the issue might be more serious than a simple adjustment.

[K-amps]

Thanks John and Mt and everyone else.  Conducting tests now.... will report back.

[K-amps]

First the good news... I get about the same values for last focal test 0 and 5 (W and T).

Attached are 3 shots labelled as Phase/Contrast/MF respectively. Shows Phase/ contrast very close (all 100% crops) and the MF a bit sharper.

[K-amps]

I think I am fine with center sharpness... however the corners are a bit worrisome... especially at 24 mm... this is supposedly the best 24mm canon has at corners... should I be concerned? I know I shot the "wall" but it is straight and plane 

I am attaching resized (to fit CR) non cropped frames of both 70mm and 24mm... let me know your thoughts.

(I know there is vignetting and noise in the corners... but it is lack of resolution that concerns me)

[wickidwombat]

it looks to me that you have significantly more vignetting in the left side of the frame from that on the right
could be your lens is decentered, I would take it back to the store and try another copy take those images with too to show them.

strange thing is this new version was supposed to fix decentering issues with the 24-70 that were common with the mk1

[K-amps]

it looks to me that you have significantly more vignetting in the left side of the frame from that on the right
could be your lens is decentered, I would take it back to the store and try another copy take those images with too to show them.

strange thing is this new version was supposed to fix decentering issues with the 24-70 that were common with the mk1

That could be my lighting set up... Let me try another shot with diffused daylight....

[K-amps]

2 more shots wide open at 24mm taken outdoors. Lighting should be even. One of the wall, the other of the concrete floor.

thoughts?

[wickidwombat]

left side vignetting still looks heavier to me, darker and intrudes into the image more than on the right side

[Dylan777]

left side vignetting still looks heavier to me, darker and intrudes into the image more than on the right side

+1....left side does seem to be heavier.

[K-amps]

Ok so we established that the left side is heavier.... what now, should we consider the resolution at the corners as well or is this a return/ exchange contender?   

[Dylan777]

Ok so we established that the left side is heavier.... what now, should we consider the resolution at the corners as well or is this a return/ exchange contender?   

K-amps, I have similar problem. I'm going to return mine and exchange for another one

[K-amps]

Ok so we established that the left side is heavier.... what now, should we consider the resolution at the corners as well or is this a return/ exchange contender?   

K-amps, I have similar problem. I'm going to return mine and exchange for another one

I was just watching a few episodes of the Jamie Kennedy Xperiment and switched to CR & saw your post Dylan... Are you for real?? 

[neuroanatomist]

Assuming you've ruled out a mis-mounted lens hood, I'd say it's decentered and I'd exchange it.

[Mt Spokane Photography]

Assuming you've ruled out a mis-mounted lens hood, I'd say it's decentered and I'd exchange it.

Yes, I'd go for a replacement, except that I'm just sitting back and seeing how everyone is doing with theirs.  So far, I've read about a lot of sample variation, which is a bit disgusting.  I'd consider the Tamron, except it seems to have even more issues with QC.
Once you have found a good one, never let it go.

[wickidwombat]

Ok so we established that the left side is heavier.... what now, should we consider the resolution at the corners as well or is this a return/ exchange contender?   

at that price i would be taking it back to compare with another copy for sure