24-70mm CA issue

[Benjamin]

I see these type of CA all the time with my 24-70L. I'm very sure that you're not along with this and it's not an issue of the lens. I also see the same type of CA on the Sigma 50/1.4 and my 85/1.8 lenses. I'm not sure about the theory behind it, If you see Bryan's review about the 85/1.2L II going through a focus calibration on the 1Ds III body here (go down the page until you find the section), the same type of CA occurs when the lens is not well in focus. I assume this is just an optical property, nothing serious to worry about.


As long as the CA does not appear at the point where the image is sharp on focus, I personally don't really care.

[Colin]

Interesting.


It may be, then, that the Chromatic Abberation issues arise moving out of focus. I noticed that in the focal plane, in the middle of the screw, there isn't any to speak of. If that's just the way it is, it is, and it's up to post-processing and stopping down to deal with it.

[Colin]

So, the saga continues...


At this point, the question is, "Is the 24-105 lens actually superior to the 24-70 when it comes to chromatic aberration beyond the focal plane, or did I (and a few others) just get bad copies of the 24-70?"





Now, I realize that this isn't an exact duplicate, as the natural lighting changed a little and I didn't hold the paperclip exactly the same, but I think the results are still valid, particularly since I tried this several times and got similar results on each...





Both at f/4, both at 70mm focal length.


I'm wondering if Canon is going to give me an excuse, admit to the particular design shortcoming of the 24-70, or actually step up and fix the damn thing.