Does Canon have quality control?

When I had APS-C bodies, I found the 17-40 to be the perfect walking around lens...

Thanks SVT. I plan on doing more landscapes this summer and if the 24-105 isnt wide enough im going to get something wider.

SVTmaniac wrote in post #14289876
I actually sold my 17-55 for the 17-40. Just can't live without the L

Some will question whether or not you'll need a psychiatric evaluation with comments like that ...

In regards to the two MA pics, I wouldn't put much value on your results.

I can't tell for sure, but that rope looks like it is a bit elevated with respect to the plane of your camera/lens. Consequently, you really don't know where on the rope the camera chose to focus. Also, the bottom half of the rope looks to be behind the top half due to the knot. I think there are just way too many variables to say it's off by +9

FWIW, I've placed my camera on a deck rail and focused on a rock that I placed on the rail...after 41 pictures, without ever moving the camera, my images were sharp at -6, +2, and +14. You really need to use a controlled, "proven" setup for accurate results. Doing this, I settled on +3 and have been happy with sharpness ever since.

mannetti21 wrote in post #14290518
In regards to the two MA pics, I wouldn't put much value on your results.

I can't tell for sure, but that rope looks like it is a bit elevated with respect to the plane of your camera/lens. Consequently, you really don't know where on the rope the camera chose to focus. Also, the bottom half of the rope looks to be behind the top half due to the knot. I think there are just way too many variables to say it's off by +9

FWIW, I've placed my camera on a deck rail and focused on a rock that I placed on the rail...after 41 pictures, without ever moving the camera, my images were sharp at -6, +2, and +14. You really need to use a controlled, "proven" setup for accurate results. Doing this, I settled on +3 and have been happy with sharpness ever since.

That was after I did a big MA test and found +9, that was just a test shot when all was said and done. Then I set the MA back to 0 to compare.

peregrineflier wrote in post #14289408
I bought a new Canon 300mm f4 IS and was very unhappy with the images taken with my 1D mk3. Had been wanting a 7D so I bought one, and the images were no better.
So, I did some MA on the 1D, took +8 to get it sharp. Today I did the 7D, and this is the differance between 0 and +9.
Should not have to MA a new lens that much, IMO
MA at 0

Purely picking on this point, to my knowledge a lens does not drift over time, ie. new lens "should be MA 0" then five years on you will need MA +5.

I don't think it works like that therefore either a lens needs MA or does not.

So if all new lenses should have a MA of 0 canon would have to deal with impossibly tight tolerances.

i bought my 300 from the canon refurb store, it was perfect out of the box.

I think some people need to do a little reading on the subject of Micro Focus Adjustment - like this.