Gunzorro
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Part of my interest in trying my friend's lenses was to come to a conclusion as to the condition of his newly purchased (a few months back) of the renowned FE 24-70/2.8 GM lens. We'd both been experiencing unexpected OOF, front-focus, and even blurry focus on shots we both thought should have been simple and normal procedure.
So I started my day as a "donation" to try and find out what was going on -- was it "us" or was it the lens.
Naturally, like most honest adventurers, we looked to ourselves as the potential culprits for camera settings or technique. So I mounted the lens on my up-to-date firmware a7R2 (updated at least to cover the 24-70 introduction) and proceeded.
Out of my first 52 images taken, mostly zoomed from extremes for each subject, 24mm and 70mm, I had 12 obvious "misses", and by that I mean they were disastrous misses that shouldn't be shown on a discussion board, and certainly would never be presented to a client or published. That's 25% fail rate. As a point of reference: for this sort of mixed distance scenery shooting with my humble Canon 24-105/4L IS original version, I have less than 5% that the camera has misfocused (really it is near zero, probably my occasionally rushed technique is the true reason some shots are off) -- I mean, I can shoot that lens through the windshield of a moving vehicle and get sharp shots!  Also -- I always shoot with precise one-shot center point AF.
Anyhow, I shoot how I shoot, some are better or more precise, some are looser and blurrier! But I count myself as one who strives for "sharp" images and precise focus on contrasty targets.
As you can see, this first shot has absolutely nothing in focus, even though shot at 1/320. Trust me, I wasn't falling over, or having an elephant bump into me as I pressed the shutter. Nice center target, lady paused to remark to a friend behind her. No brainer, right?
Second shot is right on the money, on the red flower fonds in center.
Lastly, close, but no banana. Focus was on the flowers on the largest, darkest diagonal flower stalk in center, just where it conjoins the others behind it. If you look critically at the flowers on the far left and the flowers just below center to the right, you'll see focus is quite a bit further forward than it should be, enough to make the image loose all "pop" of what should be a high contrast image.
(PS -- I've added 100% crops of the centers of the photos in same order as the full image shots.)
This little sequence as we arrived netted only about 50%, 2 out of 4. Small sample, but keep in mind I did this for nearly 1/2 hour with a lot more samples. What a relief with I put my Loxia's on and could control focus. It's pretty sad when a nice used copy of a cheap Canon L zoom, beats the pants off the high-end GM! (We'd had previous outing a while back that gave rise to our suspicions.) (PS -- I will admit, the shots look better here at the 1600 setting, but at 100% viewing, they start to fall apart -- maybe I'm too picky?)
This went on through about 100 shots, with just as high a percentage of unexpected disappointments. The shots that DID focus properly were awesome! Very nice imaging when it's "on". Perhaps this is simply a lens in need of firmware upgrade, because using Steady Shot, it does seem to "meander" and loft around in the viewfinder before settling down. Or perhaps it's a lemon. My advice was to take it back to the fancy brick-and-mortar Samy's camera where he bought it (along with all his Sony gear) and explain to them and have them send it to Sony under warranty.
Half of equipment buying is the testing procedure we must all undertake to ensure the gear lives up to its requirements. The faster we do that, the faster we get proper functioning gear! I just take it in stride and don't get emotionally attached until it proves out.
This not a gripe or a slam on Sony or GM (or we photographers) simply sharing the technical challenges we all encounter and need to solve in a timely fashion.
Cheers!
Nobody wants to see this turn up in review of images, right? :)
This one is fine, crisp in the subject area in exact center flowers.
And this one is fine too at 24mm after the lady had passed by.
Almost, but no donut!
WTF? :D Not acceptable.
Good!
Good!
Front focused on lower right, not dark stalk just left of center (to show where the focus shifted forward)
Edited on May 05, 2017 at 10:32 AM · View previous versions
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I'll be down to "likes" and remarks for the coming period. Perhaps this will be the trip when I establish high speed internet at my house there, instead of relying on 4G phone service. 
