Choderboy wrote in post #18632480
OK, I will be the one to ask: Is your lens a 24-70 f4 L IS? The reason for asking is you have 'mkii' in your title but there is only a first version of this lens.
The 24-105 F4 L IS has a MKII and both versions have IS.
Yeah, I was going to ask too.
It's EITHER a 24-70mm f/4L IS USM... OR a 24-70mm f/2.8L USM II (no IS).
Since original poster noted turning IS on, I'm going to assume it's the former (i.e., it's not a "II", since none exists).
First question: Do you have a "protection" filter on it? If so, try without any filter.
Next question: Have you set Micro Focus Adjustment with the lens on your particular camera? If no, that might be worth a try.
Next set of related questions: What are you comparing it to... what other lenses do you use... and how do you use it... what do you shoot? The reason I ask these is to gauge your expectations and whether or not the lens is a "good fit" for you. For example, I've mostly seen comments that this particular lens is weakest at 50mm setting, which is something I rarely use on my full frame camera, so that wouldn't bother me. I also know it has some "focus breathing" at closer distances... but it also has an unusually high magnification "Macro" setting (0.70X, which is triple that of most zooms around this range), which is quite good and would mean I could leave my macro lens at home most days.
Final question: Have you tried it with the IS turned off? That "locks"a group of elements in place that are normally allowed to move to counteract camera shake.
Most reviews give the lens high marks, And their tests and sample images done with it seem to support their conclusions. See:
But not everyone is enamored with it and one reviewer had to exchange it for other copies a couple times to get what they felt was a "good copy". See:
One of those reviewers compares it not too favorably to the older, original 24-105L... which I've been unimpressed with (and didn't get improved much in terms of image quality with the "II" version... mostly got better IS and, maybe, built/durability).
Overall... The 24-70mm f/4 IS USM is not a match for the 2X as expensive 24-70mm f/2.8L "II", which many consider to be one of the best lenses in this range ever made. But at the price, I'd say it's pretty darned good.
We also don't know your level of experience, skill and technique... any of which might be a factor.
Yes, it could be a "soft copy". That happens, though it's relatively rare. Especially with L-series lenses. But, if you can believe the reviews, apparently may be more common with this lens than with some others.
Try to eliminate other possibilities and if the lens still doesn't "wow" you, try exchanging it to see if another copy is better, or trade it toward and some additional money toward one of the even higher end models.